In the news: Two Small Diet Changes Pack Potentially Big Health Impacts

Beans & Tomatoes For a Healthy New Year

Two recently published studies suggest that making a few simple dietary changes can support health in meaningful ways. One study looks at the impact of beans on the intestinal tract, while the other reports that tomatoes may favorably influence blood pressure.

Beans Benefit the Gut in Multiple Ways

Beans, lentils and chickpeas are good sources of prebiotics, which are undigestible carbohydrates that serve as food to fuel and grow healthy bacteria.

Investigators studied participants in the BE GONE trial to see what effects beans might have on gut and metabolic health in high risk, overweight patients – in this case patients with a history of colorectal cancer or polyps. The BE GONE trial stands for ‘Beans to Enrich the Gut microbiome vs. Obesity’s Negative Effects’, and was conducted by the MD Anderson Cancer Center(1).

After a run in period where participants followed their usual diet, they were then randomly assigned to stay on their usual diet without beans or to continue their normal diet while adding 1 cup of canned organic navy beans daily for a month. At end of 4 weeks the groups crossed over to the other intervention.

The addition of the beans led to increased counts of friendly bacteria, mostly Bifidobacterium, as well as increased levels of the beneficial metabolites they produce.

Importantly, favorable changes in immune and inflammatory markers were also seen during the bean consumption period – biomarkers associatied with metabolic obesity and colorectal cancer.

Notably, the effect of returning to the usual diet without beans was quite stricking according to the study authors. The favorable changes in bacteria and metabolites was reversed within 4 weeks.

Including beans to the diet as frequently as possible appears to be a simple and straightforward way to promote gastrointestinal tract health.

Tomatoes: A Healthy Blood Pressure Food

The PREDIMED trial is a large study(2) designed to assess the effects of the Mediterranean diet on the prevention of cardiovascular disease.

Researchers recently anlyzed information from over 7,000 PREDIMED participants to investigate the potential effects of tomato intake on blood pressure. Tomatoes are a good source of potassium, vitamin C and especially the antioxidant lycopene.

Participants were grouped into four categories representing highest, upper intermediate, intermediate and lowest tomato intakes. The groups were then followed for a 3-year period.

Comparing highest to lowest intake groups at the end of the study period showed that those who eat the most tomatoes were 36% less likely to experience hypertension.

The lowest intake was less than 44 grams of tomato daily or about 1 ½ ounces, while the highest intake was at least 110 g (approx.. 4 oz).

The study authors suggest aiming for a large sized tomato daily, and recommend consuming tomato products as well. They also speculate that lycopene may be driving the study results through it’s ability to quench free radicals as well as to inhibit an enzyme (ACE) that has a direct effect on blood pressure.

Along with physical activity, eating well, and maintaining a healthy weight, tomatoes may be one additional way to help tame high blood pressure – important because hypertension is a big contributor to stroke, heart attack and renal disease.

References

1. Zhang X, et al. Modulating a prebiotic food source influences inflammation and immune-regulating gut microbes and metabolites: insights from the BE GONE trial. eBioMedicine Vol. 99, Dec. 2023.
2. Mercia Les-Mes, et al. Association between tomato consumption and blood pressure in an older population at high cardiovascular risk: observational analysis of PREDIMED trial. Eur J Prev Cardiol. Nov. 2023.

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In the news: Healthier Pasta & Rice; Nutrients Linked to Brain Health

Strategy for Making Rice and Pasta Healthier

Many people with pre-diabetes and type 2 diabetes avoid eating starchy foods like potatoes, white rice and pasta because they’re concerned that these foods might trigger spikes in their blood sugar.

Others turn to brown rice and brown pasta because they contain more fiber than the “white” version of rice and pasta – about double the amount of fiber for wheat pasta, and 1 to 3 grams more for brown vs. white rice.

Not only does the extra fiber help avoid large, rapid increases in blood sugar, but a higher fiber diet in general promotes a healthy gut.

Fiber, for example, serves as fuel for the beneficial microbes that inhabit the gut. Friendly microbes, in turn, produce molecules that are associated with lower inflammation and healthier cholesterol metabolism.

Now, scientists have discovered that there’s a way to make white starchy foods much healthier. The process simply entails cooking and cooling the food.

This method increases the fiber content by changing the starch into ‘resistant’ starch wihch is more resistant to digestion and absorption. The cooking and cooling method has been shown to up the amount of resistant starch in rice, pasta (noodles) potatoes and lentils.

Fiber has been linked to a lower risk of many health problems incuding type 2 diabetes, heart disease, and cancer. Resistant starch, in particular, has been found to reduce the risk of certain genetically linked types of cancer.

A study(1) carried out by reserchers in the UK tested the effects of cooking, cooling and reheating pasta on blood glucose. They found that with both cooled and reheated pasta, blood glucose levels returned to fasting levels more quickly than when eating freshly cooked hot pasta.

The results indicate that reheating pasta that’s already been cooked and cooled likely retains it’s resistant starch content. So while this adds a step or two to preparing these starchy foods, it adds to their health benefits and may be useful in helping to manage blood sugar levels as well.

Nutrients & Brain Health in AREDS 1&2

A number of studies have found that eating a certain way or consuming certain nutrients support brain function as we grow older. These studies include those that look at participants in the first and second age-related eye disease studies (AREDS 1 and 2).

A study published in 2020, for example, reported that participants in AREDS 1 and 2 who followed the Mediterranean (Med) diet pattern most closely had a significantly lower risk of cognitive impairment. Fish intake was also linked with higher cognitive function.

The AREDS research group recently published a study analyzing associations between nutrients and altered function or decline(2) . They identified some nutrients linked with lower risk of cognitive impairment or higher cognitive function scores.

Nutrients with the strongest and most consistent favorable associations included: Vitamins A, C, E and several B-vitamins. The minerals copper, magnesium, selenium, and zinc. The carotenoids lutein, zeaxanthin, beta-carotene and lycopene, as well as the lipids DHA, EPA, and fiber.

Some nutrients with potentially harmful associations included certain fats such as saturated fatty acids, and diets with a high glycemic index or load – diets with high glycemic index foods that cause a rapid increase in blood glucose.

References

1. Hodges C, et al. Method of food preparation influence blood glucose response to a high-carbohydrate meal: A randomized cross-over trial. Foods 9:23, 2020.
2. Keenan TDL, et al. Dietary nutrient intake and cognitive function in the Age-Related Eye Disease Studies 1 and 2. Alz Dement. 19:4311-24, Oct.,2023.

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In the news: Ocular Blood Flow and Glaucoma; Evidence-Based CAM Strategies

Lower Ocular Blood Flow May Help Predict Glaucoma Progression

The cornerstone of treatment for people with open-angle Glaucoma is maintaining a lower fluid pressure inside the eye, called intra-ocular pressure (IOP). It’s important because untreated high IOP can damage the optic nerve.

However, while lowering elevated IOP is crucial, it has been found that glaucoma can progress in some patients despite having well-controlled IOP. One factor that may contribute to this progression is impaired ocular blood flow. Ocular blood flow functions to bring needed oxygen and nutrients to the eye.

What has been missing, however, are long-term studies looking at whether ocular blood flow (reflected by bio- markers) may actually predict progression of the disease. In a recently published study(1) a team of US and Italian researchers provide more insight into the predictive value of blood flow in the eye.

The researchers evaluated 112 patients with early to moderate glaucoma at the beginning of the study and every 6 months over a 5-year period. They looked at capillary blood as well as functional and structural changes to the eye.

The results showed that lower retinal capillary blood flow in the superior retina (the top portion of the retina) was significantly linked to structural progression in glaucoma such as thinning of the retinal nerve fiber layer.

Research is continuing in hopes of better understanding how to protect the optic nerve and retinal cells from the effects of poor ocular blood flow and other potentially damaging factors such as oxidative stress.

Support for Some ‘Natural Pharmacy” Ingredients & Strategies

News that the US Food and Drug Administration declared that Phenylephrine – a common ingredient in over-the-counter cold, allergy and hay fever medications – is no better than placebo at relieving congestion, has prompted a new look at potential alternatives.

Some natural ingredients have proven to be effective remedies over the years. Honey, for example. There is increasing evidence that a single dose of honey might reduce mucus secretion and reduce cough in children.

While the evidence isn’t always from long and large clinical trials, when it comes to relieving congestion several ingredients or strategies come to mind that might be worth a try. Keep in mind that it’s always a good idea to run any new supplement or regimen by your physician to make sure it is right for you.

If congestion is due to hay fever, two herbal possibilities arise. One is butterbur leaf extract, which small studies suggest may be helpful in allergic rhinitis (hay fever) at doses standardized to 8 mg petasin – usually 50-150 mg of extract daily. One word of caution: Since butterbur contains toxic pyrrolizidine alkaloids (PA), be sure that the herbal product is labeled PA-free.

Results of a 2016 trial(2) indicate that turmeric, a common Asian spice containing curcumin, might be another botanical of interest for those with hay fever. That 2-month long study reported that 500 mg turmeric daily reduced nasal symptoms including congestion and improved air flow in those with allergic rhinitis.

Finally, for congestion due to both allergy and cold or flu, nasal Irrigation can be an effective strategy. It can flush out mucous and allergens, and for those who fight sinus infections, it may calm symptoms and reduce antibiotic use. The cautionary note here is use distilled or sterile water, or water that’s been boiled 3-5 minutes and cooled.

References

1. Vercellin AC Harris A, et al. Ocular blood flow bio-Markers may predict long-term glaucoma progression. BJO [Epub ahead of print] Oct, 18, 2023.
2. Wu S, et al. Effect of curcumin on nasal symptoms and airflow in patients with perennial allergic rhinitis. Ann Allergy Asthma Immunol. 117:697-702, 2016.

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In the news: Exercise to Keep Blood Pressure in Check; Vitamin D May Help Protect Colon Health

Isometric Exercises May Lower Blood Pressure

Regular exercise is one of the pillars of preventing and treating hypertension, along with weight reduction, eating the DASH diet, reducing sodium, and lowering stress. Current recommendations call for at least a half an hour of aerobic exercise most days of the week.

While many forms of exercise can be beneficial for high blood pressure, is there a particular mode of exercise that might be optimal for reducing high blood pressure? Since hypertension affects nearly half of Americans and can lead to serious health problems (heart attack, stroke), research into exercise modes continues.

In the current study(1), UK researchers analyzed data from 270 randomized controlled trials that included more than 15,800 people assigned to different types of exercise. The trials included aerobic exercise training (AET), resistance training (RT), combined training (CT), high-intensity interval training (HIIT) and isometric exercise training (IET).

While the researchers found that all modes of exercises were effective at reducing both systolic and diastolic blood pressure, the isometric (IET) was the best – and by a considerable amount for systolic blood pressure.

IET showed reductions (in mm Hg) of 8.24/4 for resting systolic pressure compared with 4.49/2.253 for aerobic, 4.55/3.04 for resistance, 6.04/2.54 for combined, and 4.08/2.50 for high-intensity interval training.

All the types of exercise studied significantly reduced systolic pressure in normal blood pressure groups, while reductions were larger in those with hypertension.

If you have high blood pressure, it’s always a good idea to check with your own physician to decide the form of exercise that’s best for you.

Isometric exercise involves increasing tension in a muscle without moving any surrounding joints. Wall squats, for example, involve slowly moving into a squat as the back is pushed against a wall, the position held, then coming back up. Examples of other isometric exercises include planks, calf raises and glute bridges.

Can Maintaining Adequate Vitamin D Blood Levels Lower Colorectal Cancer Risk?

The past several decades has seen a drop in the death rate from colorectal cancer among older Americans, most likely due to better detection (regular colonoscopies) and lower rates of smoking. However, the rate of this cancer has been increasing among those younger than 50.

Why this rate is rising isn’t understood, but many factors have been linked with higher risk of colorectal cancer including lack of exercise, being overweight, eating a low-fiber, high-fat diet, consuming processed meats, and other factors.

Results from a new study(2) suggest that vitamin D may be a contributing factor in colorectal cancer prevention, possibly through its ability to help regulate gene expression.

Researchers followed a little over 236,000 people for whom they had blood levels of vitamin D, for about 6 ½ years. They compared blood levels of those who developed colorectal cancer with those who did not.

The risk of colorectal cancer was higher among younger individuals 50 and under who had lower blood level of vitamin D (less than 20 ng/mL).

Those with vitamin D levels above 20 ng/mL had a reduced risk of developing this cancer, and the risk continued to drop with greater vitamin D blood levels. For people older than 50, the association of vitamin D and risk for of developing colorectal cancer were like those seen in younger participants, but not as pronounced.

The results do not prove that vitamin D may help prevent this cancer, but they do set the stage for further studies.

References

1. Edwards J, et al. Exercise training and resting blood pressure: a large-scale pairwise and network meta-analysis of randomized controlled trials. Br J Sports Med, Epub July, 2023.
2. Kim Y, et al. Serum 25-hydroxyvitamin D levels and risk of colorectal cancer: an age-stratified analysis, Gastro-enterol. 165: 920-931, 2023.

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In the news: Relaxation Helps Lower Eye Pressure; Daily Multi Slows Memory Decline

Relaxation techniques Help Lower IOP in Glaucoma

Eye pressure – also called intraocular pressure or IOP – is a measurement of the fluid pressure inside the eye. A higher IOP is a feature of many of the most common types of glaucoma, and lowering elevated IOP is an important treatment goal.

A newly published systematic review(1) reports that various relaxation techniques may help reduce IOP – findings that suggest these techniques may be beneficial along with standard medical treatment for glaucoma patients.

Previous trials had looked at the effect on IOP of various relaxation methods including mindful meditation, ocular relaxation exercises, yoga ocular exercises and autogenic relaxation, a self-relaxation technique that involves silently repeating one or more statements intended to produce relaxation and emotional calm.

In analyzing the trials, the researchers found that mindfulness meditation consistently resulted in long-term reductions in IOP. About a 32% decrease in IOP was seen at 3 weeks after participating in mindful meditation in the best trial evaluating that relaxation method.

Autogenic relaxation exercises showed a trend toward reducing IOP in the short term and a significant reduction in the long-term.

Ocular relaxation exercises combined with visualizing aqueous humour drainage showed both rapid and long-term reductions in IOP. (The continuous production of the eye’s fluid, called the aqueous humor, and its drainage helps maintain normal IOP). Both the autogenic relaxation and the ocular relaxation exercises were associated with about a 15% IOP reduction at 16 weeks

Yoga ocular exercises were associated with long-term reductions in IOP – about a 22% lower IOP at 6 weeks. Note, however, that the effects of yoga on IOP seem to depend on the positions being practiced. Yoga exercises with a head-down position may cause an increase in IOP.

If you are interested in trying any of these techniques, it’s best to talk with your eye care professional to see what method might be best for you, and whether resources for learning / practicing these techniques are available in your area.

Mindful meditation programs are increasingly offered at colleges, in various medical settings, and online, making this technique relatively easy to find.

Daily Multi Again Shows Slower Cognitive Aging

The COSMOS-Mind trial (“Cocoa Supplement and Multivitamin Outcomes Study”) is a large study designed to look at the effects of cocoa flavonoids and a multi-vitamin and mineral supplement (multi) on cognitive health. It’s a collaboration of Harvard Medical School and Wake Forest researchers and is funded by the National Institute for Aging.

In 2022, the researchers reported that daily use of a multi was associated with improved memory and slower cognitive decline in older individuals compared to those assigned to placebo(2). The multi group had a 60% slowing of global cognitive aging vs. placebo.

Now, results from a second COSMOS study(3), this time a collaboration of Harvard and Columbia, has been published. The study included 3500 participants 60 or older and looked at performance on a web-based assessment of memory and cognition annually.

The multi group did significantly better than the placebo group on memory tests and word recall, a finding that was estimated as the equivalent of slowing age-related memory loss by about 3 years. The benefit was first seen at 1 year and was sustained across the 3 years of the study.

References

1. Zaher O, et al. Effect of various relaxation techniques on intraocular pressure in glaucoma patients: A systematic review and meta-analysis. Can J Ophthalmol. Online ahead of print, June 24, 2023.
2. Baker LD, et al. Effects of cocoa extract and a multi-vitamin on cognitive function: A randomized clinical trial. Alz Dement.19:1308-19, 2023 (1st pub Sept. 2022)
3. Yeung LK, et al. Multivitamin supplementation improves memory in older adults: A randomized clinical trial. AJCN 118:273-282, July 2023.

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In the news: MIND or MED Diets: May Keep Minds Sharper & Help Protect Vision

Best Ways of Eating for Preserving Health

As in previous years, a panel of nutritionists, dietary consultants and physicians chose the Mediterranean (Med) Diet, and DASH diet as the top diets for their overall health benefits in 2023. The Med diet won in other categories too, including Best Diets for: Healthy Eating, Plant-Based Diets, and Family-Friendly Diets.

Several new studies this month reinforce the idea that the Med and DASH diets – or a combination of the two – may be important in preserving vision and brain health as we age. First a look at the new evidence, then more information about each way of eating.

The MIND diet, Glaucoma Risk & Cognition

The newer Mind diet is a combination of the Med and the DASH diets. It incorporates many individual dietary components that have been linked to brain and ocular health, including green leafy vegetables and produce with antioxidants and flavonoids which are anti-inflammatory.

Not long ago, a study(1) found that a higher MIND diet score as shown by higher intake of foods on the MIND diet was associated with better mental functioning and slower cognitive decline in adults 65 and older, even when accounting for those with Alzheimer's disease.

A study(2) published several months ago followed the diets of participants free of Alzheimer’s who agreed to autopsies of their brains’ postmortem. The results revealed that both the MIND and Med diets were linked with less signs in brain tissues of Alzheimer’s disease.

Earlier this year, a team of researchers also reported(3) that study participants who adhered to the MIND diet had a lower risk of glaucoma – about a 20% lower risk for each 10% increase in adherence. In this study, sticking with the Med diet was not associated with glaucoma risk.

Med Diet and Age-Related Eye Diseases

Following a Med eating pattern has been linked to better odds of preserving overall health, including brain and eye health. A new paper(4) has reviewed 18 studies examining whether closely following the Med diet may influence specific age-related eye diseases. They concluded that better adherence was associated with a lower risk of age-related macular degeneration (AMD), diabetic retinopathy in type 1 and 2 diabetes, and reduced symptoms of dry eye. There was no link between the Med diet and cataracts or glaucoma (although few studies have been conducted).

Quick Look at DASH, Med & MIND Diets

DASH diet DASH stands for Dietary Approaches to Stop Hypertension. It is a healthy-eating plan designed to help prevent or treat high blood pressure. It also may help lower LDL cholesterol linked to heart disease. DASH includes fat-free or low-fat dairy products, fish, poultry, beans and nuts, while limiting foods high in salt, added sugar and saturated fat. To learn more about DASH, go to the Mayo Clinic website: https://www.mayoclinic.org/healthy-lifestyle/nutrition-and-healthy-eating/in-depth/dash-diet/art-20048456

MIND diet MIND stands for Mediterranean-DASH Intervention for Neurodegenerative Delay. As the name implies, it is partially based on the Med and DASH diets and was designed to prevent or delay the progression of dementia. Since the eye is basically an extension of the brain, the diet may be of benefit to vision as well. The diet highlights plant-based foods, recommends specific “brain healthy” foods, and limits intake of several unhealthy food items. Learn more at Harvard’s website: https://www.hsph.harvard.edu/nutritionsource/healthy-weight/diet-reviews/mind-diet/

MED diet emphasizes whole grains, fruits, and vegetables, legumes, nuts and seeds, olive oil and some lean meat and fish. Designed as a heart-healthy eating plan, it focuses on plants and includes traditional flavors and cooking methods of the region. The Mayo Clinic website offers more details: https://www.mayoclinic.org/healthy-lifestyle/nutrition-and-healthy-eating/in-depth/mediterranean-diet/art-20047801

References

1. Dhana, K, et al. MIND diet, common brain pathologies, and cognition in community-dwelling older adults. J Alzheimers Dis. 83:683-92, 2021.
2. Vergroesen J, et al. MIND diet lowers risk of open-angle glaucoma: the Rotterdam Study. Eur J Nutr. 62: 477–87, 2023.
3. Agarwal P, et al. Association of Mediterranean-DASH Intervention for Neurodegenerative Delay and Mediterranean diets with Alzheimer disease pathology. Neurol. 100 (22), 2023.
4. Yi Wu, et al. The Mediterranean diet and age-related eye diseases: A systematic review. Nutrients 15:2043, 2023.

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In the news: New Findings for Flavonoid-Rich Blueberries: Gut & Bone Health

Blueberries May Play a Role in GI Health

Blueberries are a great source of fiber and polyphenols (e.g., flavonoids like anthocyanins) best known for their ability to reduce the risk type 2 diabetes, heart disease and mental decline associated with aging.

Aside from these benefits, a new study(1) conducted by a Swiss and Danish research team suggests that these berries can help with symptoms of functional gastro-intestinal disorders (FGIDs) too. FGIDs are also known as disorders of the gut-brain interaction. The gut-brain axis links emotional and thinking centers of the brain with intestinal function.

FGIDs include conditions such as irritable bowel syndrome and functional dyspepsia characterized by symptoms of upper GI pain and/or a feeling of indigestion or mild discomfort with fullness after eating.

In the study, 43 participants with FGID consumed 30 grams of freeze-dried blueberries (equivalent to 180 grams or a little more than a cup of fresh blueberries) or a sugar and calorie-matched placebo for a 6-week period. Then, after a washout period of several weeks, the participants crossed over to the alternate treatment for another 6 weeks.

The blueberry treatment resulted in more patients reporting abdominal symptom relief compared to placebo (53% vs. 30%,). General markers of well-being and quality of life measures improved with blueberry consumption more than with placebo. Clinical scores also improved, though the improvements didn’t achieve statistical significance.

The researchers suggest that blueberries may be beneficially influencing inflammation, nerve sensitivity, and the permeability of the intestinal wall in helping with symptom relief. Additionally, the berries may be positively affecting the composition and metabolism of gut microflora. GI tract bacteria have an important role in bi-directional interactions between the gut and the brain.

Could Blueberries Bolster Bone Health?

It’s too soon to answer that question, but the results of preclinical studies suggest that blueberries are associated with improved bone health. Also, dietary flavonoid intake has been linked with better bone mineral density in population-health studies.

In a small, new study(2), researchers examined the effects of blueberry consumption on changes in bone balance. Bone is constantly broken down and rebuilt. During menopause there is a decrease in bone formation and an accelerated rate of bone breakdown caused by hormonal changes.

The investigators looked at bone calcium retention with blueberry treatment vs. no treatment in post-menopausal women. Participants were assigned to a random sequence of three 6-week interventions: a low (17.5 g/d), medium (35 g/d), or high (70 g/d) dose of freeze-dried blueberry powder equivalent to 3/4, 1½, or 3 cups daily of fresh blueberries.

Consuming the low and medium amounts of blueberries resulted in better bone calcium retention, while the high dose did not result in better bone calcium balance. The two lower doses also reduced a marker of bone breakdown.

The researchers refer to the different responses of lower vs. higher amounts of blueberries as a hormetic effect – in this case a neutral effect that has been seen in studies where blueberries were tested in animal models of menopause.

The authors suggest that eating moderate amounts of blueberries – less than a cup of the fresh berries a day – could be one strategy to help ease bone loss in healthy postmenopausal women.

References

1. Wilder-Smith CH, et al. Blueberries improve abdominal symptoms, well-being and functioning in patients with functional gastrointestinal disorders. Nutrients. 15(10), 2396, 2023.
2. Hodges JK, et al. Moderate consumption of freeze-dried blueberry powder increased net bone calcium retention compared with no treatment in healthy postmenopausal women: A randomized cross-over trial. AM J Clin Nutr. Online June 1, 2023.

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In the news: Omega-3 Levels in Blood & Risk for Diabetic Retinopathy

Diabetic Retinopathy (DR) and Omega-3 Fatty Acids

The longer a person has diabetes, the higher the chances of developing diabetic retinopathy (DR). This complication of diabetes is estimated to affect 80% of those who have had both type 1 and type 2 diabetes for 20 years or more.

The American Academy of Ophthalmology explains that high blood sugar levels cause damage to blood vessels in the retina. These vessels can swell and leak, or close and stop blood from passing through. As DR progresses, abnormal new blood vessels can grow on the retina that are fragile and prone to bleed, impacting vision.

When it comes to lowering the risk of DR, it’s essential to control blood sugar, lipids, and blood pressure. But in addition to medications, increasing physical activity and adopting a healthy diet can make a significant difference as well.

Eating more fruits and vegetables rich in flavonoids is tied to a lower risk of DR for example, and there is interest in consuming enough fish as a possible risk-lowering strategy as well.

The eye’s retina is rich in omega-3 fatty acids which have anti-inflammatory activity and may influence new vessel formation. Since inflammation is associated with the development and progression of DR, researchers have long examined whether eating omega-3 fatty acids could be related to DR risk.

One study published in 2017 for example, showed that intake of at least 500 milligrams per day of omega-3 is associated with a decreased risk of sight-threatening DR in middle-aged and older people(1). Eating 500 milligrams of omega-3 daily is achievable with two servings per week of oily fish.

Few studies, however, have looked at actual blood levels of omega-3 in the circulation and whether there’s a relationship between them and DR.

A newly published study(2) has found an association between omega-3 blood levels and a lower risk of DR and having severe DR.

Researchers from several universities and the National Eye Institute analyzed information from diabetic participants in two previous studies (the Multi-Ethnic Study of Atherosclerosis and the Genetics of Latino Diabetic Retinopathy study). The combined studies included 1,356 participants with type 2 diabetes.

The investigators found that individuals with blood levels of the omega-3 fatty acid DHA in the top 25% were 17% less likely to have retinopathy compared to the lowest 25% of DHA blood levels.

Digging deeper into the analysis revealed that people with the highest blood levels of EPA + DHA combined – or DHA alone – had 38% less severe DR compared to those with lowest blood concentrations.

According to the authors, the results of the present study suggest that maintaining ample blood levels of omega-3, particularly DHA, may be helpful in lowering the risk of developing or worsening DR.

Further studies are needed – and warranted – to see whether consuming more omega-3 is a viable approach for those with type 2 diabetes.

Both EPA and DHA fatty acids are abundant in cold water fatty fish such as salmon, anchovies, sardines, and tuna. Bluefin tuna have up to 5 times more DHA than other types of tuna, but keep in mind too, that smaller fish generally contain lower levels of mercury.

Algae and seaweed are also sources of DHA and EPA and may be an important source for those avoiding fish or eating a vegetarian or vegan diet.

References

1. Chew E. Dietary intake of Omega-3 fatty acids from fish and risk of diabetic retinopathy. JAMA. 317: 2226–2, 2017.
2. Weir NL, et al. Omega-3 fatty acids are associated with decreased presence and severity of diabetic retinopathy: A combined analysis of MESA and GOLDR cohorts. Retina. Epub ahead of print Jan, 2023.

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In the news: Vitamin D for Spring Allergies? Tai Chi and Walking for Memory Decline

Vitamin D Possibly Helpful in Spring Allergies?

Allergic rhinitis, more commonly known as hay fever, is an allergic response to specific allergens. Pollen is the most common allergen in seasonal allergic rhinitis with symptoms occurring as the seasons change.

Is there a role for vitamin in taming allergic rhinitis, and if so, who would benefit?

In an earlier study(1) in adults with allergic rhinitis who were vitamin D deficient, taking high dose vitamin D supplements for 8 weeks (along with an antihistamine) improved symptoms overall. Symptoms were less severe with vitamin D supplementation compared with those taking a placebo plus the antihistamine medication.

A more recent review(2) looking at four clinical trials conducted in children ages 5-15 years, found that taking vitamin D 800 IU or 1,000 IU daily for 1-6 months reduces symptoms of allergic rhinitis such as nasal congestion and runny nose versus children getting a placebo or no supplemental vitamin D. However, it isn’t clear whether the children participating had low levels of vitamin D to begin with.

One of the main questions regarding vitamin D is whether supplemental amounts will benefit people who already have sufficient blood levels of the vitamin. There is also debate as to what constitutes “sufficient” levels.

For example, research suggests that vitamin D may lower the risk of developing diabetes in people with prediabetes and low vitamin D. Yet vitamin D doesn’t seem to benefit those with ample vitamin D blood levels.

With some conditions, like psoriasis for instance, low vitamin D levels are common. However, it’s still not clear whether topical and/or oral vitamin D vitamin D may be helpful.

When it comes to seasonal allergies, probably the best idea is to check with your doctor and make sure you’re maintaining healthy levels of this vitamin.

Tai Chi or Walking for Memory Decline?

Evidence suggests that regular exercise seems to improve at least some measures of cognitive function in people with with age-related cognitive decline or mild cognitive impairment (MCI).

Recently Chinese researchers aimed to confirm the benefits of consistent activity in 280 plus people 60 years and older with MCI and type 2 diabetes(3). They also compared two types of supervised activities that were carried out for an hour a day, three times weekly, for five months.

People were divided into three groups: one that engaged in regular walking, and one that practiced tai chi. The third group which didn’t participate in regular activity, acted as a control. After five months, the two activity groups were encouraged to keep exercising for an additional three months.

After eight months, both exercise groups showed modest, but significant improvement in cognition compared to the control group. The greatest improvements, however, were among those who performed tai chi. Participants in the tai chi group had an average increase of 3.29 points on a cognitive assessment scale, compared to 2.32 points in the walking group, and 1.43 points in the control group.

Those in the tai chi group also had a modest reduction in fasting blood sugar levels versus the walkers and controls.

While the slow, mindful movements of tai chi seem to be a little better at improving the decline in memory and thinking that happen with MCI, the important point is to choose an activity that suits you. And stick with it.

References

1. Bakhshaee M, et al. Therapeutic effect of vitamin D supplementation on allergic rhinitis. Otorhinolaryngol 276:2797-2801, 2019.
2. Li Q, Zhou Q, Zhang G, et al. Vitamin D supplementation and allergic diseases during ch ildhood: A systematic review and meta-analysis. Nutrients 2022;14(19):3947
3. Chen Y, et al. Effects of Tai Chi Chuan on Cognitive Function in Adults 60 Years or Older With Type 2 Diabetes and Mild Cognitive Impairment in China: A Randomized Clinical Trial. JAMA Netw Open. 6(4):e237004, 2023.

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In the news: Kiwis Help Relieve Constipation; Restrict Calories to Live Longer?

Kiwi Improves GI Function & Comfort

Eating two green kiwifruits a day leads to easier bowel movements and greater abdominal comfort.

The findings, from an international multicenter controlled trial(1), could be good news for those who suffer from constipation due to irritable bowel syndrome (IBS) or functional constipation (difficult bowel movements often with no known cause). Both types of constipation are grouped under the term functional GI disorders, and are considered common and troublesome.

While several previous studies have found that regularly eating kiwifruit (Actinidia chinensis, variety deliciosa “Hayward”) may be beneficial, the studies have been small and measured different outcomes.

The current study provides convincing evidence since it is larger, includes a variety of people from New Zealand, Italy and Japan, and uses standardized tests.

Participants included healthy controls, patients with functional constipation, and patients with constipation – predominantly irritable bowel syndrome (about 60 people per group).

The patients were randomly assigned to consume 2 green kiwifruits or psyllium (7.5 g) per day for 4 weeks. That was followed by a 4-week washout (no treatment), and then the other treatment for 4 weeks. Both the kiwis and the psyllium provided close to the same amount of dietary fiber, about 6 grams daily.

Constipated participants eating kiwis experienced more easy bowel movements (called complete spontaneous bowel movements), as well as significantly improved measures of GI comfort.

Participants appeared to fare better when eating the kiwis compared to taking psyllium. Looking at the IBS and functional constipation groups combined, the effect of 2 green kiwifruits per day was significantly greater than the effect of psyllium, which is considered a first-line treatment for both types of constipation.

Can Calorie Restriction Slow Our Aging?

We’ve known for decades that restricting calories in short-lived species including worms, flies and mice can extend their lifespan. But the effects of calorie restriction in longer-living species (e.g. monkeys and humans, is more controversial).

Now, in the first-of-its-kind controlled trial(2) funded by the US National Institute of Aging, researchers from Columbia University Mailman School of Public Health report that cutting calories can slow the rate of biological aging in healthy, non-obese humans.

The trial randomized 220 healthy men and women at three research locations to a 25% calorie restriction or normal diet for two years.

Because humans live for a long time, it’s not possible to conduct a trial that could see differences in survival. So, the investigators used biomarkers to measure the pace and progress of aging over the study. The markers were developed over a 20-year period and are based on a DNA methylation blood test. Methylation marks are chemical tags on DNA that regulate genes and that change with age.

The calorie restriction slowed the pace of aging by 2-3%. While that doesn’t seem like a very big payoff for eating 25% fewer calories, other studies suggest that may translate to a 10-15% reduction in mortality risk.

A follow-up trial is now ongoing to determine if the restriction had long-term effects on healthy aging such as risk factors for chronic diseases. In the meantime, lots of questions remain. Many experts, for example, are skeptical about whether people can stick to a lower calorie diet long enough to make a meaningful difference in longevity. It’s also not yet clear whether intermittent fasting or time-restricted eating might offer similar benefits.

References

1. Gearry R, et al. Consumption of 2 green kiwifruits daily improves constipation and abdominal comfort—eesults of an international multicenter randomized controlled trial. Am J Gastroenterol. Epub Jan 9, 2023.
2. Waziry, R, et al. Effect of long-term caloric restriction on DNA methylation measures of biological aging in healthy adults from the CALERIE trial. Nat Aging. Feb 9, 2023.

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In the news: Potatoes are Part of Healthy Diet; Staving Off Fatty Liver Disease

Potatoes Have Gotten a Bad Rap

Potatoes – particularly when eaten without their skins – have gotten the bad reputation of contributing to weight gain and increasing the risk of type 2 diabetes. People with insulin resistance are often cautioned to avoid eating “spuds” as they’re called in Australia.

However, a recently published randomized trial(1), from Pennington Biomedical Research Center showed that contrary to common belief, potatoes do not negatively impact blood sugar levels. “In fact, the individuals who participated in our study lost weight”, according to the lead study author.

The results are good news since potatoes pack a lot of quality nutrition. In addition to providing a significant amount of potassium (nearly 900 mg in 1 medium-sized potato), they supply good amounts of essential nutrients like vitamins C and B6. They’re also a valuable source of fiber for those eating the skin.

The researchers evaluated the effects of low-calorie diets that were high in either potatoes or beans on blood sugar control of participants who were obese or overweight or insulin resistant, over an 8-week period.

Key Findings: Participants’ blood sugar levels were not negatively affected by consuming potatoes, the potato and bean diets were equally effective in reducing insulin resistance, and all individuals lost weight.

Study participants reported feeling fuller, and fuller more quickly, when higher-calorie items in their diet were replaced with potatoes or beans.

The researchers point out that people tend to eat the same weight of food regardless of calorie content to feel full. So, by switching to foods that are heavier in weight and low in calories (like potatoes), you reduce the number of calories consumed.

Another attribute of potatoes is that they can be prepared many ways, thus adding variety to the diet. Most people won’t stick with a diet that doesn’t offer variety. Bottom line: eating potatoes is healthy!

New Guidelines for NAFLD

New guidance published in February for primary care doctors from the American Association for the Study(2), of Liver Diseases differs from the previous guidance 5 years ago by now calling for routine screening for advanced fibrosis for people at high risk NAFLD such as those with type 2 or complicated obesity. NAFLD stands for non-alcoholic fatty liver disease.

NAFLD is a condition in which extra fat is stored in the liver but not due to excess alcohol consumption. The cause is unknown, but factors such as obesity, diabetes, or metabolic syndrome can increase the risk for NAFLD. In some, fatty liver disease can lead to nonalcoholic steatohepatitis (NASH), an aggressive form of fatty liver disease marked by inflammation. NASH may also progress to advanced liver disease.

A variety of nutrients and herbs are being researched to see if they have any favorable effect on NAFLD. Though it’s too early to draw conclusions, one of the more promising studies reports that eating one cup of probiotic yogurt daily improves markers of liver injury in people with NAFLD. It’s not clear, however, what probiotic strains or amounts may be beneficial.

Dieting is one strategy that can often prevent or reverse NAFLD, according to experts at the National Institutes of Health. People with NAFLD should limit fat intake, replace saturated and trans fats with unsaturated fats such as omega-3 fatty acids from fish, include more fruits, vegetables, and whole grains), minimize alcohol use and avoid foods and drinks containing large amounts of simple sugars.

Of the various diets tested to date, the Mediterranean eating pattern has the strongest evidence for improving markers of liver injury in people with fatty liver disease.

References

1. Rebello CJ, et al. Low-energy dense potato and bean-based diets reduce body weight and insulin resistance: a randomized feeding equivalence trial. J Med Food. 12:1155-1163, Dec, 2022.
2. Rinella ME, et al. AASLD practice guidance on the clinical assessment and management of nonalcoholic fatty liver disease. Hepatol. Epub Feb. 3, 2023.

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In the news: Fish Omega-3 Linked to Kidney Health; Vitamin D May Help in Prediabetes

Study Links Seafood Based Omega-3 with Lower Risk of Chronic Kidney Disease

A new study published in the British Medical Journal(1), found an 8-13% lower risk of chronic kidney disease and a slower decline in kidney function with a higher intake of omega-3 fatty acids from seafood sources.

Although the associations were relatively modest, the findings suggest a beneficial role of omega-3 intake in preventing and managing chronic kidney disease – a condition affecting about 700 million people worldwide, or about one in eleven people in the general global population.

This large study is important because while animal studies suggest omega 3 fatty acids have beneficial effects on kidney function, the evidence from human studies is limited.

To assess the relationship between omega-3 fatty acid intake and chronic kidney disease, a team of international researchers analyzed data from 19 studies conducted in 12 countries that included over 25,500 participants who were followed an average 11 years.

Omega-3 biomarkers indicate that these fatty acids can improve artery stiffness, lower blood pressure and reduce plasma triglycerides – all of which could help protect against the development of chronic kidney disease. The researchers found that those in the top 20% of omega-3 biomarkers had a 13% lower risk of the disease compared to those in the bottom 20% of biomarkers (which reflect intake).

Higher levels of seafood omega-3 biomarkers were not only associated with a lower risk of the disease but also a slower decline in kidney function. Seafood omega-3 included the fatty acids eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA), and docosahexaenoic acid (DHA).

On the other hand, omega-3 fatty acids from plant sources – namely alpha linolenic acid from oils such as flaxseed, canola, soy, perilla, and walnut oil – were not associated with a lower risk of kidney disease or kidney function. This highlights the need to include seafood as part of a healthy diet.

Vitamin D May Help Control Pre-Diabetes

People with prediabetes – estimated at 1 out of 3 Americans – have blood sugar levels higher than normal, but not high enough to be diagnosed as type 2 diabetes. Prediabetes, however, does raise the risk for developing type 2.

A new systemic review and meta-analysis(2), from researchers at Tufts Medical Center has found that a higher vitamin D intake by individuals with prediabetes is associated with a 15% reduced risk of going on to develop type 2 diabetes.

While previous studies have suggested a benefit of vitamin D to those with prediabetes, none of the studies were large enough to show statistical significance. Because these studies were conducted in different countries, different doses and forms of vitamin D were tested: 20,000 IU cholecalciferol weekly, 4,000 IU cholecalciferol daily, and 0.75 mcg of eldecalcitol (an analogue of D used in Japan).

Cholecalciferol reduced the risk for diabetes significantly among those who maintained a higher vitamin D blood level during follow-up. There were no apparent safety issues, with no difference in adverse events (including kidney stones, high blood or urine calcium levels) between those taking vitamin D and placebo takers.

The authors point out that there are other strategies to combat prediabetes: Intensive lifestyle modification has resulted in a 58% lower risk, and taking the drug metformin has been shown to lower risk by 31%.

References

1. Ong KL, et al. Association of omega 3 poly-unsaturated fatty acids with incident chronic kidney disease: pooled analysis of 19 cohorts. BMJ. 380:e072909, 2023.
2. Pittas AG, et al. Vitamin D and risk for type 2 diabetes in people with prediabetes. A systematic review and meta-analysis of individual participant data from 3 randomized clinical trials. Ann Intern Med. Epub Feb 7, 2023.

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In the news: For Better Aging: More Flavonols, Lutein & Zeaxanthin in 2023

Wishing a very happy new year to Staying Healthy readers from all of us at ScienceBased Health!

Flavonols May Slow Memory Slide with Age

Make it a point to eat lots of flavonol-rich foods in the new year, and the reward could be better brain function down the road.

Higher intake of total flavonols and certain types of flavonols may slow the rate of cognitive decline according to a study published in Neurology(1).

Flavonols, which have anti-inflammatory and antioxidant properties, are one type of flavonoid found in various fruits, vegetables, tea, and wine. This study focuses on flavonols as a group and on the major individual flavonols: kaempferol, quercetin, myricetin and isorhamnetin.

The study included 961 participants (60-100 years) with no signs of dementia who were followed for an average of 7 years. Cognitive performance was assessed annually with a battery of 19 standardized tests such as recalling lists of words, and remembering numbers and putting them in correct order.

An overall global cognition score summarizing the 19 tests was used to determine rates of cognitive decline. The average score ranged from 0.5 for those with no cognitive impairment to 0.2 for mild impairment to -0.5 for those with Alzheimer’s.

After adjusting for an array of other factors that could affect the results, the global cognitive score for those consuming the most total flavonols (about 15 mg a day) declined 0.4 units per decade more slowly than those who consumed the least flavonols (about 5 mg daily).

The highest intake was associated with less decline in multiple cognitive domains: episodic memory, semantic memory, perceptual speed, and working memory. For individual flavonols the highest vs. lowest intake resulted in a slower rate of cognitive decline for kaempferol, quercetin and myricetin.

The top food contributors for each category were: kale, beans, tea, spinach, and broccoli for kaempferol; tomatoes, kale, apples, and tea for quercetin; tea, wine, kale, oranges, and tomatoes for myricetin. Pears, olive oil, and wine contributed as well.

Lutein/Zeaxanthin for More than Eye Health?

According to a new study(2), greater intake of lutein and zea (zeaxanthin) may support musculoskeletal health and lower the risk for becoming frail with older age.

Due to their antioxidant and anti-inflammatory actions, these two carotenoids have been increasingly linked to conditions that involve inflammatory and oxidative stress – osteoporosis, sarcopenia, and frailty in addition to age related macular degeneration and other eye diseases.

Looking at data from over 4,500 participants in a long-term study on aging, researchers found that among those who were not frail at the study’s start, having lower plasma levels of lutein/zea increased their chances of developing frailty after 8 years.

Importantly, for every 100 nmol/L increase in plasma levels of the two carotenoids (roughly equivalent to eating two extra portions of lutein/zea daily for 4 weeks) led to a 11-20% lower risk of progressing to a higher frailty category for lutein. For zeaxanthin, the odds were 27-43% lower for that progression.

For more lutein/zea in 2023, eat dark leafy greens, eggs, corn, peas, broccoli, summer squash and red peppers. Combined with eating more flavonol-rich foods will give you a better chance of staying sturdy and mentally sharp with age.

References

1. TM Holland, et al. Association of dietary intake of flavonols with changes in global cognition and several cognitive abilities. Neurol. Epub Nov. 22, 2022.
2. Murphy CH, et al. Plasma lutein and zeaxanthin concentrations associated with musculoskeletal health and incident frailty in the Irish Longitudinal Study on Aging. Exp Gerontol. 171 (112013), 2023.

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In the news: Vitamin D Levels Important in Osteoarthritis, Meditation or Medication for Anxiety? Tip of the Month

Here’s a look at some of the more interesting nutrition and health studies published this month…

Optimal Vitamin D Levels linked to Better Life Expectancy in Osteoarthritis Patients

A new analysis(1) involving information from 4,570 patients with osteoarthritis, revealed that patients with sufficient vitamin D have a lower risk of dying from cardiovascular disease (CVD) and death from any cause.

The study examined whether blood levels of vitamin D were associated with all-cause and cause-specific mortality in participants from the National Health and Nutrition Examination Survey. The researchers focused on people with osteoarthritis because most studies have looked at the relationship of vitamin D to mortality in the general population and in diabetic patients.

After placing participants into groups based on the concentration of vitamin D in their blood, they found a lower risk of dying from CVD or from any cause (except cancer) for those with vitamin D levels equal to or greater than 75 nmol/L, with the lowest risk at levels of about 84 nmol/L. The relationship of blood vitamin D levels and mortality risk were stronger for men than women.

The authors note that the population studied had a higher proportion of people with vitamin D deficiency (about 17%) and insufficient vitamin D levels (48%) compared to similar studies which did not find a relationship between vitamin D and mortality. In vitamin D deficiency, as the authors point out, the body takes calcium from where it’s stored in bones. That weakens those bones and may play a role in shortening the lifespan.

Meditation or Medication for Anxiety?

According to a new study(2) comparing a first-choice drug treatment for anxiety to mindfulness-based stress reduction, the mindfulness meditation was just as effective (“non-inferior”) for people diagnosed with anxiety disorder.

The study included 276 individuals with an anxiety disorder, mostly generalized anxiety, or social anxiety.

One group was assigned to receive the selective serotonin reuptake inhibitor, escitalopram, which is a first-choice drug treatment for generalized anxiety.

The other group completed daily 45-minute guided meditation sessions at home.

At the end of eight weeks, both groups saw about a 30% drop in symptom scores. Fewer people dropped out of the study in the mindfulness group vs. the drug group, likely because 78% of those in the drug group experienced at least one adverse event (e.g. sleep disturbances, fatigue, headache, nausea).

The researchers point out that not everyone is willing to invest the time and effort to complete mindfulness sessions and to practice regularly at home.

However, mindfulness-based stress reduction programs are available in all major US cities, don’t require finding a therapist, and can be found in places other than a mental health environment such as yoga centers and universities. Online classes may also be available in many areas.

Nutrition Tip of the Month

You’ve heard of quercetin? It’s one of the important plant bioflavonoids that acts as an antioxidant, anti-inflammatory, and supports cellular health.

While quercetin is found in a wide variety of fruits and veggies, it is not readily absorbed. But the fiber pectin can enhance the bioavailability and blood levels of this bioflavonoid. One suggestion: Eat more apples. Not only are they a rich source of quercetin, but they are a great source of pectin as well.

References

1. Wang J, et al. Vitamin D status and risk of all-cause and cause-specific mortality in osteoarthritis patients: Results from NHANES III and NHANES 2001-2018. Nutrients. 14:4629, 2022.
2. Hoge EA, et al. Mindfulness-based stress reduction vs escitalopram for the treatment of adults with anxiety disorders a randomized clinical trial. JAMA Psychiatry. Published online November 9, 2022.

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In the news:Strategies to Prevent & Fight Gout

Making Gout-Fighting Lifestyle Changes

The last issue of Staying Healthy focused on diet and recurring kidney stones, the hard deposits made up of tiny crystals in the kidney or urinary tract. Sharp crystals that form from excessive amounts of uric acid and are deposited in the joints can cause another problem: gout.

Gout is a health problem on the rise. A study published in 2018 reports that the incidence of gout has more than doubled over the past 20 years in tandem with an upswing in obesity rates.

Gout, which is a form of inflammatory arthritis, usually starts in the big toe but can affect other joints as well, causing pain and swelling. Considered a “lifestyle disease”, there are changes in daily habits that can help minimize the frequency of flare-ups or ‘gout attacks’ for those with this condition or reduce the risk of getting gout in the first place.

Weight control is very important as excess weight can increase blood levels of uric acid and put more stress on joints. Recent findings also show that exercise may decrease pain and inflammation in gout patients.

Drinking lots of water is a must since that helps the kidneys clear uric acid, and dietary changes are in order too.

Since uric acid is a by-product of the body’s metabolism of purines naturally present in the diet, some gout suffers often must limit high purine-containing foods and beverages. These include alcohol, red meat, shellfish, gravy, drinks and foods high in fructose, and animal-source protein.

Role for Vitamin C in Gout Prevention?

There are effective treatments for gout – the drug colchicine, for example, which is used to help prevent gout attacks and treat pain during flare-ups. However, the drugs are not without the risk of side effects, and people often forgot to take medications when they’re using them regularly to prevent gout episodes. That’s why lifestyle changes like weight control and diet are so relevant to prevention and reducing gout episodes.

The results of a recent Harvard study(1) suggest that vitamin C may reduce the chances of developing gout. Since some short-term intervention trials have reported that 500 mg/d vitamin C reduces blood levels of uric acid, the researchers analyzed data from over 14,000 male participants in a large, 10-year trial that examined the effects of vitamin C in heart disease.

The researchers found that those taking vitamin C lowered their risk of getting gout. And men who weren’t overweight had the most risk reduction. While vitamin C did result in fewer new cases of gout, it did not show a reduction in gout flare-ups for participants who already had a diagnosis of gout.

Other studies have shown that vitamin C reduced uric acid levels in gout-free individuals and broke down urate crystals in blood. Emerging work also suggests that vitamin C lessens inflammation and pain caused by the immune system’s response as it tries to break down urate crystals.

What About a Vegetarian Diet?

Although some vegetables are rich in purines, researchers analyzing two large studies report that a vegetarian diet is associated with lower uric acid and lower risk of gout(2). So, going vegetarian – or at least adopting a plant-based diet – could be another strategy for staving off gout. Some even speculate that the vitamin C in fruits and veggies may reduce the effect of purines on forming uric acid.

If you have gout and are thinking about making dietary changes, it’s always a good idea to let your doctor know. Also, note that some prescription drugs can elevate blood uric acid either by decreasing uric acid secretion or by reabsorbing uric acid. Most notable are the diuretics.

References

1. Juraschek SP, et al. Effects of vitamin C supple-mentation on gout risk: results from the Physicians' Health Study II trial. Am J Clin Nutr.116:812-819, 2022.
2. Chiu T, et al. Vegetarian diet and risk of gout in two separate prospective cohort studies. Clin Nutr. 39:837-44, 2020

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In the news: Diet and Recurring Kidney Stones   

Quick Primer on Kidney Stones

Kidney stones can be small or large irregularly shaped solid masses made up of millions of tiny crystals that form in the kidney. Kidney stones form when urine contains more crystal-forming substances (e.g. calcium, oxalate, and uric acid) than the fluid in urine can dilute. Additionally, urine may be short on substances that prevent crystals from sticking together – citrate and possibly magnesium for example.

Although stones originate in the kidney, when they start to move into one of the tubes connecting the kidneys to the bladder (the ureter) they can become wedged in the tube or the opening that leads to the ureter. This causes a backup of urine and can result in considerable pain.

Of the various types of kidney stones, about 80% are calcium based (calcium oxalate, phosphate), with calcium oxalate being most common by far. Other types include uric acid, struvite (associated with urinary tract infections), and cystine. Since stone formation is specific to individuals, determining the type of stone is key to establishing a personalized treatment plan to help prevent future stones.

Kidney stones are common, with more than 1 in 10 people affected. And kidney stones can come back: the recurrence rate is about 30% at 10 years. Having a family member who had kidney stones can up the risk for developing them.

There are factors in addition to heredity that can influence kidney stone risk, and diet is one of them. Excessive sodium, animal protein and oxalate (oxalic acid bound to minerals present in some fruits and vegetables) for example, have been associated with raising the risk for stones. And one of the biggest risk factor is not getting enough fluids every day.

New Study: Better Calcium & Potassium Intake May Help Prevent Stone Recurrence

Dietary recommendations for preventing kidney stones have been based primarily on factors linked to first time stone formation rather than on recurring stone. That led Mayo Clinic researchers to design a study to look at the impact of dietary factors in recurring stone formers(1,2). The results suggest that enriching diets with foods high in calcium and potassium may help prevent recurrent, symptomatic kidney stones.

The study had two groups of participants: over 400 people who had experienced first-time symptomatic kidney stones and a control group of about 380 who had not experienced kidney stones.

Of those first-time formers, 73 went on to have recurring stones during a median 4-year follow-up. The researchers found that low dietary calcium and potassium were linked to a lower risk for recurrence. In this study, the two minerals were even better predictors of recurrence than low fluid intake.

Risk factors associated with first-time formation were low dietary calcium and potassium, low fluid intake (less than about nine 12-ounce glasses), and lower levels of caffeine and phytate (an antioxidant found in whole grains and nuts).

Not enough fluid and low caffeine intake can result in low urine volume and more concentrated urine which contributes to stone formation. Phytate is considered an inhibitor of calcium oxalate crystal formation.

The authors recommend eating more dairy for calcium and fruit and vegetables for potassium.

Fruits and veggies do contain oxalates but they’re also high in citrate which helps prevent stone formation. There are usually reasons other than dietary oxalate for forming calcium oxalate stones. But for those advised to reduce oxalate, many fruits and veggies are high potassium / low oxalate including cherries, peaches, bananas, tomatoes, cantaloupe, peas, squash and butterleaf lettuce.

References

1. Chewcharat A, et al. Dietary risk factors for incident and recurrent symptomatic kidney stones. Mayo Clin Proc. 97:1437-48, 2022.
2. Diets higher in calcium and potassium may help prevent recurrent symptomatic kidney stones, Mayo Clinic finds. Mayo Clinic News Release. July 29, 2002.

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In the news: Update on Intermittent Fasting; Fiber Fights Antibiotic Resistant Bugs

Intermittent Fasting & Weight Loss, AMD Risk

Intermittent fasting (IF) is a way of eating that involves periods of eating and fasting. The emphasis is not on what foods are consumed (hopefully healthy), but rather when they are eaten.

There are several different fasting methods. One, for example, is fasting for 24 hours once or twice weekly. Another, called the 8/16 method, involves skipping breakfast and restricting the daily eating period to 8 hours (e.g. 10-6 pm) then fasting for the next 16 hours.

The topic of IF, also called time-restricted eating, and weight control has been covered in previous Staying Healthy newsletters (see Sept. 2019 and Dec. 2016 issues at www.sbh.com). Now, a new clinical study(1)provides some evidence that time-restricted eating may help weight loss. And improve blood pressure too.

In this 14-week investigation, University of Alabama researchers focused on time-restricted eating in the earlier part of the day. The 8-hour time window for consuming food was 7:00 A.M. through 3:00 P.M. (then fasting for 16 hours) at least 6 days per week.

Ninety overweight or obese participants were randomly assigned to the 8/16 early time-restricted period group or a group that was allowed to eat over 12 hours or more. All the participants were counseled on weight loss and advised to eat fewer calories and to exercise roughly 1 ½ to 2 ½ hours per week. But both groups were on their own to follow that advice, and there were no differences between the groups in physical activity or calorie intake at the end of the study.

Both groups lost weight, but the 8/16 group dropped greater than 5 lbs. more – a meaningful amount. A closer look suggests that the 8/16 eating pattern was more effective at reducing body fat. Compared with controls, the 8/16 group also had reduced diastolic blood pressure, and greater improvements in mood, depression, vigor, and fatigue.

IF Benefits for Eye Health?

Another intriguing new study from Korean researchers suggests that IF may help reduce the risk of developing age-related macular degeneration AMD(2).

Looking at over 4,500 elderly people the researchers found that intermittent fasting by skipping breakfast was significantly associated with a lower risk of AMD (nearly 60% lower risk), especially in those less than 70 years old, people who were obese, and those living in urban rather than rural areas.

This is the first study to explore a link between IF and AMD risk. it would be important if a role for IF in AMD can be confirmed, but this is just the beginning.

Fiber May Help Fight Bad Bugs in the Gut

Whether or not you practice IF, it pays to include lots of fiber and a variety of foods in your diet according to a study by investigators at UC Davis(3).

Microbes that are resistant to commonly used antibiotics is a big problem, and one that’s only expected to grow. Antimicrobial resistance in people is largely based in their gut microbiome, where these microbes carry genetically encoded strategies to survive contact with antibiotics. The new study explored whether diet could affect the amount of antibiotic resistance microbes in people’s guts.

The researchers found that eating a diverse diet with at least 8-10 grams of soluble fiber and a lower intake of protein (especially from beef and pork) was linked to a lower level of antimicrobial resistant genes in the gut and higher levels of microbes that help dampen inflammation. But the most important predictor of low levels of antibiotic resistance microbes was eating a diverse diet of minimally processed plant foods (likely also fiber-rich). Soluble fiber is found in foods like grains, beans, nuts and some fruits and veggies.

References

1. Jamshed H, et al. Effectiveness of early time-restricted eating for weight loss, fat Loss, and cardiometabolic health in adults with obesity: A randomized clinical trial. JAMA, ePub Aug. 8, 2022.
2. Choi EY, et al. Intermittent fasting is associated with a decreased risk of age-related macular degeneration. Am J Ophthalmol. S0002-9394(22)00255. ePpub July 6, 2022.
3. US Agricultural Research Service. Diets high in fiber associated with less antibiotic resistance in gut bacteria, May 10, 2022.

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In the news: Nuts Linked to Kidney Health Polyphenols Help Gut Bacteria Thrive?

Eating Nuts Tied to Better Kidney Health

In chronic kidney disease (CKD), the kidneys become impaired over time and less able to cleanse the blood of toxic waste and extra fluid. This in turn may lead to other problems including high blood pressure, heart disease and stroke. CKD is relatively common in the U.S. with more than 1 in 7, that is 15% of adults or 37 million people, estimated to have the condition according to the Centers for Disease Control.

In recently published research(1) investigators wanted to assess whether consuming nuts might be protective against CKD, lowering the risk for developing it. Previous studies suggest that including nuts in the diet may have benefit in cardiovascular disease (CVD), obesity, cancers, and nonalcoholic fatty liver disease. Nuts may work by reducing oxidative stress and inflammation, improving blood vessels’ ability to dilate, and supporting healthy blood lipid levels.

The researchers used data from over 6,000 U.S. adults (aged 20 years or older) to evaluate the association between the consumption of nuts and the frequency of CKD in the population, as well as the mortality associated with CKD

Consuming nuts one to six times per week was linked to a lower frequency of CKD, with 33% lower odds of having CKD.

There was also an association between eating nuts one to six times weekly and lower death rate from any cause and death from CVD in people who did not have chronic kidney disease. For those with CKD, higher nut intake was also tied to lower death from any cause.

Eating nuts once to six times weekly may help lower the risk of developing CKD, though more research is needed to confirm the study’s observations.

For those who already have chronic kidney disease, it is always best to check with your physician for specific dietary advice. Diet is often a key part of managing CKD, with the purpose of slowing progression to kidney failure.

While there’s no consensus on foods that are specifically recommended, the general idea is to get adequate calories while lowering the intake of proteins, phosphorus, sodium, potassium, and organic acids. Since nuts contain phosphorus and potassium, consuming larger amounts of certain nuts may not be appropriate for everyone depending on their stage of kidney disease.

Dietary Polyphenols May Help Prevent Inflammation in Elderly Via Gut Microbiota

Researchers from the University of Barcelona have shown that a diet high in polyphenols can support micro-organisms that produce compounds important to our health. In this case, the polyphenol-rich diet raised levels of a compound called indole 3-proprionic acid or IPA.

IPA is generated by intestinal bacteria when the bacteria metabolize an amino acid (tryptophan) in foods. IPA has shown anti-inflammatory and antioxidant effects, and it helps keep the intestinal wall intact and functioning well.

In the study(2), participants over 60 years of age were randomly assigned to a high polyphenol or control diet, then switched over to the other diet over an eight-week period. The high polyphenol diet included foods rich in polyphenols like green tea, dark chocolate, and fruits such as apples, pomegranate, and blueberries.

During the high-polyphenol intake period, the participants had higher blood levels of IPA, a decrease in biomarkers of inflammation, and an increase in the diversity of bacteria associated with a healthy gut. Interestingly, the same beneficial effects were not seen in participants with kidney disease. According to the authors, this may be due to the altered composition of their microbiota compared to those with normal kidney function.

References

1. Wang K, et al. Nut consumption and effects on chronic kidney disease and mortality in the United States. Am J Nephrology. 53:503–512, 2022.
2. Peron G, et al. A polyphenol-rich diet increases the gut microbiota metabolite indole 3-propionic acid in older adults with preserved kidney function. Mol Nutr Food Res. 2100349, 2022.

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In the news: Healthy Diet for Breast Cancer Prevention, AREDS2 Formula Safer, More Effective

Diet Quality Counts for Preventing Breast Cancer

Studies have suggested that diet can influence cancer risk, but it hasn’t always been clear which eating habits or foods are best for cancer prevention.

Some research has pointed to diets with less or no meat as a risk-lowering healthy choice. A plant-based diet (as opposed to a vegan or vegetarian diet) is one that doesn’t exclude meat but focuses on plant foods over animal-based foods.

Now, the findings of a new study(1) show that not all plant-based diets are equal. The quality of those plant foods counts, with whole or unprocessed foods trumping refined foods when it comes to lowering the risk of breast cancer.

The new research concentrated on the quality of plant foods, differentiating between healthy plant-based foods such as whole grains, fruits, veggies, nuts, healthy oils, tea and coffee, and plant-derived foods classified as less health – largely processed foods including refined grains, fruit juices, potatoes, sugary drinks, and deserts

The researchers looked at data from over 65,500 postmenopausal women who were followed for more than 20 years. They compared breast cancer rates with how closely the women adhered to a mostly plant or animal diet, and whether they ate healthier vs. less healthy foods.

The study found that eating a healthy plant-based diet was linked to a 14% lower risk of breast cancer, while the “unhealthy” plant-based diet was associated with a 20% higher risk. These findings were consistently observed for all breast cancer subtypes (which are mostly defined by hormone receptors and other types of proteins).

Safety, Effectiveness of AREDS2 Supplements Confirmed at 10-Year Mark

The first Age-Related Eye Disease Study (AREDS) established that a dietary supplement can slow the progression of age-related macular degeneration (AMD).

However, the beta carotene component tested in the original AREDS study was found to up the risk of lung cancer for smokers – a risk that persisted through the second AREDS trial (AREDS2).

AREDS2 examined whether replacing beta carotene (15 mg) with lutein and zeaxanthin (10 and 2 mg), would allow the researchers to create a supplement formula that was equally effective at lowering the risk for age-related macular degeneration (AMD) and that could be used by anyone whether or not they smoke or formerly smoked.

At the end of the 5-year AREDS2, all participants were given the revised formulation with lutein/zeaxanthin, vitamins C and E, and zinc plus copper and were followed for an additional five years. The researchers wanted to know whether the increased risk of lung cancer seen in those assigned to beta carotene in AREDS continued beyond the end of AREDS2, and whether they could see any long-term benefit of adding lutein/ zeaxanthin to the AREDS2 formula.

In a new report(2), the researchers looked at 10 years of data and concluded that the revised formula with lutein and zeaxanthin not only reduces the risk of lung cancer due to beta carotene but is also more effective at reducing the risk of AMD progressing to late AMD.

The follow-up continued to show that beta carotene nearly doubled the risk of lung cancer for those who had smoked, while there was no increased lung cancer risk for those taking lutein/zeaxanthin. And after 10 years, those originally receiving these two carotenoids in AREDS2 and beyond had an additional 20% reduced risk of AMD progression vs. those assigned to beta carotene.

References

1. Shah S, et al. (OR07-03-22) Adherence to Healthy and Unhealthy Plant-Based Diets and Risk of Breast Cancer Overall and by Hormone Receptor and Histologic Subtypes Among Postmenopausal Women. Presented at the American Society for Nutrition Annual meeting, June 14, 2022
2. National Institutes of Health News Release. NIH study confirms benefit of supplements for slowing age-related macular degeneration. June 2, 2022.

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In the news: Healthy Diet for Breast Cancer Prevention, AREDS2 Formula Safer, More Effective

Diet Quality Counts for Preventing Breast Cancer

Studies have suggested that diet can influence cancer risk, but it hasn’t always been clear which eating habits or foods are best for cancer prevention.

Some research has pointed to diets with less or no meat as a risk-lowering healthy choice. A plant-based diet (as opposed to a vegan or vegetarian diet) is one that doesn’t exclude meat but focuses on plant foods over animal-based foods.

Now, the findings of a new study(1) show that not all plant-based diets are equal. The quality of those plant foods counts, with whole or unprocessed foods trumping refined foods when it comes to lowering the risk of breast cancer.

The new research concentrated on the quality of plant foods, differentiating between healthy plant-based foods such as whole grains, fruits, veggies, nuts, healthy oils, tea and coffee, and plant-derived foods classified as less health – largely processed foods including refined grains, fruit juices, potatoes, sugary drinks, and deserts

The researchers looked at data from over 65,500 postmenopausal women who were followed for more than 20 years. They compared breast cancer rates with how closely the women adhered to a mostly plant or animal diet, and whether they ate healthier vs. less healthy foods.

The study found that eating a healthy plant-based diet was linked to a 14% lower risk of breast cancer, while the “unhealthy” plant-based diet was associated with a 20% higher risk. These findings were consistently observed for all breast cancer subtypes (which are mostly defined by hormone receptors and other types of proteins).

Safety, Effectiveness of AREDS2 Supplements Confirmed at 10-Year Mark

The first Age-Related Eye Disease Study (AREDS) established that a dietary supplement can slow the progression of age-related macular degeneration (AMD).

However, the beta carotene component tested in the original AREDS study was found to up the risk of lung cancer for smokers – a risk that persisted through the second AREDS trial (AREDS2).

AREDS2 examined whether replacing beta carotene (15 mg) with lutein and zeaxanthin (10 and 2 mg), would allow the researchers to create a supplement formula that was equally effective at lowering the risk for age-related macular degeneration (AMD) and that could be used by anyone whether or not they smoke or formerly smoked.

At the end of the 5-year AREDS2, all participants were given the revised formulation with lutein/zeaxanthin, vitamins C and E, and zinc plus copper and were followed for an additional five years. The researchers wanted to know whether the increased risk of lung cancer seen in those assigned to beta carotene in AREDS continued beyond the end of AREDS2, and whether they could see any long-term benefit of adding lutein/ zeaxanthin to the AREDS2 formula.

In a new report(2), the researchers looked at 10 years of data and concluded that the revised formula with lutein and zeaxanthin not only reduces the risk of lung cancer due to beta carotene but is also more effective at reducing the risk of AMD progressing to late AMD.

The follow-up continued to show that beta carotene nearly doubled the risk of lung cancer for those who had smoked, while there was no increased lung cancer risk for those taking lutein/zeaxanthin. And after 10 years, those originally receiving these two carotenoids in AREDS2 and beyond had an additional 20% reduced risk of AMD progression vs. those assigned to beta carotene.

References

1. Shah S, et al. (OR07-03-22) Adherence to Healthy and Unhealthy Plant-Based Diets and Risk of Breast Cancer Overall and by Hormone Receptor and Histologic Subtypes Among Postmenopausal Women. Presented at the American Society for Nutrition Annual meeting, June 14, 2022
2. National Institutes of Health News Release. NIH study confirms benefit of supplements for slowing age-related macular degeneration. June 2, 2022.

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In the news: Pickle Juice & Muscle Cramps; Pesticides in Fruits & Veggies

Pickle Juice for Muscle Cramps in Cirrhosis

Muscle cramps in people with cirrhosis (liver disease) are common and painful, and treatment options are limited. According to the results of a new study(1), taking small swallows of pickle juice when cramping first starts may be a simple way to reduce the severity of those cramps.

In the 28-day randomized, controlled trial, 82 participants with cirrhosis were assigned to sip either tap water or pickle juice (about 1 tbsp from any dill or kosher pickle product) at the start of cramping.

Those in the pickle juice group had a reduction in the severity of those cramps by 2.25 points compared to just a fraction of a point reduction (0.36 points) for the water group. More patients in the pickle juice group (69%) also reported that the treatment stopped their cramping vs. the water sippers (40%).

The researchers saw no adverse effects with pickle juice. They found no difference in weight changes in the two groups for example, indicating that the pickle juice was not contributing to ascites – a buildup of fluid in the abdomen caused by cirrhosis.

How might pickle juice work? Lab study results suggest that the acetic acid (vinegar) in pickle juice stimulates a nerve reflex (via transient receptor potential or TRP channels) in the back of the mouth and throat. Triggering these channels is thought to send signals to the brain and spinal cord that interrupts electrical activity involved in cramping.

Is there a danger of getting too much salt? Pickle juice is high in sodium which could be a problem for those with high blood pressure and those with heart failure who retain fluid. So, it’s a good idea to check with a doctor first if you have health problems and want to try pickle juice as a remedy.

However, the tbsp. of pickle juice tested in the study doesn’t provide much sodium – only about 25 mg. Also, since it is the acetic acid and not the salt in pickle juice that seems to be responsible for the beneficial effect, it might be reasonable to try a tbsp. of vinegar as an alternative, though vinegar has not been studied for cirrhotic cramps.

Finally, would pickle juice work for other types of    cramps, such as nighttime cramping? While this hasn’t been studied, it’s likely that trials in other groups besides those with cirrhosis will be conducted in the future. For healthy people with exercise-related cramping or nighttime cramping, a tbsp of pickle juice might be worth a try.

Pesticides in Produce

Every year the Environmental Working Group (EWG)(2), a nonprofit organization, releases a report ranking the top twelve nonorganic fruits and vegetables found to have the most pesticide residues – the “Dirty Dozen”. They also put out a list of the 15 “cleanest” fruits and vegies – nearly 70% of which had no detectable pesticide residues.

EWG uses data from 46 fruits and veggies tested by the US Dept. of Agriculture and the FDA. These agencies test food samples in the way people usually eat them: Produce with edible skin like apples are rinsed; Produce with inedible skins such as avocados are peeled.

Consider buying ‘organic’ for those on the “Dirty Dozen” list if possible. However, if ‘organic’ is too costly or unavailable, keep in mind that all foods on that list had pesticide levels that were low and within the limits set by the Environmental Protection Agency. Bottom line: the many health benefits of eating plenty of fruits and veggies outweigh the risk of pesticide exposure.

The “Dirty Dozen”: Strawberries, spinach, kale/collard/ mustard greens, nectarines, apples, grapes, bell and hot peppers, cherries, peaches, pears, celery, and tomatoes.

The “Clean 15”: Avocados, sweet corn, pineapple, onions, papaya, sweet peas (frozen), asparagus, honeydew melon, kiwi, cabbage, mushrooms, cantaloupe, mangoes, watermelon, and sweet potatoes.

References

1. Tapper EB, et al. Pickle Juice Intervention for Cirrhotic Cramps Reduction: The PICm CLES Randomized Controlled Trial. Am J Gastroenterol. Ahead of print April 23, 2022.
2. https://www.ewg.org/foodnews/clean-fifteen.php

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In the news:Lutein/Zeaxanthin May Bolster Memory in Older People with Cognitive Problems

Lutein & Zeaxanthin: Role in the Brain

Though there are hundreds of dietary carotenoids, the pigments found in red, yellow, orange, and dark green fruits and vegies, about six of them account for almost all the carotenoids found in our blood and brain tissue. Of these, lutein and zeaxanthin make up 66 - 77% of the total carotenoids present in the brain.

Here, lutein and zeaxanthin are thought to help protect brain tissue – particularly the brain’s fat content – due to their antioxidant and anti-inflammatory properties.

Studies exploring dietary intake of these carotenoids and cognitive health have generally shown a positive relationship. A higher intake of lutein and/or zeaxanthin, for example, has been tied to a lower risk of experiencing moderate-to-poor cognitive function.

Lutein, Zeaxanthin May Support Visual Memory & Learning

These findings led Australian university researchers to further examine the effects of lutein and zeaxanthin in older individuals with cognitive complaints living in the community.

In the newly published study(1), ninety volunteers aged 40–75 years received either 10 mg of lutein and 2 mg of zeaxanthin daily or a placebo for six months.

The participants were given a battery of computer-based cognitive tasks and questionnaires at the start and end of the study, and always at the same time of day, after eating the same breakfast, and without having consumed any caffeinated drink like coffee.

Compared to the placebo group, lutein and zeaxanthin supplementation was associated with greater improvements in tests measuring visual episodic memory and visual learning at the end of the 6-month period. No other significant differences in the performance on the other cognitive tests or questionnaires was seen.

The findings may be important because visual memory, especially, has been linked to cognitive decline in previous studies. In a 2-year study, for example, better visual memory was associated with a lower risk of cognitive deterioration up to 2 years later. In another investigation, poorer visual memory performance was linked to an increased risk of Alzheimer's disease up to 15 years later.

Visual episodic memory is the memory of everyday events. It’s the ability to recall things such as times, location geography, and associated emotions. In other words, it’s the collection of someone’s past personal experiences that happened at certain times and places.

According to the study authors, “further trials will be essential to clarify the potential benefits of lutein and zeaxanthin supplementation in diverse populations” over time.

While we await the results of future investigations into the cognitive effects of these carotenoids, there are plenty of reasons to consume lutein/zeaxanthin-rich diets.

First and foremost, lutein and zeaxanthin accumulate in the macula of the eye where they are thought to reduce oxidative stress and support eye health. Specifically, they buffer the damaging effects of blue light and protect underlying retinal cells. These carotenoids may also play a role in protecting against the effects of UV exposure on the skin.

As fat soluble nutrients, lutein and zeaxanthin are better absorbed when eaten with a meal containing some oil or fats. Plant sources of lutein such as raw spinach are moderately bioavailable, though cooking improves lutein absorption. Eggs are a very bioavailable source of both lutein and zeaxanthin, and corn is relatively high in zeaxanthin.

References

1. Lopresti AL, et al. The effects of lutein and zeaxanthin supplementation on cognitive function in adults with self-reported mild cognitive complaints: A randomized, double-blind, placebo-controlled study. Front. Nutr. Epub February 17, 2022.

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In the news: Diet and Nighttime Lights Can Impact Sleep & Health

There are plenty of good reasons to strive for a better night’s sleep. For one thing, lack of sufficient sleep can affect concentration, mood, motivation, and judgment. Research also suggests that sleep plays a role in forming and storing memories. And ongoing lack of sleep has been linked to many chronic diseases.

It’s no wonder that research is actively trying to identify factors that could affect sleep quality. In fact, several recent studies suggest what we eat, and night-time lighting can impact sleep and, importantly, our health.

Med Diet Linked to Better Sleep Quality

In a newly published study(1), researchers assessed how closely 500 college students adhered to the Med diet pattern of eating and used a validated questionnaire to score the students’ quality of sleep.

About half of the students had medium or high adherence to the Med diet. Analysis revealed that students with good adherence were more likely to have good sleep quality. Those whose diets more closely matched the Med diet had significantly better subjective sleep quality, with less sleep latency (time to get to sleep), sleep disturbance, and daytime dysfunction.

They also categorized students by chronotype – the internal circadian rhythm that helps determine whether they are a ‘morning person’ (goes to sleep and awakes early), a ‘night person’ (goes to sleep and wakes up later), or intermediate (can be either morning or night type). Students with a morning chronotype were about 6 times more likely to have good adherence to the Med diet vs. the other two types.

A recent review of 20 previous studies on diet and sleep(2) generally agrees with the Med diet findings for students. The reviewers found that diets rich in fiber, fruits, vegetables, and anti-inflammatory nutrients and lower in saturated fat were associated with better sleep quality. They highlighted the Med diet as one that contained the main qualities tied to better sleep.

What attributes of a Med-like diet might contribute to a healthful sleep? One possibility is its anti-inflammatory nature, as increased levels of inflammation have been linked with poor sleep quality in previous studies. The Med diet provides anti-inflammatory nutrients such as antioxidants and omega-3 fatty acids. The diet is also rich in fruits and vegetables which are a source of sleep related melatonin and its precursor serotonin.

Light Exposure During Sleep Can Harm Health

Sleep experts have many suggestions for getting a better night’s sleep: be physically active to reduce stress, stick to a regular sleep schedule, and put away electronic devices before bed since they can interfere with sleep by suppressing melatonin production.

The results of another new study(3)suggest we should also shut the blinds, turn off lights – and keep them off – during sleep for better heart and metabolic health.

A total of 20 young adults participated in this study, which included two nights of sleep in dim light followed by a night of sleep with overhead room lighting.

Even one night’s sleep in a moderately lit room increased insulin resistance the following morning, Heart rate was higher and heart rate variability lower during sleep in the moderately lit room vs. dim light conditions.

Previous evidence has shown that nighttime light, either from outdoor or indoor sources, negatively impacts sleep quality. The results of the current study show that light at night can impair blood sugar and cardiovascular function – both of which raise the risk for heart disease and diabetes.

If you need a night-light for safety, the author suggests using a dim light (red or amber for less stimulation) that’s close to the floor. And if you can’t control outdoor light, try blackout shades or an eye mask.

References

1. Naja F, et al. Adherence to the Mediterranean Diet and its association with sleep quality and chronotype among youth: A Cross-Sectional Study. Front Nutr. Online, Jan 19, 2022.
2. Wilson K, et al. Diet composition and objectively assessed sleep quality: A narrative review. J Acad Nutr Diet. Online, Jan 19, 2022.
3. Light exposure during sleep impairs cardiometabolic function. PNAS. Online March 14, 2022.

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In the news: Flavonoids & Parkinson’s; Impact of Intermittent Fasting

Dietary Flavonoids for Parkinson’s Patients

More than 60,000 Americans are diagnosed with Parkinson’s Disease (PD) yearly and case rates are rising, according to the Parkinson’s Foundation. PD targets the part of the brain controlling movement.

The brain doesn’t make enough of the neuro-transmitter dopamine, which leads to tremors, stiffness, balance problems and difficulty in walking. In later stages of the disease, PD dementia becomes common.

Although not considered a fatal disease, the complications of PD can lead to an increased risk of death. As PD worsens, falls are common, and swallowing can become difficult. Confusion, frailty, and depression also contribute to increased risk of dying.

Now, a newly published study(1) conducted by Penn State and Harvard researchers ties consuming higher amounts of flavonoids to a lower chance of death in those with PD during the 34-year study period. Flavonoids are antioxidants thought to dampen chronic neuro-inflammation.

Previously, Penn State researchers found that in people without PD, eating a flavonoid-rich diet was associated with a lower risk of developing the disease later. Intrigued, the same group decided to study whether flavonoid intake was also tied to a better survival rate in PD patients.

The Study and its Findings

Mining data from participants in two large studies, the researchers evaluated the diets of nearly 600 women and about 650 men who had recently been diagnosed with PD. Total flavonoid intake was analyzed, and they looked at the effects of individual flavonoids too.

After controlling for lifestyle and dietary factors that might affect the outcome of the study, the investigators found that the highest consumers of flavonoids (eating about 673 mg daily) had a substantial 70% greater chance of survival compared to the lowest consumers (eating about 134 mg/day).

Turning to individual types of flavonoids, the analysis showed that eating two types of flavonoids (and the consumption of berries and red wine) were particularly associated with lower risk of mortality.

The highest consumers of anthocyanins (abundant in berries and red wine) had a 66% greater survival rate, while the highest intake of flavan-3-ols (found in apples, pears, tea, and wine) was associated with a 69% greater survival rate.

The study raises the possibility that eating more servings of flavonoid-rich foods weekly may support life expectancy in those with PD.

Intermittent Fasting Works

Different weight loss approaches work for different people. Whether it’s counting calories or upping physical activity combined with a healthy diet, the important thing is that it helps shed and maintain weight. But for those embracing intermittent fasting as a way to keep weight down, a new study confirms that this strategy brings substantial health benefits.

A large review(2) of 130 clinical trials showed that intermittent fasting was a good strategy for shedding weight with improvements in body weight, body fat, LDL cholesterol, triglycerides and insulin resistance.

For more info on this weight loss strategy, see: https://www.health.harvard.edu/heart-health/time-to-try-intermittent-fasting).

References

1. Zhang X, et al. Intake of flavonoids and flavonoid-rich foods, and mortality risk among individuals with Parkinson disease: A prospective cohort study. Neurol. Epub January 26, 2022.
2. Patikorn C, et al. Intermittent Fasting and Obesity-Related Health Outcomes: An Umbrella Review of Meta-analyses of Randomized Clinical Trials. JAMA Netw Open. 4(12):e2139558, Dec. 17, 2021.

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In the news: Sugary Diets May Raise Alzheimer’s Risk

Alzheimer’s: Background and Research

Researchers do not fully understand which changes in the aging brain may cause Alzheimer’s disease. Is it due to an accumulation of beta-amyloid protein? Is the culprit a buildup of tau protein inside neurons? Or, as emerging evidence suggests, is Alzheimer’s caused by a complex interplay among these two proteins and other risk factors such as impaired brain glucose metabolism and insulin resistance, and chronic inflammation?

Alzheimer’s develops over many years and beta amyloid starts accumulating in the brain decades before it impacts cognition. The earlier stage of development is referred to as ‘preclinical Alzheimer’s’, and researchers study biomarkers like brain beta-amyloid levels in individuals to learn more about how diet and lifestyle may prevent or delay this disease.

One area being explored is the relationship between glucose metabolism and Alzheimer’s(1). We know that the amount and type of carbohydrates we eat influences glucose metabolism. High glycemic index foods (sugar and refined / processed carbs) cause blood sugar to spike and insulin to be released.

Too Much Sugar May Up Alzheimer’s Risk?

Since existing evidence suggests that glucose metabolism may be related to cerebral amyloid, researchers at the University of Kansas Alzheimer’s Disease Center explored the relationship between dietary glycemic measures and cerebral amyloid levels in older individuals with normal cognitive abilities(2).

Using brain scans to determine the burden of amyloid in various regions of the brain, they compared a pattern of habitually eating a high glycemic diet with changes in brain amyloid levels over one year.

Among all the participants, those with the greatest habitual high-glycemic diet scores, higher sugar and total carbohydrate intakes had more amyloid accumulation in an area of the brain (precuneus) associated with body awareness.

The link between these dietary measures and precuneal amyloid was even stronger for participants who already had elevated amyloid at the study’s start. For those individuals, a high glycemic diet was also associated with more amyloid accumulation in the brain area (lateral temporal lobe) that functions in comprehension, hearing, visual processing, and facial recognition, and in an area (posterior cingulate gyrus) thought to be important in cognition.

Interestingly, in a previous study(3) by the same research group, only sugar intake was associated with measures of cognitive performance: higher sugar consumption was linked to poorer mental performance.

Sugary Drinks Tied to Alzheimer’s Risk

Other investigators are looking into the association between sugary beverages and Alzheimer’s. In an analysis(4) of 2600+ Framingham Study participants that were followed for 20 years, researchers found that those who drank 1-7 servings of sugar-sweetened beverages weekly were 1.9 times more likely to develop Alzheimer’s than those who consumed none. Those drinking more than 7 servings of these beverages/week were 2.5 times more likely to develop the disease.

It’s going to require more research before we know whether eating a healthier glycemic diet may reduce the risk of Alzheimer’s. In the meantime, avoiding a high-glycemic index diet makes good sense since it has also been linked to a higher risk of cardiovascular disease, age-related macular degeneration, and cataract formation.

References

1. Alves SS, et al. Review: Insulin resistance as a common link between current Alzheimer's Disease hypotheses. J Alzheimer’s Dis. 82:71-105, 2021.
2. Taylor MK, et al. High glycemic diet Is related to brain amyloid accumulation over one year in preclinical Alzheimer's Disease. Front Nutr. 8:741534, 2021.
3. Taylor MK, et al. A high-glycemic diet is associated with cerebral amyloid burden in cognitively normal older adults. Am J Clin Nutr. 106:1463–70, 2017.
4. Miao H, et al. Sugar in beverages and risk of incident dementia, Alzheimer’s disease and stroke: A prospective cohort study. J Prev Alz Dis. 2:188-93, 2020

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In the news: Vinegar Supports Mental Well-Being; Ginger for Migraine?

Mood-Lifting Effect of Daily Vinegar Use

Vinegar, a product of fermented grains and fruits, is emerging as a natural complement to standard care for several chronic conditions. Daily vinegar intake, for example, has been found to improve blood sugar control in type 2 diabetes and shown to lower blood triglycerides in obese individuals.

Now, new research has examined the impact of daily vinegar intake on mood states and urinary metabolites in healthy college students (aged 18-24 years). The preliminary study, led by nutrition professor Carol S. Johnston of Arizona State University, is the first to link daily vinegar use in healthy young adults with improved mood.

The major ingredient in vinegar is acetic acid, which has a role as an antioxidant in biological systems, including the brain. Theoretically, vinegar may improve mental function by providing an outside source of acetate, a metabolite derived from acetic acid that has been linked to improved cognitive performance in rats.

Prior to the current study, the research team analyzed urinary and plasma metabolites in healthy college students who took red wine vinegar twice daily for eight weeks.

They observed changes in blood levels of certain antioxidant metabolites and the metabolism of tryptophan, a precursor to the stress-alleviating neurotransmitter serotonin.

Those promising initial findings suggested an unexplored role for vinegar in mental health, leading the researchers to carry out the current study(1) – a placebo-controlled trial looking at the impact of daily vinegar intake on mood states and urinary metabolites in healthy college students.

Specifically, they tested whether apple cider vinegar (2 tablespoons diluted in a cup of water twice daily with meals for four weeks) reduced depression scores, based on validated measures of depression, compared to the control treatment.

The vinegar group saw a 20–34% reduction in depression scores, while slight increases in those scores were seen in control group participants.

The pre- and post-study analyses of metabolites in the vinegar group showed changes that are consistent for improved mood, including changes in the metabolism of several amino acids and brain-related pathways. These changes were distinctly different between groups.

Since the study was relatively small, the investigators hope their findings will spur further research to confirm that vinegar – an ordinary cooking staple found in most kitchen cupboards – can bolster mental well-being.

Ginger for Migraines?

Ginger, widely used in traditional medicine, is probably best known clinically for calming nausea and vomiting associated with pregnancy, chemotherapy, post-operatively, and perhaps motion sickness. There is also some data associated with lessening menstrual pain, though not osteoarthritis. Because it potentially reduces nausea and pain it has been studied lately in migraine headache.

In examining the evidence for ginger use in migraine, the author of a new review(2) concludes that there is not yet enough data to recommend it as a first line treatment. However, it may be a useful home remedy for those who, for whatever reason, cannot take established first line medications, according to the author.

One controlled trial found that ginger was no better than placebo for preventing migraine. In other words, ginger did not affect how often migraines occur. However, a meta-analysis (review of studies) found that compared to placebo, a greater percentage of patients were pain free 2 hours after taking ginger. Ginger also reduced the risk of migraine-related nausea and vomiting.

References

1. Johnson CS, et al. Daily vinegar ingestion improves depression scores and alters the metabolome in healthy adults: A randomized controlled trial. Nutrients. 13: 4020, 2021.
2. Andrade C. Review: Ginger for Migraine. Clin Prac Psychopharmacol. 82:6, Dec. 2021.

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In the news: Almonds & the MIND Diet May Help Us Look & Feel Better as We Age

Can Almonds Help Reduce Wrinkles?

The results of several studies conducted at UC Davis suggest that eating almonds may improve facial wrinkles and reduce skin pigmentation – at least modestly so for postmenopausal women with skin that easily sunburns and rarely tans.

The first study(1) included postmenopausal women classified as having sun-vulnerable skin who received either almonds or another equal-calorie (340 kcal) carb snack (cereal bar, granola bar and pretzels) daily.

Significant changes did not show up at 2 months. But after 4 months, wrinkle severity (objectively measured wrinkle depth, skin folds etc.) was reduced by 9% in the almond group vs. 1% in the group getting the carb snack. Overall wrinkle width decreased by 10% vs. 3% in the two groups, respectively.

The most recent investigation(2) was slightly longer and conducted in the same manner as the first study. After 5 ½ months, the almond-eaters (who ranged in age from 51–77) saw wrinkle depth and width decrease by 16%. The intensity of skin pigmentation was also reduced by 20% (meaning a more even skin tone). In contrast, no change in wrinkle severity or skin pig-mentation intensity was seen in the carb snack group (aged 47-84).

In both studies, the women ate an average of 2.1 ounces of raw almonds. That’s roughly two handfuls or about 48 almonds. The researchers theorize that the fatty acids and vitamins E and B3 content of the almonds may be contributing to their skin effects.

Since the participants had to stop consuming other nuts and high potency antioxidant supplements for a month prior to, and during the study, it’s not known whether other kinds of nuts might have similar wrinkle-fighting effects.

One caveat for some is that almonds contain a fair amount of oxalates. Consuming the quantity of almonds tested in the study would be a problem for those who are advised to follow a low oxalate diet because they’re prone to forming calcium oxalate kidney stones.

Follow-up: MIND Diet May Support Better Physical Function with Age

The October issue of Staying Healthy (sbh.com) featured the MIND diet and research linking that diet with slower brain aging. The diet seems to help cognitive resilience--the ability to maintain problem solving and thinking skills even as age-related plaques and tangles accumulate in the brain.

In addition to supporting cognitive abilities, a newly published study found that the MIND diet may also support better muscle strength and less decline in physical function as we age.

In the new study(3), researchers from George Washington University and the National Institute on Aging used data from participants in the Baltimore Longitudinal Study of Aging. The participants’ diets were scored according to how closely they matched the MIND diet.

They also underwent a battery of tests that measure physical performance. They include measures such as body composition, walking speed, standing up from a chair, balance, and grip strength tests. Grip strength is a measure of the maximum force generated by the forearm muscles. It’s a tool for assessing upper body strength and overall strength.

After 6 years, the top 1/3 of participants whose diet most closely resembled the MIND diet, had 57% lower odds of functional impairment, and showed slower physical decline. Additionally, men and women with the highest vs. the lowest MIND scores had greater grip strength: a little over 4 lbs. more for men and close to 3 lbs. more for women.

According to the authors, their findings indicate that more closely sticking to the MIND pattern of eating may help protect functional health in older individuals.

References

1. Foolad N, et al. Prospective randomized controlled pilot study on the effects of almond consumption on skin lipids and wrinkles. Phytother Res. 33:3212-17, 2019.
2. Rybak I, et al. Prospective Randomized Controlled Trial on the Effects of Almonds on Facial Wrinkles and Pigmentation. Nutrients. 13:785, 2021.
3. Talegawkar SA, et al. The Mediterranean - DASH Intervention for Neurodegenerative Delay (MIND) diet is associated with physical function and grip strength in older men and women. Am J Clinc Nutr. 2021.

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In the news: Evidence Expanding for Vitamin K’s Role in Heart Health

Vitamin K Basics

There are two forms of fat-soluble vitamin K: K1 or phylloquinone, and vitamin K2, the menaquinones.

Our diet supplies Vitamin K1 through vegetables (green leafy ones especially), vegetable oils, and some fruits. Meat, dairy, and eggs contain low levels of K1 and modest amounts of vitamin K2. Fermented foods like natto (from fermented soybeans) have high levels of menaquinones, and fermented cheeses are a source as well. The bacteria in our GI tract also produce menaquinones, though it’s not clear how much is absorbed.

Vitamin K is needed for blood to clot, and by a bone-building protein. It’s also required by a protein (matrix GLA-protein) that may play a role in the prevention of vascular calcification – the depositing of calcium in the middle or inner lining of arteries. One hypothesis is that inadequate vitamin K affects the function of matrix GLA-protein leading to greater artery calcification.

Vitamin K for Heart Health? Evidence Growing

New research(1) has found that people eating a vitamin K rich diet have a lower risk – up to 34% lower – of cardiovascular disease related to atherosclerosis “(ASCVD),” a build-up of cholesterol plaque in the walls of arteries causing obstruction of blood flow.

Researchers from Denmark and Australia examined information from more than 50,000 participants in the Danish Diet Cancer and Health Study. After 21 years of follow-up, about 8,700 of these participants (ASCVD-free at the study’s start) were hospitalized due to atherosclerotic conditions affecting the heart or blood vessels.

Since several large population-health studies have linked higher intake of vitamin K to a lower risk for ASCVD, the investigators wanted to see whether dietary vitamin K was associated with ASCVD hospitalizations.

Overall, the study found that participants in the highest vitamin K1 intake bracket (median 192 micrograms daily) had a 21% lower risk of being hospitalized for any ASCVD-related condition vs. those in the lowest intake bracket (median 57 micrograms a day). For vitamin K2, the risk of ASCVD-related hospitalization was 14% lower for the highest vs. lowest intake level.

Specifically, a 14% lower risk of hospitalization due to ischemic heart disease was seen for those in the highest vs. lowest vitamin K1 intake.

Participants consuming the most vitamin K1 also had a 17% lower risk of hospitalization for stroke, and a 34% lower risk of hospitalization for peripheral artery disease.

How Might Vitamin K Influence Heart Health?

Many factors are involved in the development of ASCVD such as inflammation, the metabolic syndrome and arterial calcification. Vitamin K is thought to influence cardiovascular health in several ways including reducing inflammation and helping to block arterial calcification.

Vascular calcification is one risk factor for coronary heart disease because it reduces artery elasticity. Healthy, flexible arteries can expand and briefly store blood from each heartbeat to help move blood to all areas of the body.

Both K1 and K2 are needed for good health. Some, though not all studies suggest that consuming adequate levels of K2 may be particularly important for artery health. The authors of the present study point out that their database of vitamin K content of foods is very comprehensive for vitamin K1, while there is much less information available for vitamin K2 food content.

Note: If you take the blood-thinning medication Coumadin, be sure to inform your doctor before increasing vitamin K intake through foods or supplements. Maintaining consistent intakes of vitamin K is important for this drug to work properly.

References

1. Bellinge JW, et al. Vitamin K intake and Atherosclerotic Cardiovascular disease in the Danish Diet Cancer and Health Study. J Am Heart Assoc. Epub Aug. 7, 2021.

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In the news: Birth & Evolution of the MIND Diet for Brain Health

What is the Memory and Aging Project?

In 1997 researchers from Rush University Medical Center started the Memory and Aging Project (MAP). They wanted to study common chronic conditions of aging and especially cognitive decline and the risk for Alzheimer’s disease in seniors in the Chicago area.

Participants, who had no dementia at the start of this ongoing study, undergo annual neurological exams and provide information about their diets and lifestyle. They also agree to post-mortem brain tissue exams. The overall goal of MAP is to identify factors that may help maintain memory and thinking skills(1).

MIND Diet for Better Cognitive Health

Analyses of two trials on the Mediterranean (Med) diet and the blood pressure lowering DASH diet showed protective effects of these diet on cognitive decline, leading the Rush investigators to study the diets in MAP participants too They observed that higher DASH and Med diet scores were tied to slower rates decline(2).

The researchers noted that neither diet closely reflected nutrition research specifically for dementia prevention. So, they devised a diet based on the Med and DASH diets but modified to stress the most compelling scientific findings in the diet-dementia field.

The new hybrid diet emphasizes foods that impact brain health. For example, studies suggest that green leafy vegetables and berries are linked to greater protection vs. other fruits and veggies, and MIND scores them higher. They named the diet MIND (Mediterranean-DASH Diet Intervention for Neuro-degenerative Delay).

MIND Linked to Slower Brain Aging

Exploring the effects of MIND in 960 MAP participants for over nearly 5 years, the research team found that MIND scores were substantially linked to slower cognitive decline in all five of the brain domains tested.

Those who followed MIND most closely (the top 1/3 of diet scores vs. the lowest 1/3 scores) had slower brain aging that was equivalent to being 7.5 years younger in age(3).

New Study: MIND and Brain Resilience

The results of the newest MAP-related study suggest that participants who followed MIND fared better cognitively even if they had signs of brain pathologies(4). The study focused on 569 MAP participants who were no longer alive, and who had up to date dietary information, had undergone cognitive testing close to their death, and for whom there was complete autopsy data.

The Rush team found that a higher MIND diet score was associated with better cognitive function and slower cognitive decline – findings that were independent of brain pathologies related to Alzheimer’s.

As the brain ages, sometimes abnormal clumps of proteins called amyloid plaques and tangles accumulate. These protein deposits are characteristic of Alzheimer’s and can interfere with problem solving and thinking skills. However, not everyone with these brain pathologies experiences cognitive dysfunction – some are able to maintain function despite damage from the accumulation of plaques and tangles. This ability is known as cognitive resilience – performing better than expected given accumulated brain pathologies. The investigators think that MIND may contribute to cognitive resilience.

What Exactly is the MIND Diet?

The MIND diet score has 15 components, including 10 brain-healthy food groups (green leafy vegetables, other vegetables, nuts, berries, beans /legumes, whole grains, fish, poultry, olive oil, and wine) and 5 less healthy food groups (red meat, fried and fast foods, pastry and sweets, butter, and cheese) to limit or avoid.

Since the evidence for MIND is based on observational studies so far, intervention studies are needed to confirm its brain benefits. In the meantime, to learn more details about MIND: https://www.mayoclinic.org/healthy-lifestyle/nutrition-and-healthy-eating/in-depth/improve-brain-health-with-the-mind-diet/art-20454746

References

1. Bennett DA, et al. Overview and findings from the Rush Memory and Aging Project. Curr Alzheimer Res. 9: 646–663, 2012.
2. Tangney CC, et al. Relation of DASH- and Mediterranean-like dietary patterns to cognitive decline in older persons. Neurology. 83:1410–1416, 2014.
3. Morris MC, et al. MIND diet slows cognitive decline with aging. Alzheimers Dement. 11:1015-1022, 2015.
4. Klodian D, et al. Mind diet, common brain pathologies, and cognition in community-dwelling older adults. J of Alzheimer’s Dis. 83:683, 2021.

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In the news: All Types of Coffee & Tai Chi May Help Combat Fatty Liver Disease

Follow-up on Fatty Liver: Coffee & Tai Chi

Last month’s Staying Healthy focused on Nonalcoholic Fatty Liver Disease (NAFLD) and summarized a study suggesting that the Med diet with extra polyphenols can help fight the build-up of fat in the liver. To follow-up, a new study indicates that compounds in coffee might also be of help in combatting this condition and other chronic liver problems as well. Another study found that Tai Chi is just as good as aerobics and weight training to slim down the waistline.

Previous studies have linked coffee drinking with lower rates of chronic liver disease, but not much is known about the effects of different types of coffee, including decaf, instant and ground coffees, which vary in chemical composition. Researchers from the Universities of South Hampton and Edinburgh in the UK set out to learn more about the effects of different coffee types on chronic liver disease(1).

To do this, they used data from nearly half a million participants in the UK Biobank study who were followed over 10 years. Of the participants more than ¾ drank coffee regularly (median intake: 2 cups/ day).

Comparing coffee drinkers (all types of coffee and amounts combined) vs. non-drinkers, the investigators found 21% decreased risk of chronic liver disease, and a 20% reduction in risk of chronic or fatty liver disease. The risk of dying from chronic liver disease was reduced by 49%.

The associations for each coffee type separately (decaf, instant and ground including espresso) were similar to the associations seen for all types of coffee combined, though ground coffee appeared to have the largest effect.

The maximum protective effect was seen at around 3-4 cups daily. Ground coffee has high levels of certain compounds (kahweol and cafestol) which have been shown to be effective in animal studies of chronic liver disease. Caffeine and chlorogenic acids in coffee may also contribute to coffee’s beneficial effects on the liver. But the authors point out that since a protective effect was seen for all types of coffee (including decaf), there is likely a complex relationship involving more than one of coffee’s active compounds.

Some people avoid coffee because they may be sensitive to caffeine, feeling that it makes them jittery. The good news: this study suggests that decaf can be protective too. As studies suggest that those at risk of glaucoma should keep caffeine intake low, decaf is a good choice for those at risk of this condition too.

For those who worry that caffeine (in moderate amounts, 2 cups/day) can cause heart arrhythmias, a new study from UC San Francisco – the largest investigation of its kind – found no evidence that caffeine consumption increases the risk of abnormal heart rhythms even in those genetically disposed to metabolize coffee differently(2).

Tai Chi for Controlling the Waistline

Abdominal obesity (larger waistline, higher waist-to- hip ratio and BMI) appears to be more of a risk for fatty liver disease than generally being obese or over-weight. But conventional exercise programs to shrink the waist and drop weight can be daunting for some with limited mobility, arthritis, or medical problems. Enter tai chi – a gentler practice suitable even for inactive, overweight, and older people.

Researchers in Hong Kong(3) assigned nearly 550 people with waistlines greater than 35.4 “for men and 31.5” for women to one of 3 groups: no exercise, brisk walking plus weights (3x weekly), or tai chi (3 hours per week) for 12 weeks.

Compared to no exercise, the tai chi group lost an average 0.7” around the waist while the conventional exercisers lost 0.5” on average. Both exercise groups lost weight and had better levels of good HDL cholesterol. Bottom line: Practicing tai chi, drinking coffee, and following a polyphenol enriched Med diet may be a potent trio to help beat fatty liver disease.

References

1. Kennedy OJ, et al. All coffee types decrease the risk of adverse clinical outcomes in chronic liver disease: a UK Biobank study. BMC Public Health. 21:970, 2021.
2. Kim E-J, et al. Coffee consumption and incident tachyarrhythmias reported behavior, Mendelian randomization, and their interactions. JAMA Intern Med. Published online July 19, 2021
3. Siu PM, et al. Effects of tai chi or conventional exercise on central obesity in middle-aged and older Adults : A three-group randomized controlled trial. Ann Intern Med. Published online May 2021.

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In the news: Flavonoids Help Fight Cognitive Decline? Vitamin K Linked to Lower Risk of CVD

More Evidence that Flavonoids Might Help Prevent Cognitive Decline

Looking to better the odds of keeping your thinking skills as you age? The results of a new study suggest that eating more flavonoid-filled fruits and veggies may help reduce your risk of age-related cognitive decline(1).

The study, which followed a large number of men and women over a long period of time, reinforces the findings from shorter, smaller trials that flavonoids have substantial potential to help maintain mental abilities as we grow older.

For the study, Harvard researchers analyzed dietary flavonoid intake in about 49,000 women and close to 28,000 men and collected data about their self-reported subjective cognitive decline.

Those who consumed the highest level of total flavonoids (600 mg daily on average) had about a 20% lower risk of subjective cognitive decline compared to their peers who ate the least (roughly 150 mg per day).

Of the many types of flavonoids, flavones (found in orange or yellow fruits and veggies and some spices), flavanones (citrus fruits), and anthocyanins (berries, grapes) were associated with the most protective effect.

Eating at least a half serving daily on average of flavonoid-rich foods like oranges, grapefruit, citrus juices, apples, pears, peppers, strawberries and celery and bananas was significantly associated with a lower likelihood of self-reported cognitive decline.

Flavonoids may act by helping to counter oxidative stress and inflammation, as well as supporting good blood flow to the brain.

It may be time to add eating more flavonoid-rich foods to the list of factors that appear to protect against age-related cognitive decline – factors such as staying physically active, keeping mentally and socially engaged, getting adequate sleep, and following a healthy diet like the Mediterranean-style way of eating.

Vitamin K Linked to Lower Risk for CVD

Atherosclerotic cardiovascular disease (CVD), more commonly known as hardening of the arteries, is caused by a build-up of cholesterol plaque in the walls of arteries. The plaque becomes calcified and can eventually lead to obstructed blood flow.

Vitamin K plays many roles in the body from proper blood clotting to the mineralization of bones. It also is needed to activate a protein found in blood vessel walls that regulates the accumulation of calcium in the vessel wall.

In a recently published study(2), Australian researchers analyzed data from a large group of Danish citizens who began the study with no prior atherosclerotic CVD and for whom vitamin K intake was recorded at the study’s start. During 21 years of follow-up, they looked for hospital admissions due to atherosclerotic CVD.

Vitamin K comes in two forms: K1 and K2 and both forms were associated with risk of hospitalization due to atherosclerotic CVD. Participants with the highest vs. the lowest intakes of vitamin K1 had a reduced risk of 21%, while those consuming the highest amount of vitamin K2 saw a 14% risk reduction.

Vitamin K1 (called phylloquinone) is mainly found in green leafy veggies as well as olive oil and soybean oil. Vitamin K2 (menaquinone) is found in small amounts in chicken, butter, egg yolks, cheese, and fermented soybeans or ‘natto’.

According to the authors, the similar risk reductions of vitamin K, and K2, despite very different dietary sources, highlights the potential importance of vitamin K for atherosclerotic CVD prevention.

References

1. According to the authors, the similar risk reductions of vitamin K, and K2, despite very different dietary sources, highlights the potential importance of vitamin K for atherosclerotic CVD prevention.
2. Bellinge JW, et al. Vitamin K Intake and Atherosclerotic Cardiovascular Disease in the Danish Diet Cancer and Health Study. J Am Heart Assoc. Originally published Aug 7, 2021.

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In the news: Fighting Fatty Liver Disease with a Twist on The Med Diet

What is Non-Alcoholic Fatty Liver Disease?

Nonalcoholic fatty liver disease (NAFLD) is now one of the most common chronic liver conditions in the US, estimated to affect 1 out of 4 American adults.

Simply put, NAFLD is caused by a build-up of fat in the liver that’s not related to over consumption of alcohol. A healthy liver contains little fat, so the excess fat stored inside liver cells makes it harder for this organ to function. NAFLD is most often found in people who are overweight or obese – especially those with a large waist circumference, the “apple-shaped” body.

So, is a fatty liver dangerous for your health? Not in the early stages, but it can pose health problems if it’s ignored and progresses. NAFLD is also associated diabetes, cardiovascular disease, and obstructive sleep apnea. The 4 general stages of NAFLD-related liver disease include: • simple fatty liver (steatosis) – a largely harmless build-up of fat in the liver cells • non-alcoholic steatohepatitis (NASH) – a more serious form of NAFLD, where the liver has become inflamed • fibrosis – persistent inflammation causes scar tissue around the liver and nearby vessels, but the liver function is still relatively normal • cirrhosis– the most severe stage where the liver shrinks and becomes scarred after years of inflammation and the damage is permanent

Strategies to Fight NAFLD

As of now, there is no drug treatment for NAFLD and the tried-and-true way to combat NAFLD is weight loss. That means increasing physical activity and eating better and eating less.

A recent Medscape article(1) summarized the new 2020 American Gastroenterological Association (AGA) guidelines for how much total body weight loss is needed to turn around various stages of NAFLD-related disease: losing more than 5% can decrease liver steatosis, greater than 7% potentially leads to resolution of nonalcoholic steatohepatitis, and losing more than 10% possibly allows for reducing fibrosis, or at least stabilizing the condition.

Inflammation and oxidative stress are the major risk factors involved in NAFLD progression. So, in terms of specific diets for taming NAFLD, the Mediterranean (Med) diet with its anti-inflammatory and antioxidant effects, has been put forward by the AGA who also advises limiting red meat and sugary beverages.

Now, a new study(2) suggests that the Med diet with a new twist – extra polyphenols – can improve NAFLD. The study enrolled more than 290 people with abdominal obesity and elevated blood fats who were assigned to one of three groups: one based on healthy dietary guidelines, a standard Med diet and the standard Med diet plus extra polyphenols (“greens”).

Calories were restricted in all three groups, and both Med diet groups got extra walnuts daily, providing 440 mg of polyphenols. However, the Med + diet group received even more polyphenols – 800 mg more in the form of three glasses of green tea daily, plus Mankai (Wolffia globosa a water plant) in the form of frozen cubes made into a green shake dinner replacement.

After 1½ years, NAFLD declined to about 55% in the non-Med diet group, 48% in the standard Med group, and 32% in the Med+ group.

Both Med groups achieved similar weight loss, more than the non-Med group. But the Med + group was found to have lost more liver fat (-39%) compared to the standard Med diet group (-20%) and the healthy diet group (-12%).

The researchers found that he degree of liver fat loss was associated with polyphenols, lower red and processed meat, better blood folate levels, improved lipid biomarkers and changes in gut microflora.

Almost 90% of the participants stuck with their diets. If the extra dinner shake seems daunting, however, following the Med diet, watching calories, including walnuts, and cutting out red and processed meats should go a long way to halting NAFLD.

References

1. Balistreri WF. The Mediterranean Diet, Already Beneficial in NAFLD, Gets a Green Boost. Medscape May 18, 2021.
2. Meir AY et al. Effect of green-Mediterranean diet on intrahepatic fat: the DIRECT PLUS randomized controlled trial. Gut. 0:1–11, 2021.

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In the news: Adding Some Sardines, Mushrooms & Green Leafy Veggies Pays Dividends

Small Changes May Lead to Big Health Gains

Sometimes making small changes in one’s diet can add up to big benefits. Several new studies illustrate this perfectly, showing that sardines, mushrooms, and green leafy veggies are easy additions to the diet that can impact health in significant ways.

Sardines Could Help Prevent Type 2 Diabetes

As an oily fish, sardines are well known as a rich source of heart-healthy omega-3 fatty acids. But regularly eating this tiny fish may help prevent the development of type 2 diabetes according to university researchers in Spain.

In the study(1), researchers put patients 65 and older who were diagnosed with pre-diabetes on a nutritional regimen aimed at reducing diabetes risk. Only one group, however, was assigned to add two cans of sardines (packed in olive oil) weekly to the diet.

At the study’s start 37% of the sardine group were deemed to be very high risk for diabetes, while at the study’s conclusion one year later only 8% remained in that category. In contrast, 27% of those in the non-sardine group were classified as very high risk to begin with, while 22% were still in that category after a year. Sardine consumers also saw improvements in insulin resistance and other biomarkers of heart health.

Study participants ate the whole sardine which contains calcium, vitamin D and the heart-healthy amino acid taurine in addition to omega-3 fats. Sardines are inexpensive and readily available, making their addition to a healthy diet a practical strategy to consider for lowering type 2 diabetes risk.

Mushrooms May Lower the Risk of Cancer

Results from several large-scale epidemiologic studies suggest that regular mushroom intake is tied to a lower risk of developing various cancers. For example, an analysis of two large and long studies which was published in 2019(2) reports that eating mushrooms at least once or twice weekly is associated with an 8% lower risk of prostate cancer. Consuming them 3 or more times a week is tied to a 17% lower prostate cancer risk.

Now, a review and meta-analysis(3) of 17 studies involving about 19,500 cancer patients found that people who included any variety of mushrooms into their daily diets had a lower cancer risk. Breast cancer risk was particularly associated with mushroom intake, but a lower risk cancer overall was seen.

Specifically, those who consumed roughly ¼ to ½ cup of mushrooms daily had a 45% lower risk of cancer than non-consumers of mushrooms. The researchers were not able to pin down the ‘best’ type of mushrooms, as many of the individual studies didn’t identify or quantify which mushrooms were consumed. Importantly, eating any kind of mushroom on a regular basis was associated with reduced risk.

Commonly consumed mushrooms include white button, shitake, maitake, oyster, cremini, and portabella. Shitake, maitake and oyster mushrooms have higher levels of a compound called ergothioneine which is a potent antioxidant. Mushrooms also contain fiber and selenium among other nutrients.

Nitrate-Rich Veggies Tied to Heart Health

Dietary nitrates, found in leafy green and other veggies, including beets and celery, are the precursors to nitric oxide – a compound that helps expand blood vessels for healthy blood flow. Looking at diet and health data of over 50,000 people followed for more than two decades, a new study(4) found that eating nitrate-rich veggies is tied to better blood pressure and a reduction in risk of heart disease.

Notably, adding only about 1 cup daily of raw green leafy veggies – roughly ½ cup cooked--provided long term heart benefits.

References

1. Diaz-Rizzolo DA, et al. Type 2 diabetes preventive effects with a 12-months sardine-enriched diet in an elderly population with prediabetes: An interventional, randomized, and controlled trial. Clin Nutr: 40:2587-98, 2021.
2. Zhang S, et al. Mushroom consumption and incident risk of prostate cancer in Japan: A pooled analysis of the Miyagi Cohort and the Ohsaki Cohort Studies. Int J Cancer. 146, 2712–20, 2020.
3. Ba DM, et al. Higher Mushroom Consumption Is Associated with Lower Risk of Cancer: A Systematic Review and Meta-Analysis of Observational Studies. Adv Nutr. Published online Mar, 2021.
4. Bondonno CP, et al. Vegetable nitrate intake, blood pressure and incident cardiovascular disease: Danish Diet, Cancer, and Health Study. Eur J Epidemiol. Published online Apr, 2021./li>

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In the news: Research Roundup: From Acupuncture for Migraine to Olive Oil & ‘Good” Carbs for the Heart

Americans Packed on Pounds During Lockdowns

It’s no surprise that with less physical activity and eating more comfort food during COVID-19 related shelter-in-place orders, Americans gained almost 2 pounds monthly during 2020.

According to researchers from UC San Francisco who monitored over 7,000 weight measurements from nearly 270 people in 37 states from Feb. 1st-June 1st, participants in the study chalked up a weight increase of more than a half-pound every 10 days(1). For some, that could add up to a gain of 20 lbs. last year.

If you’re trying to shed pandemic-related pounds and need some help, WW (formerly Weight Watchers) and the app NOOM both have supporting data for effective weight loss and could be useful. Although the two programs take slightly different approaches, both help users choose lower calorie, more nutritious foods, and encourage better portion control and daily physical activity. To learn more about the programs: https://www.medicalnewstoday.com/articles/noom-vs-weight-watchers#effectiveness

Olive Oil: Even ½ Tbs. Daily May Make Difference

While Americans consume less olive oil per person than in Mediterranean regions, a study by Harvard researchers suggests that even small amounts of the oil can help the heart(2).

The researchers looked at data from almost 93,000 participants of two large studies who were free of heart disease at the study’s start and followed for 24 years. After adjusting for major diet and lifestyle factors, those with higher olive oil intake of at least 1/2 tablespoon (7 grams) daily had a 15% lower risk of total cardio-vascular disease (CVD) and a 21% lower risk of coronary heart disease (CHD) vs. non-oil consumers.

Replacing 5 grams of margarine, butter, mayonnaise, or dairy fat with the equivalent amount of olive oil was associated with a 5-7% lower risk of total CVD and CHD, according to the authors’ estimate.

Focus on “Good” Carbs for Better Heart Health

If olive oil is heart-friendly, the kind of carbs you choose can make a difference in heart health too. Foods with a high glycemic index (GI) such as white bread, white rice, potatoes (no skin) and sugary drinks raise blood glucose levels more rapidly than lower GI foods or “good” carbs such as whole grains, beans, green vegetables and most fruit. Glycemic load not only measures how quickly a food makes glucose enter the bloodstream but how much glucose per serving or portion size it delivers.

In a new study(3), researchers looked at data from nearly 138,00 participants from 20 countries and found that eating the highest GI diet considerably increased the risk of death and cardiovascular disease (CVD) in both those with CVD and healthy individuals, especially overweight or obese people. The results for glycemic load were similar but only applied to those who already had CVD when they enrolled in the study.

Acupuncture vs. Drugs for Migraine Prevention

Italian researchers report that acupuncture could be as effective as pharmacologic treatments in helping to prevent recurring headaches in episodic migraine(4) – a condition diagnosed when a person experiences headaches less than 14 days monthly (vs. chronic migraine with 15 or more headaches per month).

In this randomized trial, 148 patients suffering from migraines were assigned either to treatment with 12 sessions of acupuncture or to a group treated with the most appropriate medication for each patient.

After 4 months, the frequency of headaches significantly decreased to the same extent in both groups – both had a similar reduction in the number of days with migraines during the treatments. About 34% of patients showed a reduction of headache days by at least 50% after the treatments. According to the authors, the data suggested that acupuncture was slightly superior to the pharmacological treatment in participants’ compliance and rate of adverse events.

References

1. Lin AL, et al. Body weight changes uring pandemic-related shelter-in-place in a longitudinal cohort study. JAMA Network Open. 4:e212536, 2021.
2. Guasch M, et al. Olive Oil Consumption and Risk of Cardio-vascular Disease. Circulation. 141:AP509, 2020.
3. Jenkins JA, et al. Glycemic index, glycemic load, and cardio-vascular disease and mortality. NEJM. 384:1312-1322, 2021.
4. Giannini G, et al. A randomized clinical trial on acupuncture versus best medical therapy in episodic migraine prophylaxis: The ACUMIGRAN Study. Front. Neurol. Epub, January, 2021.

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In the news: Lessons from a Tanzanian Diet Study; Carotenoids and Breast Cancer?

Lessons from Tanzania: Better Diet, Less Inflammation & a Healthier Immune System

A study(1,2) conducted by a team of Dutch, German and Tanzanian researchers reports that eating a typical Western diet versus a more traditional diet is associated with slow, prolonged inflammation – a condition that underlies many chronic diseases. These findings help explain why choosing more whole, plant-based foods is a healthier way to go.

In Tanzania, moving from the countryside to cities leads to dietary changes and is accompanied by a rapid increase in chronic diseases – a pattern observed long ago in the US as well. The research team wanted to look at how this rural to urban change in eating habits affects the immune system and inflammation. The traditional rural Tanzanian diet is rich in whole grains, fiber, fruits and vegetables, while the urban, “Westernized” diet contains more processed foods and saturated fats.

The researchers focused on healthy Tanzanians living in a specific city and a group living in the countryside. From participants’ blood samples, the scientists used the latest tools to unlock the function of the immune system and the factors that influence its activity – looking at active RNA molecules and the composition of metabolic products in the blood.

Comparing the blood analysis results of the two groups, they found that metabolites derived from food had an effect on the immune system.

The rural-living group had higher levels of flavonoids and other anti-inflammatory substances in their blood. In contrast, the urban-residing group had immune cells that produced more inflammatory proteins. They also had increased levels of metabolites that are involved in cholesterol metabolism.

In short, the urban dwellers had a more activated immune system and inflammation, which may increase the risk for chronic diseases such as heart disease. In comparison, the traditional Tanzanian diet had a beneficial effect on inflammation and the functioning of the immune system.

Carotenoids: Role Preventing Breast Cancer?

While diet has been linked to development of breast cancer, a new study has focused on women at high-risk for breast cancer and carotenoids – the pigments found in fruits and veggies(3,4).

Harvard researchers measured carotenoids in plasma at an early follow up of the Nurses’ Health Studies for 1,919 women who later developed breast cancer and 1,695 controls who did not. To determine who was at high-risk for breast cancer, a genetic risk score was developed. The density of breast tissue was also determined by pre-diagnosis mammograms. Research has shown that dense breasts can be twice as likely to develop cancer as non-dense breasts and can make it harder for mammograms to detect breast cancer.

The researchers found that, overall, plasma carotenoid concentrations above 142 micrograms/deciliter were associated with a 20% lower breast cancer risk. The association was seen with estrogen receptor positive, but not estrogen receptor negative, breast cancer.

The association was more pronounced in high-risk women. For women with a high genetic risk score, having the highest circulating carotenoids led to a 28% lower risk for breast cancer. Among women with high mammographic dense tissue, the risk was 37% lower for those with the highest plasma carotenoids.

The American Institute for Cancer Research advises women to eat a diet high in veggies, fruit, whole grains and legumes (beans, lentils), and to limit processed foods, sugary drinks and alcohol. The results of this study emphasize the importance of carotenoid-rich fruits and veggies, especially for high-risk women.

References

1. Godfrey S, et al. Urban living in healthy Tanzanians is associated with an inflammatory status driven by dietary and metabolic changes. Nature Immunology. 22 : 287, 2021.
2. Radboud University Medical Center News. ”Less Inflammation with a Traditional Tanzanian Diet Than with a Western Diet”. https://www.radboudumc.nl/en/radboud-institute-for-health-sciences.
3. Peng C, et al. Circulating carotenoids and breast cancer among high-risk individuals. Am J Clin Nutr. 113: 525–533, 2021.
4. McTiernan A. Editorial. Dietary prevention of breast cancer in high-risk women: role of carotenoids. Am J Clin Nutr. 113:499-500, 2021.

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In the news: Coffee May Lower Heart Failure Risk; Oily Fish and Type 2 Diabetes

Coffee May Lower Risk for Heart Failure

There’s good news for those who love coffee. A newly published study reports that drinking at least one or more cups of caffeinated (but not decaffeinated) coffee daily is associated with a lower risk of developing heart failure(1), a common condition in older individuals. Heart failure affects over 6 million Americans, with an estimated 960,000 new cases diagnosed each year.

Using a type of artificial intelligence (a machine learning model from the American Heart Association) as a method to analyze data, researchers looked at coffee consumption and heart failure in three large, well-known studies that included more than 21,000 participants who were followed for at least a decade. The studies included the Framingham Heart Study, Cardiovascular Health Study, and the Atherosclerosis Risk in Communities Study.

Across all 3 of these population studies, people who drank more coffee had a lower long-term risk of heart failure.

In the Atherosclerosis Risk in Communities Study, there appeared to be about a 30% reduction in risk with the consumption of at least 2 or more cups daily versus no coffee consumption3. Among those in the Framingham and Cardiovascular Health studies, the risk of heart failure fell by 5%-12% per cup of coffee per day, compared to people who drank none3.

Using machine learning to analyze data (the method used in this study) is a new and promising tool for nutrition research. The benefit of this approach.is that it can steer researchers toward the strongest risk factors to examine. In this case, coffee ranked in importance alongside age, blood pressure, heart rate and weight for their associations with heart failure(2,3).

Some people are sensitive to caffeine, linking its intake to heart palpitations. Drinking too much caffeine may also cause jitteriness and sleep problems. But for most people, a link between 2 cups of java daily and a reduced risk for heart failure is welcome news.

Oily Fish May Be an Ally in Preventing Type 2

Cold water, oily fish are those that contain a good amount of omega-3 fatty acids. Examples include sardines, herring and anchovies among the smaller fish, as well as salmon, trout, mackerel, tuna and swordfish.

Eating oil-rich fish (but not non-oily fish) is tied to a lower risk for developing type 2 diabetes, according to a newly published study(4).

Researchers used information from over 390,000 middle-aged and older people residing in the United Kingdom (participants in the UK Biobank) to evaluate the association between oil and non-oily fish consumption and type 2 diabetes – the largest study to date to examine the fish-diabetes link.

Participants who ate either 1, or 2 or more oily fish servings per week had a lower risk – 22% lower – of type 2 diabetes compared to those who ate none. No significant link was observed for non-oil fish consumption.

A significant 9% lower incidence of type 2 was seen for those who reported regularly taking a fish oil supplement vs non-users at the study's start, and an 18% reduced risk for those reporting fish oil use during the study.

The authors recommend fresh oily fish rather than fish oil supplements but note that fish oil may be an alternative for those who can’t add these fish to their diet.

References

1. Stevens LM, et al. Association between coffee intake and incident heart failure risk. Circ Heart Fail. 14:e006799, 2021.
2. Vest AR. Editorial: Can two coffees a day keep the heart doctor away? Circ Heart Fail. 14:e008297, 2021.
3. American Heart Association News, Feb. 9, 2021. https://www.heart.org/en/news/2021/02/09/coffee-may-help-reduce-risk-for-heart-failure Chen G-C, et al. Association
4. Chen G-C, et al. Association of oily and non-oily fish consumption and fish oil supplements with incident type 2 Diabetes: A Large Population-Based Prospective Study. Diabetes Care. Epub Jan. 11, 2021.

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In the news: Vitamins C & E and Parkinson’s; Flavonoids Tied to Lower PAD Risk

Vitamins C & E Tied to Lower Parkinson’s Risk

Parkinson's disease, characterized by progressive loss of coordination and movement, is a nervous system disorder that affects mostly dopamine-producing nerve cells in the substantia nigra area of the brain. Dopamine is a neurotransmitter that carries signals between nerve cells and is involved in regulating movement.

Oxidative stress plays an important role in the degeneration of dopamine-producing neurons in the substantia nigra. Antioxidants are believed to help counter oxidative stress that can lead to this loss of dopamine. A new study from Swedish researchers suggests that long-term intake of antioxidant vitamins C and E may lower the risk of developing Parkinson’s(1).

The researchers collected diet, health and lifestyle information from over 41,000 men and women who were free of Parkinson’s disease at the study’s start and were followed for an average of about 18 years. The participants intake of vitamins C and E and beta-carotene was assessed. The relationship between total (nonezymatic) antioxidant capacity (NEAC) of the diet and Parkinson’s risk was also analyzed.

Comparing participant groups with the lowest versus highest intake of C or E, they found that higher intake was associated with a 32% reduction in risk for Parkinson’s. Those who consumed the highest level of both vitamins together had a 38% risk reduction. No association with Parkinson’s risk was seen with dietary beta-carotene consumption or NEAC.

While the findings hold promise, one limitation of the study was that the dietary information was collected only at the beginning of the study. This does not ensure that people had not changed their diet over the course of the study. Nonetheless, it is possible that focusing on vitamin C and E-rich foods might help lower the risk of developing this disease later in life.

Sunflower seeds, almonds, spinach, avocados, squash, kiwifruit, trout, shrimp, olive oil, wheat germ oil, and broccoli are some of the foods high in vitamin E. Good sources of vitamin C include guavas, bell peppers, kiwifruit, strawberries, oranges, papayas, broccoli, tomatoes, kale, and snow peas.

Flavonoids May Help Protect Against PAD

Peripheral artery disease (PAD) is a common circulatory problem in which narrowed arteries reduce blood flow to the limbs – the arms, but most often the legs. Atherosclerosis is the most common cause of PAD, meaning that plaque has built up inside the artery walls.

Danish researchers recently analyzed data from 55,000 + participants of the Danish Diet, Cancer, and Health Study without PAD to see whether there is a relationship between intake of dietary flavonoids and hospitalizations for PAD(2).

The participants were followed for approximately 21 years, during which 2,131 had been hospitalized for the condition.

Compared with the lowest flavonoid intake (174 mg/day), an intake of 1000 mg/day was linked with a 32% lower risk of any PAD hospitalization, a 26% lower risk of atherosclerosis, a 28% lower risk of an aneurysm and a 47% lower risk of a hospitalization for other peripheral vascular disease.

While more research is necessary to determine whether flavonoids may help protect against PAD, these compounds have been shown to improve the function of the lining of arteries (endothelial function) and decrease inflammation and blood pressure. These healthy compounds are abundant in foods and beverages such as fruits, vegetables, dark chocolate, tea, and red wine.

References

1. Hantikainen E, et al. Dietary antioxidants and the risk of Parkinson Disease: The Swedish National March Cohort. Neurology. Epub Jan 6, 2021.
2. Bondonno P, et al. Higher habitual flavonoid intakes are associated with a lower risk of peripheral artery disease hospitalizations. Am J Clin Nutr. 113:187-199, 2021.

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In the news: Support for Urinary Tract Health

Cranberry May Help Women with Overactive Bladder

Cranberry is known for helping to reduce the risk of urinary tract infections (UTI). A review of studies published last year concluded that cranberry has a role to play in preventing recurring UTIs, especially in women over 45 who are more likely to get UTIs because of hormonal changes during and after menopause. (See Dec. 2019 Staying Healthy at www.sbh.com).

A new study(1) has found that cranberry can also help those who experience ‘dry’ overactive bladder, the condition that causes a person to have to urinate urgently and frequently but doesn’t cause incontinence. (For those with incontinence, the condition is referred to as ‘wet’ overactive bladder).

Researchers randomized women with symptoms of dry overactive bladder to receive 500 mg of dried cranberry powder or a placebo daily for a 6-month period.

Of the 60 women who finished the trial, those in the cranberry group experienced a 16% reduction in daily urination, a 57% reduction in daily urgency episodes compared to those symptoms at the study’s start. The participants taking cranberry also had a 40% decrease in how they perceived their bladder condition.

Compared with the placebo takers, the cranberry group urinated 1.91 fewer times daily and had 2.81 fewer daily urgency episodes.

According to the authors, the reduction in symptoms seen with cranberry compare favorably to the benefits reported for some prescription drugs (anti-muscarinics and beta-3 antagonists) used to treat overactive bladder. The researchers also called for larger and longer trials to confirm their findings.

It’s also important to know that while daily cranberry use may help prevent UTIs from recurring, cranberry is not effective in treating an active UTI which requires diagnosis and medication. So, don’t mistake UTI for overactive bladder.

The sudden and frequent urge to urinate is common in both overactive bladder and UTI, but the symptoms of the two conditions differ. UTI symptoms such as discomfort while urinating, are sudden while overactive bladder symptoms are ongoing.

Low Vitamin D Linked to Lower Urinary Tract Symptoms

A number of studies have linked insufficient levels of vitamin D in the body to lower urinary tract symptoms (LUTS), but the findings have been inconsistent. Researchers recently reviewed the studies to date to evaluate the LUTS and vitamin D relationship(2). LUTS symptoms include urinary urgency, frequency, incontinence, nocturia (waking up at night to urinate) and others. LUTS is fairly common in older men and women.

Including results from 23 studies with over 86,000 participants in the review and analysis, the investigators found that vitamin D deficiency raised the risk of LUTS two-fold. LUTS sufferers generally had lower vitamin D levels than those without the condition, suggesting that low vitamin D raises the risk for developing LUTS. Those who supplemented with vitamin D were also 11% less likely to have LUTS. the authors concluded that supplemental vitamin D shows promise in helping to alleviate LUTS symptoms.

Many tissues such as the prostate, the bladder wall, pelvic tissues and the urothelium (lining of lower urinary tract), are rich in vitamin D receptors. So, it’s not surprising that the vitamin could influence these tissues. It’s possible that vitamin D may be helping to quell chronic inflammation seen in benign prostatic hypertrophy (BPH) and/or affecting smooth muscle in the bladder.

References

1. Cho A, et al. Efficacy of daily intake of dried cranberry 500 mg in women with overactive bladder: A randomized, double-blind, placebo-controlled study. J Urol. Epub ahead of print Sept. 18, 2020.
2. Yuan P, et al. Systematic review and meta-analysis of the association between vitamin D status and lower urinary tract symptoms. J Urol. Epub ahead of print Nov. 18, 2020.

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In the news: Two Ways to Help Reduce Stress:Meditation & the Med Diet

Downside to Chronic Stress & Help to Tame It

We all know the downsides of too much stress: it can disrupt our sleep, interfere with work and relationships, and increase the risk of many chronic conditions such as heart disease and Alzheimer's.

According to the American Psychological Association, Americans report some of the highest perceived levels of stress worldwide – and that’s even before the pandemic and other stressful events of this past year.

So, what can we do to help tame the effects of chronic stress? In addition to strategies like physical activity and reducing triggers of stress, studies suggest that meditation and certain eating patterns can help ease stress too.

Mindfulness-Based Stress Reduction Helps Eyes

One meditation technique called mindfulness-based stress reduction is based on observing the breath by focusing attention on the natural relaxed flow of air going in and out of the body. A newly published study(1) tested this practice in glaucoma patients, and the results are worth highlighting.

In the study, glaucoma patients who were already being fully treated with topical medication but whose intraocular pressure (IOP) was still high, were assigned to 45 minutes daily of a mindfulness meditation program for 3 weeks while another group continued on medication alone.

At the end of 3 weeks, IOP had dropped significantly in the meditators compared to the non-meditators. Biochemical measures also indicated that the meditation actually exerted beneficial effects on eye tissues.

Last year a review(2) looked at mindfulness-based intervention studies and found that 79 of the 85 included trials reported significant positive effects on at least one health-related outcome. Most of the studies were focused on anxiety, depression, stress and cognitive outcomes. The studies all tested brief and less intense mindfulness-based interventions often used as self-management tools.

For those interested in exploring mindfulness meditation, it’s possible that your physician may have a referral. You can also try contacting an academic center, or local yoga center. Some universities – e.g. UCLA, UC San Diego, Brown University, and University of Massachusetts – have established mindfulness centers, some with online resources.

Go for the Mediterranean (Med) Diet?

According to investigators from Wake Forest Medical School, eating a Med diet(3)(4) may provide a relatively easy way to help lessen the physiological effects of stress and promote healthy aging.

A number of studies have linked a higher intake of fruits and veggies with lower perceived stress, but a new study examined the diet-stress relationship in a controlled way. Since the typical “Western” diet is rich in animal protein, saturated fat, salt and sugar, the researchers wanted to find out if that diet worsened the stress response compared to a Med diet, where much of the protein and fat come from plant sources.

Testing the stress response to the two diets in animals under chronic and acute stress conditions, they measured changes in the sympathetic and para-sympathetic nervous systems and in the stress hormone cortisol. High sympathetic nervous system activity can be harmful to health, so maintaining a healthy balance between the two systems is important.

Compared to the Western diet, those fed the Med diet showed enhanced stress resilience as reflected by lower sympathetic nervous system and cortisol responses to stress, and more rapid recovery after the stress ended. The Med diet also slowed the aging of the sympathetic nervous system as the animals aged.

References

1. Dada T, et al. Effect of mindfulness meditation on intraocular pressure and trabecular meshwork gene expression: A randomized controlled trial. Am J Ophthalmol. Epub Oct 22, 2020
2. Howarth A, et al. Effects of Brief Mindfulness-Based Interventions on Health-Related Outcomes: a Systematic Review. Mindfulness. 10:1957–1968, 2019.
3. Shively CA, et al. , Mediterranean diet, stress resilience, and aging in nonhuman primates. Neurobiol Stress, 13: 100254, 2020.
4. Wake Forest Baptist Medical Center. "Mediterranean diet helps reduce effects of stress in animal model." ScienceDaily, Nov. 16, 2020.

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In the news: Experts Advise on Nutrients & Immunity More Flavanols for Better Blood Pressure

Swiss Panel on Nutrients & Immune Function

An expert panel of Swiss physicians and professors in cooperation with the Swiss Society of Nutrition has published recommendations on Swiss and European nutrient needs for a well-functioning immune system with a special focus on viral infections(1).

The panel stresses the importance of following a well-balanced diet, but also points out that dietary changes are a long-term endeavor and therefore recommends a complement of supplemental nutrients. The panel’s guidance aims to help fill nutrient gaps, especially for those 65 and older. It includes:

Vitamin D

Vitamin C

DHA & EPA

Selenium

Zinc

More Flavanols For Better Blood Pressure

Flavanols, a type of flavonoid found grapes, red wine, tea and cocoa, have been shown to improve blood vessel function in intervention studies. In a new study(2), researchers looked at the relationship between flavanols and blood pressure in over 25,000 participants in a larger study. The new study was unique in that they measured biomarkers of the flavonoid in blood to indicate intake, a much more accurate measure.

Those with the highest intake (biomarker levels) had lower systolic blood pressure – levels comparable to what’s achieved by following a Mediterranean Diet or moderately reducing salt intake.

References

1. Berger M, et al. White paper on Nutritional status in supporting a well-functioning immune system for optimal health with a recommendation for Switzerland. Schweizerische Gesellschaft für Ernährung, Société Suisse de Nutrition, Società Svizzera di Nutrizione. 2020.
2. Ottaviani J, et al. Biomarker-estimated flavan-3-ol intake is associated with lower blood pressure in cross-sectional analysis in EPIC Norfolk. Sci Reports. Oct. 21, 2020.

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In the news: Vitamin C For Age-related Muscle Loss? Multis & Honey for Cold & Flu Season

Vitamin C May Help Maintain Muscle Mass

One of the challenges of growing older is a loss of muscle mass and strength. But according to a newly published study, higher intakes of vitamin C may help work against that trend, likely by protecting muscle cells from free radical damage. Vitamin C is also required for making collagen, a component of connective tissue and muscle, and for producing carnitine found in skeletal muscles that use fatty acids a source of fuel.

In the new study(1), researchers examined data from more than 13,000 participants of an earlier study, looking at their dietary intake of vitamin C, blood levels of the vitamin, and measures of skeletal muscle mass.

After taking into account other factors that could affect the results, they found that those consuming the highest amount of vitamin C or with the highest blood levels had the greatest skeletal muscle mass. These associations applied to those over and under 65 years.

They also observed that about 60% of men and about half the women were not meeting recommended intake levels of the vitamin. In addition to supplemental vitamin C, good sources of vitamin C include citrus fruits, tomatoes, potatoes, red and green peppers, kiwi, strawberries, Brussels sprouts and cantaloupe.

According to the study’s authors, their findings suggest that “getting sufficient dietary vitamin C may be useful for reducing age-related muscle loss.”

‘Multi’ Use May Lead to Less Severe Illness

A small but intriguing study(2) by researchers at Oregon State University, suggests that taking a multivitamin and mineral supplement (multi) may result in upper respiratory illness symptoms that are less severe and resolve more quickly in older adults.

Age-related decline in the immune system is common, and many vitamins and minerals play a role in immune function. Since about 35% of older adults in the US are deficient in one or more micronutrients – especially immune-bolstering vitamins C, D and zinc, researchers at Oregon State University examined whether healthy people would benefit from taking a multi. They hypothesized that supplementation would improve measures of immune function and status.

Forty-two adults aged 55-75 were assigned to a multi or placebo for 12 weeks, and immune indicators were measured. Participants took a brief daily survey (adapted from the Wisconsin Upper Respiratory Symptom Survey) to record any illness symptoms and rate symptom severity.

While the immune indicators were not altered in the multi group (none reached statistical significance), blood levels of vitamin C and zinc improved. In turn, these improvements were associated with a decline in illness. Those taking the multi averaged 3 days of illness vs. more than 6 days for the placebo group. Illness symptoms were significantly less severe in the multi group as well. The authors call for larger studies specifically designed to measure clinical outcomes.

Honey Quells Coughs and URTI Symptoms

Studies have reported that honey can calm upper respiratory tract infections (URTI) related coughing, especially in children. But a new review(3) of 14 studies asked whether honey could benefit other URTI symptoms, and work for adults as well as kids.

Bottom line, honey was most helpful for cough – less coughing and less severe coughing. But it also was better than ‘usual care’ for combined URTI symptoms. The authors note that while the methods of usual care varied among the studies, they were all “similarly ineffective.” They also point out that using honey might contribute to slowing antibiotic resistance. Antibiotics are over-prescribed for cold and flu even though they don’t work for viral infections.

References

1. Lewis LN, et al. Lower Dietary and Circulating Vitamin C in Middle- and Older-Aged Men and Women Are Associated with Lower Estimated Skeletal Muscle Mass. J Nutrition. Epub ahead of print Aug. 27, 2020.
2. Fantacone ML, et al. The effect of a multivitamin and mineral supplementation on immune function in healthy older adults: A Double-blind, randomized controlled trial. Nutrients. 12, 2447, 2020.
3. Abuelgasim H, et al. Effectiveness of honey for symptomatic relief in upper respiratory tract infections: a systematic review and meta-analysis. BMJ Evid Based Med. Epub Aug 18, 2020.

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In the news: Feel Better by Eating More Flavonoids; Magnesium Key for Good Vitamin D Levels

Polyphenols Improve Psychological Wellbeing

Fruits, vegetables, legumes (beans and peas), tea, wine, spices, chocolate and coffee are foods and beverages that offer abundant amounts of polyphenol plant compounds. Diets high in these compounds have been linked to lower risk of chronic diseases such as cardiovascular disease, diabetes, and cancer. Some intervention studies suggest that polyphenols support memory and brain function as well.

Researchers from Queen’s University in Belfast Ireland set out to examine whether a polyphenol-rich diet might also impact psychological well-being and mental outlook(1).

In the Polyphenol Intervention Trial, investigators assigned 99 participants with mild hypertension to eat either a low or a high polyphenol diet for 8 weeks after a 4-week washout period where minimal polyphenols were consumed.

Lifestyle and psychological well-being were assessed at the beginning and the end of the trial using a variety of validated questionnaires (e.g. Beck Depression Inventory-II, Rand Medical Outcomes short form).

Participants on the high-polyphenol diet (berries, vegetables and dark chocolate) had a significant decrease in depressive symptoms compared to those in the low-polyphenol group. The ‘high-poly’ group also showed a meaningful improvement in physical and mental health scores vs. the ‘low-poly’ participants.

An earlier finding from the same trial showed that the high poly diet enhanced the ability of blood vessels to dilate in these mildly hypertensive participants. This boost in vasodilatation might have also resulted in the newly reported improvements in mood. Other studies have reported changes in vessel structure and lower levels of the vasodilator nitric oxide in depressed patients.

The bottom line: Eating more foods rich in polyphenols could potentially lead to a more positive outlook and better general physical and mental health, at least in those with mildly high blood pressure.

Magnesium Key for Good Vitamin D Levels

Everyone recognizes the value of keeping adequate vitamin D levels for maintaining bone and a well-functioning immune system. But not everyone may realize the importance of magnesium in supporting optimal vitamin D blood levels.

Magnesium assists in the activation of vitamin D. In fact, all of the enzymes that metabolize vitamin D seem to require magnesium. So, the ability of vitamin D to become bioactive in the body is a process that depends on magnesium – a mineral that many Americans do not consume enough of in their diets.

University researchers in Granada Spain recently conducted a trial of magnesium supplementation in 52 post-menopausal women between 44 and 76 years of age to examine the influence of this mineral on vitamin D status(2).

The women were randomly assigned to receive 500 mg magnesium or placebo daily for 8 weeks. The investigators assessed dietary intake of various nutrients in the participants’ diets and measured vitamin D by two methods for accuracy.

A very high portion of the women were found to be vitamin D deficient at the study’s start – over 80%. Those that were taking magnesium had significantly increased vitamin D levels compared to the women getting placebo.

To pack more magnesium into your diet, include leafy green vegetables like spinach, nuts, whole grains, seeds and beans, fish (tuna is high), dairy, fruit (particularly avocados), and dark chocolate.

References

1. Kontogianni MD, et al. A high polyphenol diet improves psychological well-being: The Polyphenol Intervention Trial (PPhIT). Nutrients. 12, 2445, 2020.
2. Vázquez-Lorente H, et al. Response of Vitamin D after magnesium intervention in a postmenopausal population from the province of Granada, Spain. Nutrients. 12, 2283, 2020.

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In the news: Air Pollution, Omega-3s & the Brain; Riboflavin May Help Migraine in Children

Can Omega-3s Help Protect the Brain from Pollution?

A number of studies have connected air pollution to increased risk of lung and heart disease. Research also suggests that exposure to air pollution may affect the health of our brain as well.

The brain shrinks as we get older, including white matter – the tissue found deep in the brain. White matter contains nerve fibers that connect other parts of the brain and spinal cord, allowing us to think fast and walk straight for example.

The results of animal studies suggest that exposure to air pollution might have a pro-inflammatory effect on the brain, while omega-3 fatty acids may play a role in protecting the integrity of white matter structure.

A research team from Columbia University recently investigated whether consuming omega-3 fatty acids might help protect against the potential toxic effects of air pollution and preserve brain volume in older women(1).

The researchers looked at 1,315 dementia-free women aged 65 to 80 years who had participated in an earlier observational study and had undergone structural brain magnetic resonance imaging. Red blood cell content of EPA and DHA was measured as a marker reflecting omega-3 levels in other tissues.

After adjusting for other factors that could affect brain volume, the researchers found that participants with higher levels of EPA and DHA fatty acids in red blood cells had significantly greater volumes of white matter as well as in the hippocampus region of the brain

The results were also in agreement with the participants’ dietary intake of fish: higher consumption, less white matter shrinkage. The study suggests that even moderate dietary intake of 1-2 servings of fish weekly may help counteract the potential harmful effects of air pollution on the brain.

More research is needed to confirm this observation, but the results do offer insight into how a healthy diet might reduce the effects of air pollution on cognitive decline.

Childhood Migraine & Riboflavin (Vitamin B2)

Migraine headache is a common, and often disabling condition that causes painful headaches that can be accompanied by nausea and heightened sensitivity to light, sound, and smells. Though the causes of migraine aren't fully understood, genetics and environmental factors appear to play a role. For some, noise, alcohol, caffeine, certain foods, or stress can trigger a migraine attack.

Researchers think that an imbalance of neuro-transmitters, particularly serotonin might be an underlying factor in some migraine sufferers. Brain energy metabolism has also been found to be abnormal in migraine. This has prompted research into riboflavin,a B vitamin involved in mitochondrial function and energy production.

A recent review(2) of riboflavin and migraine studies concluded that the vitamin reduces the frequency of migraines in adults, though results in children and adolescents have been mixed. The rate of migraine diagnosed among younger groups is increasing, with 11% of those 5-15 years old and 28% of those 15-19 years old found to suffer from migraine. So, identifying safe and helpful ways to manage this condition is important.

A study presented at the 62nd Annual Scientific Meeting of the American Headache Society in June(3) reports that riboflavin reduced the frequency of headache in 62% of children and adolescents seen by pediatric headache specialists at the University of Texas at Austin. The vitamin also reduced the intensity and the duration of migraines. Children weighing 44-88 lbs. received 100 mg twice daily, while those weighing over 88 lbs. were given 200 mg twice a day.

The results of this study, though not yet published and not placebo controlled, are promising and warrant future research into riboflavin for pediatric migraine.

References

1. Chen C et al. Erythrocyte omega-3 index, ambient fine particle exposure and brain aging. Neurol. July, 2020.
2. Thompson DF and Saluja SH. Review article. Prophylaxis of migraine headaches with riboflavin: A systematic review. J Clin Pharm Ther. 42:394–403, 2017.
3. Practice Update. AHS 2020: Riboflavin reduces monthly headache days significantly in a majority of children and adolescents. June 15, 2020.

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In the news: Added Spices Help Curb Inflammation; Zinc: Who May Need More & Why?

Spice Blend Combats High Fat, Carb Meal

Adding an array of spices to your meal – if you like them – might be a way to make a high-fat or high-carb meal more healthful, according to the authors of a new study from Penn State (1), (2).

The findings might be particularly helpful for those who are trying to lose weight but haven’t quite made all the necessary changes to achieve their weight loss goals. These are also stressful times, when comfort foods like mac n’ cheese can be hard to resist.

Research has found that inflammation can spike after eating a meal high in fat or sugar. An overload of fat and carbs causes immune cells to react, produce more free radicals, and release inflammatory cytokines.

Whether or not this short-term inflammatory burst contributes to unhealthy chronic inflammation isn’t totally clear, but some evidence points in that direction. Chronic inflammation – common in over-weight and obesity – plays a central role in cancer, heart disease, diabetes and other diseases.

In the study, overweight or obese men 40-65 years old randomly consumed 3 versions of a high fat, high carb meal (coconut curry chicken with muffins and biscuits) on 3 different days: one meal with no spices, one with 2 grams (g) of spices, and one with 6 g of spices.

The researchers found that pro-inflammatory cytokines were reduced following the meal containing 6 g of spices compared to the meal containing 2 g of spices or no spices.

The spice blend consisted of basil, bay leaf, black pepper, cinnamon, coriander, cumin, ginger, oregano, parsley, red pepper, rosemary, thyme and turmeric. Six g of the spices roughly translates to between 1 teaspoon to 1 tablespoon depending on how the spices are dried, according to the study.

The authors will be working on further studies to determine the effects of spices over longer periods of time and within a more diverse population. In the meantime, spices make meals tastier and may help calm the high fat/carb post-meal surge in inflammation.

Zinc: Role in Immune Function

Zinc is vital to a well-functioning immune system. Severe zinc deficiency depresses immune function, and even mild to moderate degrees of zinc deficiency can impair macrophages and neutrophils, natural killer cell activity, and complement activity-- immune cells whose job it is to protect against the spread and movement of foreign invaders.

The body also requires zinc to develop and activate T-lymphocytes or “T cells”. T cells actively destroy infected cells and signal other immune cells to join in the immune response.

Research suggests that zinc also plays a role in controlling infections by helping to prevent out-of-control inflammation that can be damaging to the body.

Who May Be at Risk for Low Zinc Levels?

People who don’t get enough zinc in their diets. Strict vegetarians are one example. The bioavailability of zinc from vegetarian diets is lower due to not eating meat and seafood. Meat is high in bio-available zinc and may enhance zinc absorption. Vegetarians typically eat high levels of legumes and whole grains, which contain compounds (phytates) that bind zinc and interfere with its absorption.

People who have absorption problems and chronic diseases. People with Crohn’s disease and ulcerative colitis, for instance have decreased absorption of zinc. Examples of chronic disease associated with low zinc include malabsorption syndrome, chronic liver disease, chronic kidney disease, sickle cell disease, diabetes (especially with diabetic complications), and alcoholism.

Elderly. Low zinc blood levels are not uncommon in older individuals, due in part to poor dietary intake, less efficient absorption and other factors in the aging process.

References

1. Oh ES, et al. Spices in a high-saturated-fat, high-carbo-hydrate meal reduces postprandial proinflammatory cytokine secretion in men with overweight or obesity. J Nutr. May, 2020
2. Penn State News. Adding a blend of spices to a meal may help lower inflammation. May 21, 2020.
3. Wessels I, et al. Zinc as a Gatekeeper of Immune Function. Nutrients. 9:1286, 2017.

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In the news: If You Have AMD, Does What You Eat Matter? Flavonoids May Lower Alzheimer’s Risk

If you’re been thinking more about eating healthfully, several new studies might inspire you to transition to the Mediterranean (Med) diet. New research links the diet to ocular benefits. And if the fruits & veggies in the diet are packed with flavonoids, brain benefits too.

Following Med Diet May Slow Late-AMD Risk

If you’re being treated for age-related macular degeneration (AMD) and taking an AREDS2 supple-ment too, does what you eat make any difference to how the disease develops? The results of two new studies suggest that sticking to the Med diet matters.

In the first study (1), researchers looked at participants in the AREDS and AREDS2 clinical trials to see whether more closely following the Med diet affects the risk of the disease progressing to late stage AMD, either geographic atrophy (dry AMD) or neo-vascular disease (wet AMD).

Comparing the highest adherence to Med diet vs. the least showed a 22% reduction in relative risk for late AMD, a 29% reduction for dry AMD, and a 16% reduction for wet AMD. Consuming more fish
contributed to the diet’s protective effect, and the benefits were more pronounced in people who carried certain AMD-protective genes.

The second study (2) asked whether genetics and sticking with the Med diet could affect the growth and size of drusen in AREDS participants. Drusen are the yellow deposits found under the retina that increase the risk of developing AMD and, as the drusen grow larger, the risk of progressing to later stages of AMD.

The study found that inherited susceptibility to AMD was linked with drusen growth. But it also revealed that sticking more closely to a Med-style diet (fruits, veggies, legumes and fish), may lower the risk of drusen enlarging. While we can’t change the genetic hand we’re dealt, we can aim for a healthy diet.

Apples, Berries, & Tea May Curb Alzheimer’s

An observational study from Tufts University helps affirm a protective link between flavonoids and Alzheimer’s Disease plus other related dementias (3).

Most studies looking at links between foods and dementias have been short term. But dementias and Alzheimer’s don’t happen overnight – they develop over time. Microscopic changes in the brain begin long before the first signs of memory loss in Alzheimer’s, and blood vessel damage starts long before the problems of vascular dementia surface.

The new research looked at dementia risk and flavonoid intake over a 20-year period. Flavonoids are thought to help protect nerve cells and combat neuro-inflammation.

The study followed 2800 people in their 50s and free from dementias, updating their flavonoid intake about every five years. After adjusting for factors that affect the risk for dementia, the researchers found that low vs. high intake of 3 types of flavonoids was linked to higher dementia risk as follows:

• about 2x the risk for low vs. high intake of flavonols (apples, pears, tea);
• roughly 2x the risk for low vs. high intake of flavonoid polymers (pears, apples, tea);
• about 4 x the risk for low vs. high intake of anthocyanins (blueberries, strawberries, red wine);

The results were similar for Alzheimer’s. Examples of “high” intakes in the study were 8 apples and pears monthly (flavonols); for anthocyanins, 71/2 cups per month of blueberries or strawberries; and about 19 cups of tea monthly (flavonoid polymers).

References

1. Keenan TD, et al. Adherence to the Mediterranean diet and progression to late age-related macular degeneration in the Age-Related Eye Disease Studies 1 and 2. Ophthalmol. Epub ahead of print April 26, 2020
2. Merle BMJ, et al. Genetic susceptibility, diet quality, and two-step progression in drusen size. Invest Ophthalmol Vis Sci, 61:17, 2020. 
3. Shishtar E, et al. Long-term dietary flavonoid intake and risk of Alzheimer disease and related dementias in the Framingham Offspring Cohort. Am J Clin Nutr. 00:1–11, 2020. Open Access.

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In the news: Building Resilience: Move, Keep Calm & Eat Well for Immune Health

We are all doing our best to practice core behaviors that can help in the fight against Covid-19: washing hands frequently and trying not to touch our face, coughing or sneezing into tissues, and staying home, practicing social distancing, and wearing masks when directed. (As of this writing, many of us remain under stay-at-home directives).

Another thing we can do is work at building physical and mental resilience, and a good place to start is focusing on the inter-related actions that help maintain a well-functioning immune system.

What: Prioritize some form of daily exercise
Why: Regular, moderate exercise can play an important part in supporting a healthy immune system1. It improves defense activity, causing changes in white blood cells that fight disease. Evidence suggests that it likely helps delay age-related immune dysfunction in older individuals. Moderate exercise, for example, has been found to enhance the response to flu vaccination in elderly men2.
How: There may be no access to gyms and health clubs – and limited access to the outdoors for some – but there are still opportunities to exercise in isolation. Daily walks in the neighborhood may be possible (taking recommended precautions), and there are many online opportunities for participating remotely in exercise classes, including the gentle form of exercise, tai chi. Be creative – Mayo Clinical has some advice: https://www.youtube.com/watch?v=p9Dw-4ycMQQagraph

What: Manage Stress and Loneliness
Why: Stress and anxiety can reduce the immune system’s ability to fight off foreign invaders. The stress hormone corticosteroid can suppress the effectiveness of the immune system by lowering the number of lymphocytes, key immune cells. Loneliness leads to increased stress, which triggers the axis of hormones that can raise blood pressure and impact sleep.
How: We’re all facing uncertainty which can generate stress, and isolation which can be especially difficult for those who live alone. A few tips for countering stress: 1. Exercise is a potent stress-reducer. 2. Try deep breathing for a few minutes several times daily: breathe in slowly through the nose for a count of four, and exhale slowly counting to four. 3. Avoid looking at the news first thing in the morning to set a calmer tone for the day, and the last thing at night for better sleep. 4. Reach out to at least one person daily – by phone, text, social media or whatever online platforms are available to you – and listen. If appropriate, express your own concerns and emotions.

What: Eat as healthfully as possible
Why: What we eat plays a fundamental role in how we feel and in keeping the immune system healthy. While there is interest in taking botanicals for which there is some evidence of immune support such as Echinacea, Elderberry or Andrographis, any specific effects of the herbs on novel virus activity in humans is unknown. So, start with the basics: a well-rounded diet that provides the many vitamins and minerals that work in harmony to support a robust immune system3. Brightly colored fruits and veggies are key contributors for many of those nutrients, while seafood is a source of mood-supporting omega-3 fatty acids and zinc which is vital for immune T-cell function.

Vitamins A (meat or vegetables such as carrots, sweet potato), D (fortified dairy) and vitamin C (citrus, peppers) deserve special mention. Vitamin A plays a role in supporting mucosal immunoglobulin A (IgA)—the first line of immune defense against invaders. Vitamin D helps keep the immune system balanced, and low levels (common in the US) are associated with frequent colds and flu. Vitamin C, whose levels drop with infection, calls the immune troops (natural killer cells, interferons, T-cells) into action.
How: With the challenges of getting out to shop and grocery shelves often poorly stocked, you can choose frozen fruits and vegetables if fresh produce is scarce. Canned tuna, salmon and sardines are an alternative should fresh seafood be unavailable. Yogurt and fermented foods are also a good choice as both support healthy gut bacteria – important because the gut and lung biomes are connected4. Finally, it makes good sense to take a comprehensive multi-nutrient supplement to ensure good supplies of vitamins, minerals and phytonutrients.

References

1. Nieman D and Wentz L The compelling link between physical activity and the body's defense system. J Sports Hlth Sci. 8:201-17, 2019.
2. Elderly men with moderate and intense training lifestyle present sustained higher antibody responses to influenza vaccine. Age (Dordr). 37(6): 105, 2015.
3. Gombart A, et al. A Review of Micronutrients and the Immune System–Working in harmony to reduce the risk of Infection. Nutrients. 12:236, 2020.
4. Anand S and Mande S. Diet, Microbiota and Gut-Lung Connection. Front Microbiol. 9: 2147, 2018.

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In the news: Cocoa for People with PAD; Vinegar Pre-Treatment for Safer Grilling

Cocoa May Help PAD Patients Walk Further

Researchers from Northwestern University report that drinking a bioflavonoid-rich cocoa beverage daily improved walking distance, blood flow to the calves and some measures of muscle function in a study of patients with peripheral artery disease or PAD. The study was published in Circulation Research, a journal of the American Heart Association.

PAD, which affects about 10% of the American pop-ulation, is a circulatory problem in which narrowed arteries reduce blood flow to the limbs, most frequently the legs. While some people with PAD have no symptoms, others experience pain, numbness, or heaviness in their leg muscles when walking or climbing stairs. Pain when walking means that the legs aren’t receiving enough blood flow to keep up with the increased demand of physical activity.

Research has also identified impaired vessel wall function, poor blood flow in tiny vessels like arterioles and capillaries, poor mitochondrial function and altered skeletal muscle structure in patients with PAD (1).

In the present study (2), 44 older participants with PAD were randomly assigned to take placebo or 15 g of cocoa providing 75 mg of the bioflavonoid epicatechin daily for 6 months. The total amount of cocoa was divided into three beverage servings daily. Studies point to epicatechin, a member of the flavanol class of bioflavonoids, as the compound largely responsible for cocoa and dark chocolate’s ability to dilate blood vessels.

Compared to the placebo group, those consuming cocoa were able to walk 43 meters (141 feet) farther in the 6-minute walking test conducted 2 ½ hours after drinking the cocoa beverage. Consistent with other studies, 6-minute walking distance declined for those in the placebo group over time.

At the 6-month mark, participants receiving the cocoa flavanols also had better blood flow to calf muscles and increased capillary density. In addition, the group showed greater activity in calf muscle mitochondria – the energy producing structures inside cells.

This study was small, and its findings of improved walking distance and better muscle health need to be replicated in larger trials. If the benefits of cocoa are confirmed it would be clinically meaningful since few medical therapies can improve the 6-minute walk test or prevent decline in those with PAD.

It’s possible that people with PAD may get a prescription to eat more dark chocolate in the future! The cocoa used in the study is available as unsweetened cocoa powder which is present in dark chocolate (85% or more cacao) compared with milk chocolate.

A Strategy for More Safely Grilling Meats

While it’s still too early in the season to think about charcoal grilling, a new study (3) has found an easy-to-apply strategy to making charcoal-grilled meats a little safer.

University researchers in Portugal investigated the effect of applying five different vinegars as seasoning on the formation of polycyclic aromatic hydrocarbons (PAHs) in charcoal-grilled pork loin. PAHs are chemicals that occur naturally in coal (and other sources), and high temperature cooking forms PAHs in meat and other foods. Many PAHs are believed to be carcinogenic.

The researchers found that spraying the meat with vinegar prior to grilling significantly inhibited or prevented PAH formation. Elderberry vinegar was most efficient (82% inhibition), followed by white vinegar (79%), red wine and cider vinegars (66%), and raspberry vinegar (55%).

References

1. Matsui R and Hamburg N. Editorial: Eating chocolate to improve muscle health and walking ability in patients with peripheral artery disease. Circ Res, 126:600-602.
2. McDermott MM, et al. Cocoa to improve walking performance in older people with peripheral artery disease. The COCOA-PAD Pilot Randomized Clinical Trial. Circ Res. 126:589–99, 2020.
3. Cordeiro T, et al. Inhibitory effect of vinegars on the formation of polycyclic aromatic hydrocarbons in charcoal-grilled pork. Meat Sci. Epub Feb. 5, 2020.

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In the news: Women 50+: Lose Weight to Cut Breast Cancer Risk;
The Latest on Intermittent Fasting

Shedding Weight May Lower Breast Cancer Risk

Though being overweight or obese (a high body mass index or BMI) is an established risk factor for breast cancer in postmenopausal women, researchers have wrestled with the important question of whether losing excess weight can reverse that risk. The problem has been a lack of sufficient evidence.

Now, a new analysis (1 )of over 180,000 women from 10 prospective studies – large enough to have statistical accuracy – has shed light on that question: Can losing weight, and keeping it off, favorably impact breast cancer risk?

It appears that for women overweight and over 50, shedding weight and maintaining that loss lowers the risk of breast cancer, at least for those not on hormone therapy. And the greater the amount of maintained weight loss, the lower the risk, though even fairly modest amounts of weight loss can be of benefit. The study was published in the December issue of the Journal of the National Cancer Institute.

Researchers from the American Cancer Society, Harvard and others report that women (not using postmenopausal hormones) who sustained a loss of roughly 4.4-10 pounds had an 18% reduction in risk compared to women whose weight remained stable over about 10 years. Stable weight was defined as consistently staying within plus or minus 4.4 pounds.

Sustained weight loss of 10-20 pounds lowered the risk by 25%. Losing and keeping off 20 pounds or more decreased the risk by 32%.

Even women who lost 20 or more pounds but gained some (but not all of it) back, still lowered their risk of this cancer compared to women with stable weight.

According to the authors, the results suggest that even modest weight loss is associated with lower breast cancer risk for women 50 and older. “Breast cancer prevention may be a strong weight loss motivator for the two-thirds of American women who are overweight or obese”, they said.

What is Intermittent Fasting?

Intermittent fasting (IF) is following a dietary pattern that cycles between periods of eating and fasting. It doesn’t tell you what foods to eat, but rather when you should eat. There are different IF approaches, but most split the day or week into eating and fasting periods.

Many animal and clinical studies of time-restricted eating have shown that changing back and forth between eating and fasting triggers a metabolic switch to go from storing fat to converting fat into energy. The body switches from using glucose derived from the liver to ketones derived from fat cells. IF aids weight loss and promotes other health benefits too – perhaps even longer life.

What is the Evidence for IF Benefits?

A recent paper published in the New England Journal of Medicine reviews the effects of IF on health, aging and disease (2). The report, according to the authors, is meant to serve as a road map for doctors to guide patients who want to try IF. The review focuses on two patterns: eating between a 6-8-hour period daily and fasting the remaining16-18 hours (time-restricted eating), and fasting for two days out of the week.

The authors point to pre-clinical studies and clinical trials that suggest IF has benefits for many health conditions including obesity, heart disease, neurologic conditions and type 2 diabetes. In animals, IF improves the health span and also increases lifespan, similar to some findings of calorie restriction studies. But one problem is that trials in humans are mostly short-term, so it’s not yet known whether people can stick with IF over the long haul to gain the same longevity benefits.

Is IF for Everyone?

Probably not, since eating 3 meals daily is culturally ingrained, and some people may not be able to adhere to IF. Additionally, others with health problems should check with their physicians first for guidance. But for many, IF is a promising way of eating for health.

References

1. Teras LR, et al. Sustained weight loss and risk of breast cancer in women > 50 years: a pooled analysis of prospective data. JNCI. Epub ahead of print, Dec. 13, 2019.
2. de Cabo R and Mattson MP. Effects of intermittent fasting on health, aging, and disease. NEJM. 381:2541-51, 2019.

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Cruciferous Veggies Might Fight Fatty Liver
Health-Promoting Walnuts

Veggie Compound May Help Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) is a common condition where excess fat accumulates in the liver of those who drink little or no alcohol. NAFLD has, in fact, become a global epidemic. Leading risk factors for fatty liver include:obesity/overweight, type 2 diabetes, high cholesterol or having had gastric by-pass surgery.

Although it rarely causes symptoms, the condition has gained attention because, over time, NAFLD can lead to serious problems: liver damage and increased risk for liver cancer. Obesity can trigger inflammation and worsen liver damage in those with liver disease.

Shedding excess weight and eating healthfully is one reliable way to combat fatty liver. In addition, a new study (1) suggests that compounds found in cruciferous vegetables might be helpful in fighting NAFLD.

Cruciferous veggies include Brussels sprouts, broccoli, cauliflower, kale, cabbage, and bok choy. These Crucifers are rich in indole – a compound that’s also produced by a variety of bacteria residing in our gut.

In a new, multi-level study, researchers from Texas A&M aimed to understand whether indole impacts fatty liver – and how it might do so – by investigating indole’s effects in people, animal models and individual cells.

The investigators looked at circulating levels of indole in 137 subjects and found lower levels in those with higher body mass index (BMI). Indole levels in people who were clinically obese were significantly lower than in lean individuals. Importantly, the team saw higher amounts of fat in the livers of obese people with lower levels of indole.

In experiments with mice fed high-fat diets to promote NAFLD, treatment with indole led to significantly less inflammation and fat accumulation in the liver.

The researchers also examined how indole affects individual cells. Adding indole to cultured cells resulted in the expression of a gene that regulates glucose breakdown, and stifled activation of pro-inflammatory immune cells (macrophages).

Shannon Glaser, PhD, professor, Texas A&M Health Science Center, said that in addition to reducing the amount of fat in liver cells, indole also acts on cells in the intestine, which send out signals that dampen inflammation (2). In future research, the team hopes to examine what healthy foods can alter gut microbiota and increase indole production in the future.

New Research Findings on Walnuts

While all nuts are welcome additions to a low saturated fat diet, walnuts with their high antioxidant and healthy fat content are one of the healthiest choices. Results from two new studies suggest that walnuts promote healthy gut bacteria and are linked to slower cognitive decline in at risk older people.

In the first study (3), Penn State researchers randomly assigned overweight participants to diets that replaced some of the saturated fat from a typical American diet with walnuts; or with vegetable oils (omega-3 alpha linolenic acid, the mono-unsaturate oleic acid).

The walnut group showed increases in gut bacteria that have been linked to improvements in some cardiovascular disease risk factors. Increases in the species Eubacterium eligens was associated with lower blood pressure measurements.

Researchers from Spain and California teamed in the second study (4) to see whether including 1-2 oz. walnuts in the daily diet of the elderly for 2 years could affect cognitive decline vs. a group that did not consume the nuts. While walnuts had little effect on cognition in the group overall, testing (fMRI) and further analysis suggest that walnuts might delay cognitive decline in those at higher risk – those who had lower initial cognitive test scores and who had smoked more

References

1. Linqiang M, et al. Indole alleviates diet-induced hepatic steatosis and inflammation in a manner involving myeloid cell PFKFB3. Hepatol. Epub ahead of print, Jan. 17, 2020.
2. Texas A&M AgriLife Communications. Natural compound in vegetables helps fight fatty liver disease. Feb. 6, 2020.
3. Tindall AM, et al. Walnuts and vegetable oils containing oleic acid differentially affect the gut microbiota and associations with cardiovascular risk factors: follow-up of a randomized, controlled, feeding trial in adults at risk for cardiovascular disease. J Nutr.
4. Sala-Villa A, et al. Effect of a 2-year diet intervention with walnuts on cognitive decline. The Walnuts And Healthy Aging (WAHA) study: a randomized controlled trial. Am J Clin Nutr Epub ahead of print, Jan. 7, 2020.

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In the news: Drink Up! New findings on coffee & Tea Health Benefits

New Findings on Health Benefits of Coffee & Tea

Coffee and tea are two of the most commonly consumed beverages worldwide. Both have been extensively studied for their potential health benefits, which are largely attributed to their high levels of antioxidant and anti-inflammatory compounds.

Regularly drinking coffee and/or tea has been linked to a lower risk of type 2 diabetes, heart disease and stroke, certain cancers, liver disease, and even gallstones. Several recent studies lend support to some of these benefits or help explain how they may work on a cellular level.

Tea May Cut the Risk of Stroke

Chinese researchers explored the relationship between tea consumption and stroke risk in a large- scale study of nearly ½ million men and women (1).

Overall, about 26% of participants reported drinking tea most every day, predominantly green tea. Among those who drank tea daily, drinking higher amounts and consuming it over longer periods of time were associated with greater risk reduction.

In short, this study in Chinese adults found that higher intake of tea, especially green tea, was associated with a lower risk of both types of stroke – ischemic (the type caused by a blocked vessel supplying blood to the brain) and hemorrhagic (caused by a leaking or ruptured artery in the brain).

Coffee May Cut Liver Cancer Risk in Half 

Researchers in the UK set out to see whether coffee consumption – and the type of coffee consumed – impacts the risk of digestive cancers by following 471,779 participants for 7 ½ years.

The research team reports that compared to non-coffee drinkers, those that consume coffee had a 50% lower risk of developing hepatocellular carcinoma, the most common form of liver cancer. The type of coffee the participants drank didn’t seem to make a big difference: the reduction in risk was similar for instant coffee (49%) and ground regular coffee (53%), with decaf reducing risk by 41%.

According to the researchers (2), their findings are consistent with the World Cancer Research Fund's report, which concluded that there is 'probable' evidence that coffee drinking lowers the risk of liver cancer. The researchers also investigated other digestive cancers, e.g. bowel and stomach, but found no consistent links with coffee drinking.

Shedding Light on How Coffee May Work

A 4-week controlled study (3) looking at drinking 2 cups of dark roast coffee daily vs. no coffee or tea found that coffee drinking reduced DNA damage – a finding shown in previous studies as well. Unrepaired DNA damage in some cells can increase the risk of cancer.

Preliminary research from Baylor University suggests that higher coffee intake may also foster a healthier gut microflora, which in turn, could impact health (4). Though it couldn’t be determined if caffeine, polyphenols, or both were responsible, coffee drinkers were found to have a richer array of gut microflora, more anti-inflammatory bacteria and lower levels of potentially harmful bacteria.

Regular vs. Decaf Coffee and Tea

Some of us go for the mental alertness boost provided by the caffeine these beverages contain. But others who are sensitive to the effects of caffeine (suffering anxiety, irritability or insomnia) should still be able to enjoy the many health benefits of these beverages. Decaf coffee contains the same healthful polyphenols, including chlorogenic acid and lignans that caffeinated coffee does. Teas come from the Camellia sinensis plant, which is used to make all tea varieties like green, oolong and black teas. Though some of the polyphenols and antioxidants are lost in decaffeination, studies indicate that these compounds are still present at levels sufficient to offer potential health benefits.

References

1. Tian T, et al. Tea consumption and risk of stroke in Chinese adults: a prospective cohort study of 0.5 million men and women. Am J Clin Nutr. Epub Nov. 11, 2019.
2. Tran KT, et al. Coffee consumption by type and risk of digestive cancer: a large prospective cohort study. Br J Cancer. 120:1059-1066, May 2019.
3. Schipp D, et al. Consumption of a dark roast coffee blend reduces DNA damage in humans: results from a 4-week randomized controlled study. Eur J Nutr. 58:3199-206, 2019.
4. Jiao L, et al. Presented at American College of Gastroenterology Annual Scientific Meeting, San Antonio Tx, Oct 28-30, 2019.

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In the news: Health Benefits of Cranberry

New Studies on Health Benefits of Cranberry

If you’re like most Americans, cranberry sauce is a staple on your menu for Thanksgiving dinner. But the potential health benefits of this little red berry native to North America extend throughout the year. Cranberry, for example may help women and children prevent urinary tract infections (UTIs) and help type 2 diabetics in controlling blood sugar levels.

Although antibiotics are without a doubt one of the greatest advances in medicine, their widespread use has led to resistant bacteria that are harder to treat. Pneumonia and many urinary tract infections (UTIs) are now among the common drug-resistant infections. Not only have scientists been trying to develop new antibiotics, there is also great research interest in finding strategies to help prevent some of these infections in the first place.

Current clinical evidence clearly indicates a possible benefit overall from the use of cranberries against UTIs. Consuming cranberries seems to prevent bacteria from attaching to the epithelial cells lining the urinary tract, for example. But the effectiveness of cranberry in certain segments of the population at increased risk for UTIs has been questioned.

A new review of cranberry (1) concludes that cranberry has a role in preventing recurring UTIs in women over 45. Older and midlife women are more likely to get UTIs because of the changing hormonal environment during and after menopause. The review looked at studies on the prevention of UTIs and assessed the efficacy and safety of various non-antibiotic strategies such as vitamin C, d-mannose, lactobacilli and estrogens.

The reviewers found evidence to support use of estrogens in postmenopausal women, and cranberry capsules in women aged 45 and older for the prevention of UTIs. Keep in mind that along with good hygiene practices, drinking plenty of water is also key to flushing bacteria out of the bladder and urinary tract.

Adults aren’t the only group concerned with UTIs. Kids can contract UTIs as well. In fact, UTIs are very common during childhood and about 10% to 30% of children experience recurrent UTIs after their first infection. Until recently, antibiotic prophylaxis was often recommended for children with recurrent UTI.

Pediatric researchers in Greece explored the efficacy and safety of cranberry capsules in children aged 2-14 with a history of recurrent UTIs2. Compared to the control group, children taking cranberry had a lower percentage of UTIs, experienced less days on antibiotics, and fewer of them required antimicrobial drugs to prevent recurrent infections. The authors suggest that standardized cranberry extract be considered in some children with recurrent UTIs as an alternative prevention method and one that helps avoid prolonged antibiotic treatment.

Cranberry, Blueberry & Type 2 Diabetes

Preclinical and clinical studies have suggested that cranberries as well as blueberries can also be helpful for diabetics in managing blood sugar levels. A recent review of 7 trials was carried out by university researchers in Brazil (3).

The investigators point out that many dosage forms were used in the clinical studies – juice, whole berries, dried berries and extracts, and highlight the results of several studies.

Daily cranberry juice (240 mL or an 8oz. glass) consumption for 12 weeks and blueberry extract or powder supplementation (containing 9.1 to 9.8 mg of anthocyanins, respectively) for 8 to 12 weeks showed a beneficial effect on glucose control in type 2 diabetic patients. Those results indicate a promising use of these berries in managing type 2, although more studies are required to better understand the mechanisms involved.

References

1. Gill CM, et al. A review of nonantibiotic agents to prevent urinary tract infections in older women. J Am Med Dir Assoc S1525-8610(19)30379-2 published online June 18, 2019.
2. Dotis J, et al. Cranberry standardized capsules may prevent recurrences of urinary tract infections in children. Clin Pediatri. 1: 1007, 2018
3. Rocha DMUP, et al. Effects of blueberry and cranberry consumption on type 2 diabetes glycemic control: A Systematic Review. Crit Rev Food Sci Nutr. 59:1816-28, 2019.

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In the news: Avocados Help Fend Off Harmful LDL; Positive Outlook for Better Heart Health

An Avocado-a-Day Helps Keep the Dr. Away?

A 2017 study from Tuft’s University found that eating an avocado daily could raise levels of macular pigment density in the eye, and that those increases were also related to some measures of better cognitive function. [See Staying Healthy archives, Nov. 2017 issue: www.sbh.com].

While avocados are only a rather modest source of the key macular pigment lutein, it’s thought that the mono-unsaturated fats in avocados enhance lutein’s absorption.

Now, new findings from Penn State researchers suggest that an avocado a day may help keep “bad” cholesterol levels down, at least in those overweight and obese (1).

In the study, 45 participants consumed in random order three different diets for five weeks: low fat, moderate fat, and moderate fat that incorporated one avocado daily.

Consuming the moderate fat + avocado diet lowered levels of small dense LDL particles. Small dense LDL is a subclass of LDL that is particularly susceptible to oxidation and is involved in the formation of artery plaque. This type of LDL is especially common in the blood of atherosclerosis patients.

Specifically, levels of oxidized LDL were lower after the avocado diet than before the study, and lower than after consuming the low fat or moderate fat diets. The avocado diet also raised blood levels of lutein, which can act as an antioxidant.

Eating more avocados may promote healthy arteries as well as support eye and brain health. Try Including avocados in your salad, go for the guacamole, or try them in scrambled eggs for breakfast.

Embrace Optimism for Heart Health

Whether you view the glass as half full or half empty may have a bearing on your risk of future cardio-vascular problems.

To learn more about the association between a positive mindset and the risk for future cardiovascular events and all-cause mortality, researchers conducted a meta-analysis of 15 studies that included nearly 230,000 individuals who were followed for an average of over 13 years (2).

They found that optimism was significantly associated with a 35% lower risk of cardiovascular events and a 14% lower risk of all-cause mortality. These findings suggest that optimism is associated with cardio-vascular benefits and that pessimism is associated with cardiovascular risk.

Since a positive outlook appears to be important for preventive health, what are some things we can do to adopt a more optimistic outlook?

Keep physically active and eat well. It goes without saying that physical activity and a healthy diet can impact cardio health by lowering blood pressure and blood lipids and increasing insulin sensitivity. But both have also been shown to buoy mood, tamp down depression and improve outlook.

Make a conscious effort to be positive. Challenging negative thinking and making a conscious effort to embrace the positive can train the brain to think more positively. Positive emotions can be contagious, so spending more time with optimistic friends and less with negative thinkers is helpful. Accepting what one can and cannot control also helps focus the mind on positive next steps instead of dwelling on the negative.

Meditate. Turn off the news and meditate. Even just 10 minutes of meditation daily has been shown to improve mood, decrease stress and improve sleep. Simple things like smiling more, taking a walk in nature and listening to music can also lift mood and dispel anxiety.

References

1. Wang L, et al. A moderate-fat diet with one avocado per day increases plasma antioxidants and decreases the oxidation of small, dense LDL in adults with overweight and obesity: Randomized controlled trial. J Nutr. Epub Oct, 2019.
2. Rozanski A, et al. Association of optimism with cardiovascular events and all-cause mortality: A systematic review and meta-analysis. JAMA Network Open. E1912200, 2019.

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In the news: Shingles of the eye on Upswing;Vinegar May Lower Blood Sugar; Curcumin: Mood & Working Memory

Increasing Cases of Shingles in the Eye

If you’re 60 or older and had chickenpox as a child, chances are you might experience shingles during your lifetime. After recovering from chickenpox (varicella zoster virus), the virus can hide in nerve cells, only to reappear later in life to cause shingles. About 1 in 3 will develop shingles, according to the Centers for Disease Control, often manifesting as a painful rash on the face or body.

The varicella virus can also reactivate in the nerves of the eye causing herpes zoster ophthalmicus or herpes of the eye. This occurs in about 20%% of people with shingles and shows up as a rash in and around the eye. Shingles in the eye can cause scarring, vision loss, and appears to increase the risk of stroke as well.

A 2019 study found that the incidence of shingles of the eye had tripled in the US from 2004-2016. The risk for shingles is greater with age and is more common in Caucasians than African Americans, Asians and Latino adults. Yet the study’s findings held even when they adjusted for age, sex and race. As a recent article on this topic in points out, diseases don’t usually double or triple over a 12-year period (1).

There are theories to explain the steady rise in cases of shingles of the eye. Fewer adults are getting an immune boost from exposure to kids with chicken pox, for example. Or more people have a suppressed immune system due to cancer chemotherapy, HIV/AIDS, treatment for autoimmune diseases or diabetes.

But one of the central causes is that people don’t seem to be taking advantage of the vaccines available to help prevent it. There are two vaccines approved for shingles: Zostavax and the more recent Shingrix, which requires two doses but is more effective. It’s unlikely that primary care doctors see many severe cases (neurologists, pain management specialists and ophthalmologists do), so they may not realize the full importance of preventing the condition. The vaccines are more commonly carried in retail pharmacies than in doctor’s offices. So, it may pay to ask your pharmacist as well as your health care professional whether you’re a candidate for a shingles vaccine.

Curcumin Reported to Support Cognition

In 2015, Australian researchers examined the effects of enhanced-bioavailability turmeric extract (400 mg daily Longvida brand, containing 80 mg curcumin) on cognitive function in 60 healthy older adults over 4-weeks. The investigators reported improvements in measures for memory, attention, fatigue, stress, and mood for turmeric when compared to placebo.   In a slightly larger and longer follow-up study (2), the same research team explored similar measures in 80 older people taking 400 mg Longvida or placebo daily for 12 weeks. While the study is not yet formally published, the reported findings appear to be consistent with those of the earlier investigation.

Compared to placebo, subjects taking curcumin experienced decreased tension, anger, confusion, and total mood disturbance at 4 weeks, with lower fatigue scores at both 4 and 12 weeks. They also experienced improvements in some aspects of working memory, the ability to remember and use relevant information while in the middle of an activity.

Apple Vinegar May Benefit Blood Sugar Levels

Emerging research suggests that apple cider vinegar, a source of acetic acid and polyphenols, may have some benefit in the management of type 2 diabetes. In the current study (3), 70 patients with type 2 and elevated lipids were assigned to receive 2 tsp. apple vinegar in water twice daily with meals, or to a control group.

The vinegar group showed improvements in fasting blood sugar and a measure of total antioxidant capacity vs. controls. Some of the participants were already taking anti-diabetes and/or lipid lowering meds, If you take anti-diabetic meds, check with your physician if trying vinegar so that blood glucose levels can be monitored.

References

1. Voelker R. Increasing cases of shingles in the eye raise key questions. JAMA. Epub August 7, 2019.
2. Scholey A, et al. A highly bioavailable curcumin extract improves neurocognitive function and mood in healthy older people: A 12-Week randomized, double-blind, placebo-controlled trial. Cur Develop Nutr. 3:S1, June, 2019.
3. Gheflati A, et al. The effect of apple vinegar consumption on glycemic indices, blood pressure, oxidative stress, and homocysteine in patients with type 2 diabetes and dyslipidemia. Clin Nutr ESPEN Epub July 9, 2019.

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In the news: Meal Timing May Hold Health Benefits; Busting the Myth of 10,000 Steps Daily

Dinner at 2:00? Timing of Meals May Matter

A study from University of Alabama researchers first reported in 2016 that coordinating meals with the body’s internal clock seems to be a good strategy for reducing appetite. The researchers think this strategy might be helpful for losing weight or maintaining their weight. (See Staying Healthy, Dec. 2016, www.sbh.com).

Called “early time-restricted feeding”, the idea is to eat 3 meals daily but keep food intake within a shorter daily timeframe to better align with metabolic activities that function more optimally in the morning. 

In the study, overweight participants tried two different meal timing plans: eating meals between 8 a.m. and 2 p.m., then switching to eating meals with same number of calories but over the more traditional time span of 8:am through 8 p.m.

The early eating pattern lowered levels of a hunger hormone and increased fat-burning over the day, though the fat-burning results need to be confirmed in longer studies.

Another study (1), just published and involving the same research team, reports further results of the ‘early time-restricted feeding” strategy. Comparing the two different eating patterns described above, participants on the early time schedule had improved glycemic control by lowering 24-hour glucose levels. This may be due to eating earlier and less time between meals.

The eating pattern also altered expression of circadian clock genes and increased expression of the SIRT1 anti-aging and stress response gene.

The authors suggest that the early eating pattern could have beneficial metabolic and anti-aging effects.

This eating strategy is really a form of intermittent fasting that involves having a longer daily fasting period. Intermittent fasting (a diet cycling between regular periods of eating and fasting) has been linked to lower risks of heart disease, diabetes, cancer, and aging.

Hopefully the findings of the current study will hold up when tested for longer periods of time in the future.

Women Benefit from Around 4,000 Steps Daily

The idea that it takes 10,000 steps per day to increase longevity has been ingrained in advice from health professionals and fitness trainers since the mid-1960’s. Many people using pedometers to track their steps aim for that “magic” number. But results of a new Harvard study (2) suggest that a far less daunting amount of steps – as few as 4400 daily – leads to longevity benefits, at least in older women.

In the study, 16,741 women (average age of 72) wore accelerometer devices over a week to track the number of steps taken and the intensity of those steps. The women were divided into 4 groups based on how much they walked during that week. The researchers then followed the women for an average of 4.3 years to see how many died in each of the groups.

Women who took 4,400 steps daily (roughly 2 miles) had lower mortality rates than those walking 2,700 steps per day. There were additional longevity benefits for those who walked more, but those benefits maxed out at around 7,500 daily steps.

The study authors advise not to lower your goal if you already get 10,000 steps per day. They point out that there may be additional benefits such as better quality of life or cognition that weren’t measured in this study. But if you don’t get that many steps, don’t be discouraged. All steps count, not just those taken in walking or other exercising. And, as this study shows, you can reap benefits from a much lower number than 10,000 steps daily.

The researchers also say that they’re continuing to follow the women in this study with the hopes of reporting other outcomes in the future.

References

1. Jamshed H, et al. Early time-restricted feeding Improves 24-hour glucose levels and affects markers of the circadian clock, aging, and autophagy in humans. Nutrients. 11:1234, 2019.
2. Lee I-M, et al. Association of step volume and Intensity with all-cause mortality in older women. JAMA Inter Med. Epub May 29, 2019

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In the news:New Frontiers in Probiotic & Prebiotic Research

Role for ‘Probiotics’ in Metabolic Syndrome?

We’re learning that the gut microbiota seems to affect nearly all aspects of human health – from brain function to the immune system. But we’re only just beginning to understand how differences in the composition of gut bacteria may influence our health. One area of research coming to the forefront is if and how gut bacteria might contribute to obesity.

Evidence linking gut microbiota to obesity comes mostly from animal studies, but a recent pilot study (1) published in the prestigious journal Nature Medicine, suggests that the microbiota-obesity connection could prove to be important in humans too. The study was conducted in adults with metabolic syndrome – a cluster of conditions, which can include hypertension, insulin resistance, high triglycerides, low HDL, and a large waist size.

A research team from Belgium, Finland and the Netherlands randomized 32 overweight or obese volunteers with metabolic syndrome to receive live bacteria, pasteurized bacteria (killed with heat) or placebo. The bacterium tested was Akkermansia muciniphila – a bacterium normally found in the gut, but at lower levels in those with metabolic syndrome and some inflammatory bowel conditions.

At the end of 3 months, insulin sensitivity, total cholesterol levels and biomarkers of inflammation and liver dysfunction were improved in those taking the pasteurized bacteria vs. the participants taking the placebo. That group also experienced slight decreases in body weight, fat mass and waist circumference compared to placebo takers, though the differences failed to achieve statistical significance.

Interestingly, the live bacteria did not appear to produce the same benefits as the pasteurized bacteria. While the overwhelming majority of clinical studies examining the effects of probiotics on health parameters have been performed with viable or live bacteria, a few studies have also found beneficial effects when testing supplemental non-viable bacteria. That seems to be the case in this study as well.

Obviously, these findings must be replicated in larger and longer trials to confirm their validity. But scientists appear to be on the right path to find out whether there’s a role for specific gut bacteria alongside the cornerstones of regular exercise and a healthy diet for fighting obesity and obesity-related conditions.

Be Consistent with Prebiotics for Benefits

Fiber-rich foods in general encourage the growth of healthy microbes. The inulins, in particular, belong to a class of dietary fibers known as fructans. Inulin-type fructans (ITF) resist breakdown by our digestive enzymes and are fermented to produce healthful short chain fatty acids that provide fuel for maintaining the intestinal lining. ITF also selectively stimulate growth of healthful bacteria such as biidobacteria.

In a recent study (2), healthy volunteers were assigned a diet providing ITF-rich vegetables (about 15 grams ITF/day). Food-related behavior, microbiota com-position, and GI symptoms were measured at the start and end of the 2-week intervention, and 3 weeks after they returned to their usual diet.

As expected, the high ITF increased Bifidobaterium genus and decreased levels of unclassified Clostridiales. Oxalobacteraceae (associated with lower risk of kidney stone formation) tended to be reduced as well. The participants showed greater satiety (feeling full), and less desire for sweet, salty and fatty foods. While the volunteers experienced some gas, intestinal comfort overall was improved (related to changes in microbe composition).

An important finding was that the changes in gut microbiota were only temporary, with the bacterial composition returning to pre-trial levels 3 weeks later. This underscores the importance of continuing to eat a fiber rich diet in order to maintain its beneficial effects. Along with eating high-fiber foods in general, sources of ITF include spinach, leeks, wheat, artichoke, onion, banana and garlic.

References

1. Depommier C, et al. Supplementation with Akkermansia municiphila in overweight and obese human volunteers: a proof-of-concept exploratory study. Nat Med. Epub July 1, 2019.
2. Hiel S, et al. Effect of a diet based on inulin-rich vegetables on gut health and nutritional behavior in healthy humans. Am J Clin Nutr. 109:1683-95, 2019.

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In the news: Potassium May Play a Role in Weight Loss; More on the Vitamin D – Cancer Connection

Role for Potassium in Weight Control?

It’s too early to say whether potassium might help with weight control, but the intriguing findings of a new study raise the possibility that it might.

The novel idea comes from Israeli researchers who found that participants in a weight loss study who achieved bigger reductions in their body mass index (BMI) consumed more potassium than those with only modest BMI decreases. BMI is a measure of body fat based on height and weight; A BMI of 30 or more indicates obesity.  

The study (1), which is ongoing, is looking at the effects of lifestyle changes and a diet based on a moderate low calorie, high protein Mediterranean diet in people with metabolic syndrome. This analysis was conducted using data from the first 68 men and women to complete the 1-year study. At the start of the study, the average BMI was 35. By the end of the 1-year period, BMI had declined by an average of 9.4.

Interestingly, potassium intake more strongly predicted a decline in BMI than many of the usual factors that are associated with weight loss such as cutting back on overall calories and sugar. The thirty participants whose fall in BMI was above the average reduction had upped their potassium intake by 25%. Those whose decline in BMI was below the average reduction had an increase in dietary potassium of only 3%. How potassium may be working to promote weight loss isn’t known, but the authors theorize that it might involve reducing inflammation, improving insulin sensitivity or subtle effects on energy balance.

This isn’t the first study to observe a link between potassium intake and weight loss. A recent meta-analysis of epidemiological data from several Asian studies, for example, concluded that high potassium intake was associated with lower odds of having obesity and the metabolic syndrome. But observational studies can’t prove that potassium is truly a factor in reducing BMI. Going forward, the Israeli researchers will be looking at the potassium-weight loss relation-ship in more detail.

Meanwhile, consuming more potassium makes good sense. Following either of two proven health-promoting diets, the Mediterranean and the blood pressure-lowering DASH diets, entails increasing potassium intake for example. And importantly, we’re not getting enough of this important mineral.

National Health Surveys have shown that only about 10% of men and less than 1% of women consume the daily recommended intake of 4.7 or more grams of potassium. Eat more fruit, vegetables, dairy, beans and fish to get more of this important mineral.

More on the Vitamin D & Cancer Connection

The results of observational studies suggest that higher blood levels of vitamin D are linked with lower cancer incidence and death, but the findings of intervention trials have not been clear cut or even somewhat confusing. The large VITAL trial, for example (see Staying Healthy, Dec 2018) failed to show that 2,000 IU vitamin daily for 5 years could lower the risk of invasive cancer (any type), yet it did find lower death from cancer for vitamin D v. placebo.

Two new studies offer further pieces of the puzzle. In the first study from Japan2, supplemental vitamin D did not improve relapse-free survival at 5 years for those who had undergone surgery for digestive tract cancers. But a subgroup analysis suggested some benefit for patients who started out with low blood vitamin D levels (20 - 40 ng/mL) at the study’s start.

In the second study (3), which followed more than 3800 Australians for about 20 years, lower vitamin D levels were associated with higher risk of colorectal and breast cancer, but not overall cancer risk.

As many experts have said, the jury is still out on vitamin D and cancer. So, for now, avoiding low blood levels of vitamin D is a sound strategy.

References

1. Tal B, et al. Increment in dietary potassium predicts weight loss in the treatment of the metabolic syndrome. Nutrients. 11:1256, 2019.
2. Urashima M, et al. Effect of vitamin D supplementation on relapse-free survival among patients with digestive tract cancers: The AMATERASU randomized clinical trial. JAMA 321:1361-69, 2019.
3. Zhu K, et al. Lower serum 25-hydroxyvitamin is associated with colorectal and breast cancer, but not overall cancer risk: a 20-year cohort study. Nutr Res. 67:100-7, 2019.

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In the news:Lutein Linked to Memory Performance; Nutrition Plays a Role in Skin Health

Blood Lutein Levels Linked to Memory Performance in Overweight & Obese.

The carotenoid lutein is deposited in nerve tissue and a number of regions in the brain, as well is in the eye’s macula. Research has been ongoing to better under-stand the relationship between lutein and various aspects of memory.

The current study (1), conducted by a team of neuro-scientists and nutritional researchers at the University of Illinois at Urbana-Champaign, focused on memory functions associated with the brain’s hippocampus. The hippocampus is a horseshoe shaped area in the middle temporal lobe responsible for remembering the location of objects and people, emotional responses, and assisting in the storage of long-term memories.

The research team chose to study overweight and obese participants since previous reports have linked excess fat to poorer cognitive function and brain structure, and the hippocampus is thought to be affected by obesity. Additionally, obese individuals often have lower tissue concentrations of lutein.

The diets of 94 healthy but overweight or obese adults were assessed for intake of various carotenoids (e.g beta carotene, beta cryptoxanthin), and serum levels of those carotenoids as measured, as was macular pigment density.

The participants underwent standard tests (spatial reconstruction tasks) of relational memory, which is a hippocampal-dependent process that allows us to put a name to a face or retell the story of a trip in any order we choose, for example.

After adjusting for other factors such as age, gender and body mass index, only serum lutein levels were positively linked to better performance on relational memory tasks. Other carotenoids were not, nor was macular pigment density.

According to the authors, “findings from this study indicate that among the carotenoids evaluated, lutein may play an important role in hippocampal function among adults who are overweight or obese.”

Diet, Nutrients and Skin Health

Growing evidence indicates that diet plays a role in overall skin health as well as the development of several common skin diseases, according to a new review in the dermatology journal Cutis (2).

Preliminary evidence raises promise for the Mediterranean diet in psoriasis, an autoimmune and chronic inflammatory condition. In a study that examined the association between adherence to a Mediterranean diet and the onset and/or severity of psoriasis (3), participants sticking most closely to the Med diet were significantly less likely to have severe psoriasis. Those with severe disease displayed low adherence to the diet. The reviewers also point to studies suggesting a higher rate of vitamin D deficiency in patients with psoriasis, but studies showing that supplemental vitamin D is of benefit in the condition are lacking to date.

Several studies support a role for a low glycemic index diet in reducing acne lesions and improving acne vulgaris overall. A low glycemic index diet is one rich in fruits, vegetables, unprocessed grains and ample fiber. The reviewers also discussed a randomized trial in which both omega-3 fatty acids from fish and gamma linolenic acid reduced acne lesions (both inflammatory and non-inflammatory lesions) and reduced acne severity in acne vulgaris patients.

The reviewers touched on other emerging research investigating the role of gut microflora in various conditions. They cited a study in which a supplemental prebiotic (food for gut bacteria, in this case oligo-saccharides) were given to children at risk of developing atopic dermatitis. At 6-month follow-up, 24 participants in the placebo group had developed atopic dermatitis compared to only 10 in the prebiotic group.

References

1. Cannavale CN, et al. Serum lutein is related to relational memory performance. Nutrients. 11:768, 2019.
2. Soliman YS, et al. The role of diet in preventing photo-aging and treating common skin conditions. Cutis. 103:153-6, 2019.
3. Phan C, et al. Association between Mediterranean anti-inflammatory dietary profile and severity of psoriasis: results from the NutriNet-Santé cohort. JAMA Dermatol. 154:1017-24, 2018.

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In the news: Better Nutrient Intake & Lower Cataract Risk; Tackling Dry Eye and Depression

Vitamins, Carotenoids & Lower Cataract Risk

Over the years, a number of studies have linked a better intake of certain nutrients with a lower chance of having age-related cataract. As a follow-up, university researchers in China conducted a meta-analysis of many of these studies, both observational (population-health) investigations and randomized trials (1).

Most of the nutrients evaluated in the observational studies were associated with a reduced risk for age-related cataract including: Lutein / zeaxanthin (19% lower risk), vitamin A (19%), vitamin C (20%), and vitamin E and beta-carotene (each 10%). In the intervention trials, neither vitamin E nor beta-carotene reduced risk vs. placebo.

Looking further at the observational studies, the researchers performed a dose-response analysis. They found that the risk of age-related cataract decreased by 26% for every 10-mg/day increase in lutein or zeaxanthin intake and decreased by 18% for each 500-mg/day increase in vitamin C intake.

The authors point out that slowing down the develop-ment of age-related cataract by 10 years, would reduce the number of people needing cataract surgery. We do have to keep in mind that while observational studies identify associations, they don’t prove cause and effect. Yet, we can’t go wrong by eating more citrus fruit, tomatoes and dark green vegetables – sources of lutein, vitamin C and other health-supporting antioxidant nutrients.

Dry Eye Disease & Depression Often Overlap

Many studies have found that people with dry eye disease (DED) frequently are dealing with depression too. A newly published study adds to those findings2. In short, the study found that depression is more common among patients with DED than without DED.

The researchers noted that out of 1600 consecutively enrolled participants, 30% were diagnosed with DED. And of those with DED, nearly 27% had depression, as measured by the Geriatric Depression Scale.

It may be that the chronic, painful symptoms of DED can lead to depression. Additionally, anti-depression medications often taken for depressive symptoms are considered to be a risk factor for DED and may cause or at least contribute to dry eye.

But whether depression or DED strikes first, depression may worsen DED. Research has shown that longer-term depression increases the production of pro-inflammatory molecules called cytokines, and inflammation is an important underlying factor in DED.

Tackling Depressive Symptoms: Mood & Food

DED should, of course, be treated by a health care professional, and that in and of itself could have a beneficial effect on mood for some. Improving what we eat can also have a positive impact on depression (although not major depression) and anxiety.

A newly published meta-analysis (2), for example, looked at 16 controlled trials involving over 45,000 participants most of which investigated patients with mild or non-clinical depression. Many of the trials focused on improving the diet in general, reducing unhealthy pro-inflammatory foods, limiting fat intake or weight loss. One study – the SMILES trial – found significant improvement of depressive symptoms with the Mediterranean (Med) diet. Another trial (not included in this meta-analysis) found benefit from a Med diet plus fish oil supplementation.

The meta-analysis authors conclude that dietary interventions significantly reduce depressive symptoms, with women benefiting more than men for both depressive and anxiety symptoms. Dietary changes might be acting through pathways related to oxidative stress, inflammation and dysfunction of the energy producing mitochondria in cells – pathways which can be disrupted in people with depressive disorders. Fruits and veggies also contain polyphenols that have been linked to reduced rates of depression in some observational studies.

References

1. Hong Jiang, et al. Dietary vitamin and carotenoid intake and risk of age-related cataract. Am J Clin Nutr. 109: 43,54, 2019.
2. Firth J et al. The effects of dietary improvement on symptoms of depression and anxiety: A Meta-analysis of Randomized Controlled Trials. Psychosom Med. Feb. 5, 2019.

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In the news: Low Vitamin D, Overweight and Back Pain; Cholesterol Controversy is Back…

Overweight with Back Pain? Vitamin D Levels

Chronic back pain can really limit a person's activities and affect their quality of life. Back pain is, in fact, the greatest cause of disability worldwide, and treatment options are limited.

Vitamin D deficiency and overweight are each risk factors for lower back pain in both men and women. There is also a connection between obesity and vitamin D status. Compared to non-obese individuals, lower levels of serum vitamin D are more common in those who carry around too much body fat.

People who have a body mass index of 30 or more may need larger than usual intakes of vitamin D to achieve serum levels that are comparable to those found in normal weight individuals. One reason appears to be that the greater amount of subcutaneous fat (the jiggly fat just under the skin) stores more of the vitamin, and alters its release into the circulation where it can do its job.

Australian researchers recently studied (1) overweight and obese people with lower back pain and low vitamin D blood levels (less than 50 nmol/L). Study participants were given high amounts of supplemental vitamin D or placebo over a 16-week period.

After accounting for other factors that can affect back pain or vitamin D levels, the investigators found that 20 participants who had very low blood levels (less than 30 nmol/L at the study’s start) experienced a greater reduction in back pain disability scores compared to those given a placebo. The authors suggest that increasing very low vitamin D blood levels can improve back pain in the overweight and obese.

The Egg and Cholesterol Riddle

Whether eating dietary cholesterol, including eggs, is linked to cardiovascular disease (CVD) and death has been debated for decades. Earlier US Dietary Guidelines urged Americans to eat less than 300 mg of dietary cholesterol daily, while the 2015-2020 US Dietary Guidelines are more relaxed and omit a daily limit on cholesterol intake.

Now, a large-scale analysis from Northwestern University has made headlines with findings that eating 300 mg of cholesterol daily is associated with a 17% higher risk of CVD and that eating 3-4 eggs weekly is linked to a 6% higher risk of CVD (2). The study does have limitations. For example, cholesterol intake was based on a single snapshot of the diet in time, and diets can change over time. However, the study was a comprehensive review and analysis that is getting a lot of attention.

At the same time, another large study (3) from the University of Sydney reports that eating 2-4 eggs weekly at baseline is associated with a 62% lower risk of late stage AMD compared to people eating 1 or less eggs weekly after 15 years of follow-up. Egg yolks contain bioavailable lutein and zeaxanthin as well as about 186 mg of cholesterol per 1 large egg.

Avoid Eggs or Eat Them in Moderation?

The first thing to keep in mind is that dietary intake of cholesterol from eggs, red meat, processed meat and high-fat dairy like butter and whipped cream, affect individuals differently. Some people can consume eggs regularly and very little is gets into the blood stream, while others have blood cholesterol that is more responsive to the amount of cholesterol consumed. In other words, genetic and metabolic factors interact to influence whether the amount of dietary cholesterol consumed impacts the amount of cholesterol in blood.

It’s a good idea to know your blood cholesterol numbers (e.g. total and LDL cholesterol), and to work with your own physician to decide whether curtailing dietary cholesterol is right for you. In the meantime, eating eggs in moderation – perhaps 2 per week – seems reasonable, particularly if dietary cholesterol overall is not excessive.

References

1. Brady SRE, et al. Vitamin D supplementation may improve back pain disability in vitamin D deficient and overweight or obese adults. J Steroid Biochem Mol Biol. 185:212-217, 2019.
2. Zhong VW, et al. Associations of dietary cholesterol or egg consumption with incident cardiovascular disease and mortality. JAMA. 321:1081-1095, Mar, 2019.
3. Gopinath B, et al. Consumption of eggs and the 15-year incidence of age-related macular degeneration. Clin Nutr. Epub March 16, 2019.

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In the news: Low Omega-3 Intake; How to Store Olive Oil; Fruits, Veggies for Mental Well-Being

Omega-3 Intakes Low for Most Americans

Despite the importance of n-3 fatty acids for health at all stages of life, surveys have shown that intakes remain below recommended levels for most in the US. A new study (1) analyzed data from 45,347 participants of the US National Health and Nutrition Exam Survey to provide an updated assessment of fish, EPA and DHA intake by age, gender and pregnancy status. Key groups identified as not consuming recommended amounts of omega-3 include:

• Pregnant women – who consumed less than 20% of the 520 mg daily of EPA + DHA recommended by the National Institutes of Health Workshop;
• Children 1-3 and 4-8 – who consumed about 40% of the intake recommended by the Institute of Medicine for their age group;
• Adults and Seniors – who fared slightly better, consumed about 60% of the minimum intake of EPA + DHA recommended by many organizations.

They also noted that women, in general, consumed significantly less omega-3 than men. Eating below-recommend intakes of EPA and DHA is especially important during pregnancy because these fatty acids are important for the unborn baby’s developing brain and visual system. Pregnant women who eat more omega-3 are also less likely to have a premature birth.

The omega-3s continue to be uniquely important for infants and toddlers as the brain continues to grow and develop at a rapid pace after birth to about age 3 and continues to grow through age 5.

Adults and seniors benefit from the anti-inflammatory activity of these fatty acids that support mood, brain and cardiovascular function. Consuming more fatty fish and/or supplementing dietary intake with fish oil is important for people of all ages and gender.

How to Keep Olive Oil’s Healthy Nutrients

Along with oils from fatty fish, extra virgin olive oil is another healthful component of our diet. But how should this oil be stored in order to best keep its
quality and its beneficial phenolic (antioxidant) compounds intact as long as possible? Spanish food science researchers set out to answer this question by studying the quality and phenol content of extra virgin olive oil after storage for 1 year in different types of containers under dark or light conditions (2).

The results showed that total phenol content diminished 52-65% when stored in plastic (poly-ethylene) containers exposed to light, and 43-65% in clear glass bottles with light exposure. For containers kept in the dark, the phenolic loss was 26-41% in plastic bottles, but only 10-15% in dark glass bottles. Fruity taste was best retained in dark glass kept away from light.

Take-home message: To keep extra virgin oil at its best, buy it in dark glass bottles and store it away from light in a cool place. This makes sense since oxygen (a culprit in degrading oils) can pass through plastic, and light and heat also contribute to degradation.

“Lettuce be Happy”: More Fruits & Veggies

It’s well known that that eating fruit and vegetables can benefit physical health. A new study (3) by UK research team suggest that it can also benefit psychological well-being. After analyzing data from over 40,000 people and taking into account other factors that might affect mental well-being, the researchers report that changes in fruit and veggie intake are correlated with changes in mental well-being.

Specifically, the findings indicate that eating just one extra portion of fruits and vegetables daily could have an equivalent effect on mental well-being as around 8 extra days of walking per month (for at least 10 minutes at a time).

“While further work is needed to demonstrate cause and effect, the results are clear: people who do eat more fruit and vegetables report a higher level of mental well-being and life satisfaction than those who eat less”, according to the lead investigator.

References

1. Thompson M, et al. Omega-3 fatty acid intake by age, gender and pregnancy status in the United States: National Health and Nutrition Examination Survey 2003-2014. Nutrients. 11:177, 2019.
2. Torres-Robles A, et al. Effect of light exposure on the quality and phenol content of commercial extra virgin olive 0il during 12‐month storage. JAOCS. Epub Feb. 6, 2019.
3. Ocean N, et al. Lettuce be happy: A longitudinal UK study on the relationship between fruit and vegetable consumption and well-being. Soc Sci Med. 222:335-45, 2019.

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In the news: Omega-3s Slow Muscle Loss with Disuse Good Vitamin D Levels? Think Magnesium

Omega-3 Fatty Acids May Help Muscles

The saying ‘use it or lose it’ is often used to describe what happens to muscles when they’re inactive. Muscles tend to shrink or ‘atrophy’ from lack of physical activity when injury or disease makes it difficult or impossible to move an arm or a leg.

Because omega-3 fatty acids play a role in muscle protein production, researchers at McMaster University's Department of Kinesiology in Canada decided to study whether fish oil supplementation could slow the loss of muscle mass during periods of muscle disuse due to immobilization (1).

This small but novel study involved 20 healthy young women who received either high dose fish oil or a placebo for 4 weeks.

At the end of that 4-week period, the participants each wore a knee brace that immobilized one leg for 2 weeks. The women then entered a recovery phase for another 2 weeks, during which they went back to their normal everyday activities.

The researchers measured leg muscle size, mass, strength and protein synthesis before and after the immobilization, as well as after the recovery period. The results showed that the fish oil group lost significantly less muscle volume (size) compared to the placebo group. Muscle volume also returned to pre-immobilization levels after the recovery period for the fish oil group, while it remained lower in the placebo takers. Muscle mass (the amount of muscle) was reduced only in the placebo group.

Analysis of muscle tissue samples taken from the participants revealed that muscle protein production was higher in the omega-3 group than in the placebo group throughout the study.

According to the lead author, the findings suggest that young women may be able to use supplemental omega-3 to slow muscle loss and enhance recovery in situations where one of their limbs is immobilized.

Magnesium Crucial for Vitamin D Metabolism

A recent trial (2) by Vanderbilt-Ingram Cancer Center researchers found that a more optimal intake of magnesium can optimize vitamin D status, raising it in people with deficient levels, and lowering it in people with high levels.

The Vanderbilt findings could help explain the inconsistent results seen in population health and clinical studies that have looked at vitamin D and the risk of colorectal cancer and heart disease.

Because magnesium is required to fully activate vitamin D, having inadequate levels of this mineral can mean that much of vitamin D in the body remains stored and inactive. This is important because national surveys indicate that 79% of American adults don’t meet the RDA for magnesium.

The study included 180 participants at high risk of colorectal cancer, who received either a placebo or supplemental magnesium in amounts that were customized for each person based on their baseline levels of dietary intake.

The amounts of magnesium were tailored to bring the participant’s calcium to magnesium intake ratio to about 2.3. The average amount supplemented was a little over 200 mg of magnesium daily.

These study results are in agreement with those of an earlier study (3) by the same researchers that linked higher magnesium (from diet, supplements or both) with a lower risk of vitamin D inadequacy /deficiency.

The take home message? If you’re trying to improve your vitamin D levels, don’t forget magnesium. Good sources include dark leafy greens, beans, whole grains, fatty fish and nuts.

References

1. McGlory C, et al. Omega-3 fatty acid supplementation attenuates skeletal muscle disuse atrophy during two weeks of unilateral leg immobilization in healthy young women. FASEB. Epub ahead of print Jan, 2019.
2. Qi Dai, et al. Magnesium status and supplementation influence vitamin D status and metabolism: results from a randomized trial. Am J Clin Nutr. 108:1249–58, 2018.
3. Deng X, et al. Magnesium, vitamin D status and mortality: results from US National Health and Nutrition Examination Survey (NHANES) 2001 to 2006 and NHANES III. BMC Med. 11:187, 2013.

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In the news: Omega-3 Lowers Risk of Premature Birth; Choose Organic Foods When Possible

Premature Births a Global Problem

Premature birth is the leading cause of death for children under 5 years old worldwide, according to the authors of a new review on omega-3 fatty acids during pregnancy and premature birth. And it’s not just a challenge facing poorer, developing countries. Pre-mature birth is the leading cause of newborn death here in the US as well. Also concerning is that the rate of preterm births in the US has risen over each of the past 3 years.

While most pregnancies last between 38 and 42 weeks, babies born before the 37-week mark are considered premature. According to the Centers for Disease Control, preterm babies remain at a higher risk of having problems later in life, like cerebral palsy, vision and hearing problems – and the earlier a baby is born, the greater the risk of poor health.

Omega-3s Reduce Risk of Preterm Births

The independent Cochrane Reviews is internationally recognized as the most rigorous kind of critical review in the health care field. An Australian team of researchers recently conducted a Cochrane review, with the aim of assessing whether high-quality evidence supports omega-3 supplementation as an effective strategy for preventing premature births (1).

The team looked at over 70 clinical trials involving nearly 20,000 women that compared increased intake of omega-3 fatty acids (EPA and DHA) as supplements or foods to placebo during pregnancy. They found that higher omega-3 intake reduces the risk for having a:

• premature baby (less than 37 weeks) by 11%;
• earlier premature baby (less than 34 weeks) by 42%;
• small newborn (less than 5.5 lbs) by 10%.

The new review is an update of a similar review conducted in 2006. That review concluded that more evidence was needed to support the routine use of omega-3 fatty acid supplements during pregnancy.

In contrast, the 2018 update concludes that high-quality evidence now supports such supplementation for helping to prevent premature births.

Based on the review, an optimal dose appears to be daily supplemental intake of 500-1,000 mg of long-chain omega-3 fats (EPA/DHA) containing at least 500 mg of DHA, and commencing at about 3 months of pregnancy.

Advantage of Eating Organic Foods?

A new large-scale study (2) has shown a link between consuming an organic food-based diet and a lower risk of cancer.

The researchers – a French team from the Center of Research in Epidemiology and Statistics – point out that their results need to be confirmed since organic food consumption is difficult to assess. But if their findings hold, choosing organic foods when possible may be advantageous. It’s also good to keep in mind though, that, overall, eating fruits and vegetables is health-promoting, organic or not.

The study examined the diets of nearly 69.000 French adults who were followed about 4 ½ years on average. The participants reported how often they consumed a variety of organic foods – never, occasionally or most of the time.

The highest consumers of organic foods were found to have a 25% reduction in overall cancer risk compared to consumers with a low frequency of organic food intake. For certain cancers the risk was even lower. The researchers observed a 34% decrease in risk of post-menopausal breast cancer, and a 76% decrease in lymphoma cancer.

References

1. Middleton P, et al. Omega-3 fatty acid addition during pregnancy. Cochrane Database of Systematic Reviews, Nov. 15, 2018.
2. Baudry J, et al. Association of frequency of organic food consumption with cancer risk: Findings from the NutriNet-Santé Prospective Cohort Study. JAMA 178:1597-1606, 2018

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In the news: Can Eating Leafy Greens Lower AMD Risk? Findings From the VITAL Study

Leafy Greens & Eye Health

Leafy green vegetables contain nutrients – lutein, zeaxanthin and vitamin C, for example – that are beneficial to eye health. Now, for the first time, Australian medical researchers report a link between eating vegetable nitrates, abundant in leafy greens and beets, and the risk of developing early age-related macular degeneration (AMD) (1).

The body naturally produces nitric oxide, which plays a number of roles in overall health. One important function of nitric oxide is vasodilation – the relaxation of blood vessels to allow good circulation. Dietary nitrates can be converted to nitric oxide once consumed.

In the present study, researchers used data from over 2,000 participants of the Blue Mountains Eye Study – a large population health study conducted in Australia. Those participants had complete dietary data and information about age-related macular degeneration (AMD), and were re-examined 15 years later.

After taking into account other risk factors that could affect AMD development, the researchers found that those who consumed a moderate amount of vegetable-sourced nitrates each day (100-142 mg) had a 35% lower risk of developing early-stage AMD compared to those who ate less than 69 mg of vegetable nitrates daily.

Eating higher amounts of vegetable-sourced nitrates (greater than 142 mg daily) was not associated with risk reduction, nor did nitrate intake influence the risk of late-stage AMD.

More research must be conducted to see if the association of dietary nitrates and AMD holds up. If the findings are confirmed, dietary nitrates may be another good reason to eat leafy greens (dark leafy greens especially), and beets – vegetables that already established as important for overall health.

Findings from the VITAL Study

The VITAL Study evaluated whether vitamin D (2,000 IU daily) and fish oil (1,000 mg daily) could lower the risk of invasive cancer of any type or major cardiovascular events (a composite of heart attack, stroke, or death from cardiovascular disease) in over 25,800 men and women who were free of cancer and cardiovascular disease at the beginning of the study, and followed for about 5 years (2), (3).

These primary objectives or target endpoints of the study were not met for vitamin D or the omega-3s.

Despite this, separate analyses (called secondary findings) are promising, particularly the lower death from cancer seen for vitamin D compared to placebo. Secondary findings need to be interpreted cautiously, especially because the trial was unable to include some relevant statistical corrections.

However, the vitamin D findings are in line with those from a recent meta-analysis that showed a significant benefit with vitamin D and cancer mortality. Also, another VITAL analysis found that the rate of cancer death was lower with vitamin D vs. placebo when the first 2 years of the study were excluded.

While fish oil didn’t lower all major cardio events as a group (a primary endpoint), a reduction in risk was seen for heart attack, fatal heart attack, and total coronary heart disease when each was looked at separately.

It’s also worth noting that analyses revealed a risk reduction for the primary cardiovascular endpoint with fish oil supplements vs. placebo for those with low fish intake (less than 1½ servings weekly) at the study’s start. No risk reductions were seen for participants with higher fish intake.

In terms of safety, no adverse effects were seen for vitamin D or omega-3 supplementation in VITAL, including no excess bleeding or high blood calcium.

References

1. Gopinath B, et al. Association of dietary nitrate intake with the15-Year incidence of age-related macular degeneration. J Acad Nutr Dietetics. Epub Oct 17, 2018.
2. Manson JE, et al. Marine n-3 fatty acids and prevention of cardiovascular disease and cancer. NEJM. Epub Nov. 10, 2018.
3. Manson JE, et al. Vitamin D supplements and prevention of cancer and cardiovascular disease. NEJM. Epub Nov. 10, 2018.

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In the news: Dark Chocolate May Support Some Measures of Vision and Attention

Dark Chocolate: More Than a Sweet Delight

If you’re already a fan of dark chocolate, you probably know that this sweet treat also brings the promise of health benefits. Dark chocolate or cocoa consumption has been linked to a lower risk of heart disease, for example, most likely due to reducing blood pressure and inflammation. Compared with milk chocolate, the dark version is far more abundant in flavanols – a type of bioflavonoid that has been shown to promote the production of artery-relaxing nitric oxide.

Two recent studies have explored the effects of cocoa or dark chocolate on vision and cognitive function. The findings, though preliminary, suggest that these flavanol-rich foods could help support visual function and some aspects of cognitive function as well.

Dark Chocolate May Support Eyesight

While studies have shown that dark chocolate can improve blood flow, mood, and cognition in the short term, not much is known about the possible effects of dark chocolate on visual performance. To learn more, university researchers compared the effects of milk vs. dark chocolate on visual testing in 30 healthy adults without eye disease (1).

Every participant ate a dark and a milk chocolate bar in separate sessions, with visual tests conducted about 1 ¾ hours after consumption. The dark chocolate bar (47 g, 72% cacao) contained 316 mg of flavanols, while the milk chocolate bar (40 g, 12.4 g milk chocolate cocoa) contained 40 mg of flavanols, about 8 times less than the dark bar.

The researchers found that small-letter contrast sensitivity was higher after the dark chocolate bar was consumed compared to the milk chocolate bar. Large-letter contrast sensitivity was slightly higher as well. Contrast sensitivity is the ability to distinguish an object – in this case small and large letters – from its background.

Visual acuity – clarity or sharpness of vision – was also slightly enhanced after the dark chocolate was eaten.

When the results from all tests were combined, there were significant improvements after dark vs. milk chocolate consumption.

The authors concluded that further testing is needed to understand how these effects will influence ‘real-world’ visual performance and how long the effects may last. They also theorize that the improvements seen may be due to flavanols increasing blood flow to bring more oxygen and nutrients to eye tissues.

Cocoa Flavanols May Support Attention

A number of previous studies have sought to understand if and how dark chocolate or cocoa might affect various aspects of brain function and mood. In the current investigation, researchers explored the effects of cocoa flavanols on spatial and temporal attention.

To study this question, 48 university students were enrolled in the trial with each of them completing experimental tasks in separate sessions: at baseline, after taking a placebo, after supplemental low dose flavanols (373 mg) and high dose flavanols (747 mg) (2).

Neither dose of flavanols influenced the outcome of all the tests, but both the low and high dose flavanols improved the students’ visual search efficiency – a measure of attention that requires determining whether an object is present or absent in a changing visual array of items, including items meant to distract the participant. Reaction times on this test were significantly faster after flavanol consumption.

The findings suggest that flavanols may affect some aspects of attention, but not others. More research is needed to learn about the influence of dark chocolate and natural cocoa on brain function. In the meantime, treat yourself to a dark chocolate bar – it’s good for the heart, and perhaps and the mind, mood and vision too.  

References

1. Rabin JC, et al. Effects of milk vs. dark chocolate consumption on visual acuity and contrast sensitivity within 2 hours: A randomized clinical trial. JAMA Ophthalmol 136:678-681, 2018.
2. Karabay A, et al. The acute effects of cocoa flavanols on temporal and spatial attention. Psychopharmacol. 235: 1497–1511, 2018.

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In the news: Specific Exercise & Diet Can Help Prevent Falls as We Age

Tai Chi for Preventing Falls in Mature Adults

As we grow older, we face a greater risk of falling – a common cause of injury in the elderly. Maintaining our balance is crucial to preventing these potentially disabling tumbles. But how do we preserve good balance? Exercise is a key component, according to a recent review of studies looking at the impact of exercise in preventing falls (1). But that brings up a second question: What kind of exercise programs are most effective at helping to achieve good balance?

A team of researchers from Oregon recently took on that question, and the results of their study were published in the September issue of the journal JAMA Internal Medicine (2). They report that tai chi (also called tai ji quan) is more effective than conventional exercise approaches at preventing falls in high-risk, older people.

The study included 670 independently living adults, 70-years or older, who had fallen in the preceding year or had impaired mobility. Participants were randomly assigned to one of three 60-minute, twice-weekly exercise classes: 1) tai chi; 2) stretching exercises (considered the control group); or 3) exercises that integrated balance, aerobics, strength and flexibility.

At the end of 24 weeks, the tai chi intervention reduced falls by 58% compared with the stretching exercise, and by 31% compared with the conventional integrated exercises.
 
There are many advantages to tai chi: It’s slow and gentle, yet improves both upper- and lower-body muscle strength, balance, flexibility and, to a lesser degree, aerobic conditioning. Remember, too, that tai chi can be combined with other exercises you may do such as swimming, stationary biking, or work with hand weights and resistance bands.

What Else Can You Do to Help Prevent Falls?

From a nutrition standpoint, making sure you are not vitamin D deficient or consuming too little protein are important. Poor vitamin D levels have been linked to increased risk of falling in people over 70. First, vitamin D insufficiency can lead to reduced bone mass density which puts people at greater risk for fractures when they fall. In addition, vitamin D deficiency increases the chances for muscle weakness. vitamin D is needed to transport calcium into muscle cells, enabling muscles to contract. vitamin D also plays a regulating role in building and repairing muscle fibers. The daily recommended intake for vitamin D is 800 IU for those 70 and older.

With advancing age, people tend to lose muscle mass as well as muscle strength (called sarcopenia), both of which have been linked to falls and fractures (3).

Studies have shown that consuming about 20-30 g of protein (about 3-4 oz. ounces of protein-rich foods) 3 times daily promotes muscle growth in both young and old alike. Include protein foods that are good sources of leucine (e.g. cheese, beef, chicken, pork, fish, nuts and beans), as this amino acid can stimulate protein synthesis in muscles.  

Finally, take stock of and address other factors that can lead to poor balance and falls. Examples include: inner eye problems, hearing loss, vision changes or decline, pain, foot problems, arthritis of the knee, low blood pressure or other causes of dizziness, and some medications (e.g. blood pressure-lowering, sleep inducing, anti-convulsant, and antidepressant drugs).  

So, to move with better balance, comfort and confidence: Do appropriate exercises regularly; Consume sufficient protein and vitamin D daily; and Identify and find solutions for other related factors.

References

1. Sherrington C, et al. Exercise to prevent falls in older adults: an updated systematic review and meta-analysis. Br J Sports Med. 51:1749–1757, 2017.
2. Fuzhong Li, et al. Effectiveness of a therapeutic tai ji quan intervention vs a multimodal exercise intervention to prevent falls among older adults at high risk of falling: A randomized clinical trial. JAMA Intern Med. Published online September 10, 2018.
3. Clynes MA, et al. Definitions of sarcopenia: Associations with previous falls and fracture in a population sample. Calcified Tissue International. 97 (5), 2015.

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In the news: Flavonoid-Rich Foods and Walnuts For Intestinal Health

The Microbiota of the Intestinal Tract

We each have a collection of microbes or micro-organisms that call our bodies home. Our microbiome is made up of unique communities of these microbes called microbiota that inhabit the skin, mouth, eyes, genitals, and of course, the intestines. The intestinal microbiota is composed of a multitude of bacterial species (along with some fungi and viruses), and is referred to as “gut flora”.

Research has already revealed that gut microbes can affect the health of the gut locally, and that they can influence our immune response. Potentially, they also influence the brain and behavior. While scientists continue to unravel what constitutes a healthy balance of these inhabitants, there is evidence that our diet can make a difference in promoting a broad range of healthful bacteria in the gut.

A plant-based diet focused on fruits, vegetables, nuts, beans and whole grains seems to be key. Not only is the undigestible fiber they contain a “food” for beneficial bacteria, but other components in plant-based foods may also play a role in supporting healthful bacteria as new research suggests.

Polyphenols in Tart Cherries, Blueberries

The polyphenols (flavonoids) seem to mutually benefit bacteria and ultimately us, their hosts. Gut bacteria metabolize polyphenols into forms that we better absorb, and polyphenols may influence the make-up of gut flora by inhibiting bad bacteria and stimulating beneficial types.

University of Arkansas researchers, for example, have recently provided evidence that tart cherries and the flavonoids they contain such as anthocyanins, may positively influence the gut microbiota (1).

In lab studies that imitate the condition of human digestion along the GI tract, the researchers found that gut microbes were able to break down anthocyanins and other flavonoids, and increase a gut-friendly type of bacteria. When healthy adults drank 8 oz. of tart cherry juice daily in the second part of the study, they
found that the microbiota was favorably altered.

Interestingly, the type of friendly bacteria that was altered in participants who typically ate a more plant-based diet (Bacteroides and Bifidobacterium) was different than in those consuming a more Western diet (Collinsella).

In another, longer study (2), US and Italian researchers teamed up to test the effects of drinking a powdered blueberry drink on gut flora. Healthy men were randomly assigned to the blueberry beverage or placebo for 6 weeks, and then switched over to receive the other beverage for an additional 6 weeks.

While participants varied in their response, stool sample analysis showed that the blueberry drink increased a Bifidobacterial strain (B. longum subsp infantis) that has been reported to favorably influence the immune system and to have “demonstrated health-promoting activity” according to the authors.

Walnuts Beneficially Change Gut Flora

A study from the University of Illinois suggests that eating walnuts may be another way to produce beneficial changes in the gut microbiota (3). Walnuts contain fiber, “good” fats, and other plant compounds.

In the study, healthy participants consumed 48g of walnuts (about ½ cup) each day for 3 weeks, and then no walnuts for another 3 weeks.

Eating the nuts increased certain bacteria that produce a short chain fat (butyrate) that is anti-inflammatory and helps protect the walls of the intestine. The walnuts also reduced pro-inflammatory bacterial metabolites and, as a bonus, lowered LDL cholesterol.

References

1. Mayta-Apaza A, et al. Impact of tart cherries polyphenols on the human gut microbiota and phenolic metabolites in vitro and in vivo. J Nutr Biochem 59:160-72, 2018.
2. Guglielmetti S, et al. Differential modulation of human intestinal Bifidobacterium populations after consumption of a wild blueberry (Vaccinium angustifolium) drink. J Agric Food Chem. 34:8134-40, 2012.
3. Holscher HD, et al. Walnut consumption alters the gastrointestinal microbiota, microbially derived secondary bile acids, and health markers in healthy adults: a randomized controlled trial. J Nutr. Epub May, 2018.

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In the news: Flavonoids May Benefit Cardio- Metabolic, Eye and Cognitive Health

Anthocyanins and Cardio-Metabolic Health

Cardio-metabolic risk refers to your chances of developing diabetes, heart disease or stroke, and includes such risk factors as elevated blood sugar, cholesterol, and blood pressure, and being overweight. Several, but not all, previous clinical investigations suggest a cardio-metabolic role for anthocyanins, the (flavonoid)s that give color to foods like eggplants, red cabbage, blueberries, blackberries, raspberries and concord grapes. Consuming more polyphenols in general (flavonoids are a type of polyphenol) has been tied to lower type 2 diabetes risk (1).

To better understand the effects of anthocyanins on cardio-metabolic risk factors, researchers conducted a review and meta-analysis which included 19 good quality randomized clinical trials investigating anthocyanin supplementation at different doses and over differing periods of time in adults (2).

One factor showing a beneficial response to anthocyanins in this analysis was improvement in a measure of insulin resistance (called HOMA-IR). In addition, a daily dose of more than 300 mg of anthocyanins (roughly, more than ¾ cup blueberries) for at least 3 months had favorable effects on blood levels of total and LDL cholesterol.

The average intake of anthocyanins in the US is a mere 12.5 mg daily. So, bring on the red and purple fruits and veggies to support cardio-metabolic health.

Flavonoids and AMD Risk

In a new study from Australia (3), university investigators followed a group of over 2000 participants of the Blue Mountains Eye Study aged 49 and older. The group’s diet was assessed for flavonoid intake, and the presence of AMD was determined based on retinal photographs. Fifteen years later, the researchers uncovered a protective link between dietary intake of flavonoids and the likelihood of having AMD.

Greater total overall flavonoid intake was associated with a 24% reduced chance of having any AMD. Several classes of flavonoids (flavanones which are abundant in citrus, and flavonols, found in a wide variety of foods such as onions, kale, leeks, broccoli, blueberries, red wine and tea) were particularly linked with lower risk. A 61% reduced risk of late AMD was seen after 15 years in those who consumed one or more servings of oranges daily at the study’s start, vs. non-consumers.

Further studies are needed to confirm these findings. It’s possible, for example, that participants could have changed their diets over the years. However, the findings do make sense since greater intake of fruits and vegetables has previously been shown to reduce AMD risk, and flavonoids have antioxidant and anti-inflammatory activities. It’s also notable that the total flavonoid intake in this study group (median 875 mg/day) is vastly higher than the US intake (median 117 mg/day).

Flavonoids, Aging and the Mind

French researchers carried out a clinical trial (4) to evaluate the effects of a daily polyphenol-rich extract from grape and blueberry (containing 258 mg flavonoids) vs. placebo on memory performance in 215 healthy older subjects 60-70 years-old.

After 6 months, no improvements for the group as a whole was seen in the memory tests conducted. However, in a subgroup with the greatest cognitive decline at the study’s start, there was a significant favorable response to the flavonoids for episodic memory – the ability to mentally recall and verbalize past personal experiences occurring at a particular time and place. Hopefully this study will spur more research interest in flavonoids and memory with age.

References

1. Rienks J, et al. Polyphenol exposure and risk of type 2 diabetes: dose-response meta-analyses and systematic review of prospective cohort studies. Am J Clin Nutr. 108:49-61, 2018.
2. Daneshzad E, et al. Effect of anthocyanin supplementation on cardio-metabolic biomarkers: A systematic review and meta-analysis of randomized controlled trials. Clin Nutr. Epub ahead of print, July 2, 2018.
3. Gopinath B, et al. Dietary flavonoids and the prevalence and 15-y incidence of age-related macular degeneration. Am J Clin Nutr. 108:1–7, 2018.
4. Bensalem J, et al. Polyphenols from grape and blueberry improve episodic memory in healthy elderly with lower level of memory performance: a bicentric double-blind, randomized, placebo-controlled study.J Gerontol. Series A gly166, 2018.

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In the news: Seafood Tied to Reproductive Benefits; Omega-3s May Benefit Family Dynamics

Seafood May Help Couples Conceive Faster

When it comes to starting or expanding a family, some couples have a harder time conceiving than others. Infertility, defined as the inability to achieve pregnancy after 12 months of trying, affects 15-25% of couples in the US. Since infertility treatments are costly and not always successful, there is growing interest in identifying factors that might increase a couple’s chance of conceiving. 

A few previous studies have found a positive link between intake of the long chain omega-3 fatty acids contained in seafood, and markers of fertility in both men and women – markers such as better semen quality and increased levels of progesterone levels (a hormone that helps prepare the lining of the uterus each month to receive and nourish a fertilized egg).

Against that backdrop, a Harvard research team set out to explore the relationship between seafood intake and the time it takes to become pregnant (time to pregnancy) in a group of 501 couples attempting to conceive and who had participated in a study called the Longitudinal Investigation of Fertility and the Environment (LIFE) Study (1).

The couples were followed for up to 1 year or until pregnancy was detected. Their intake of seafood was collected daily in follow-up in journals. The researchers additionally looked at sexual intercourse frequency (SIF), which was also recorded in the journals.

Couples in which both male and female partners consumed 8 or more seafood servings per menstrual cycle had a 61% shorter time to becoming pregnant than couples consuming less.

Surprisingly, male and female partners with the highest seafood intake (greater or equal to 8 servings/ menstrual cycle) also had a 22% higher SIF. So a difference in sexual activity related to higher seafood consumption might also be playing a role.

The researchers point out that as of January 2017, the US Food and Drug Administration (FDA) and the Environmental Protection Agency (EPA) recommend that women who are pregnant or may become pregnant eat no more than 3 seafood servings per week – a guideline that was established to limit exposure of the developing fetus to methyl-mercury and environmental chemicals present in some types of seafood.

The level of seafood consumption associated with the reproductive benefits seen in this study would be approximately 2 or more seafood servings weekly – close to the guideline recommendations.  While the authors did not mention the possibility of using supplemental fish oil omega-3s to augment seafood intake, that may also be a viable consideration.  While the results of this study are exciting, double-blind intervention studies are needed to confirm the findings. 

Omega-3s, Kids’ Behavior & Family Dynamics

A new study (2) by university and National Institutes of Health researchers suggests that supplemental omega-3s not only helps calm aggressive behavior in children, but also benefits the family as a whole.

Omega-3 supplementation had previously been shown to reduce externalizing behavior in children – behaviors such as acting out, physical aggression, disobeying rules, cheating and stealing. Evidence also suggests that improving kids’ behavior can lead to improvements in their parents’ behavior as well.

The researchers gave 1 gram of omega-3s or placebo to 200 children exhibiting aggressive behavior, and measured changes in aggressive behavior among the children’s care givers. After 6 months, and again at a 12-month follow-up, they found significant long-term reductions in psychological aggressive behavior in the adult care givers of the omega-3 supplemented kids.  Bottom line: Improving a child’s behavior may decrease overall family stress and improve family dynamics.

References

1. Gaskins AJ, et al.  Seafood intake, sexual activity, and time to pregnancy. J Clin Endocrinol  Metab. Epub May 23, 2018.
2. Portnoy J, et al. Reductions of intimate partner violence reslting from supplementing children with omega-3 fatty acids: A randomized, double-blind, placebo-controlled, stratified, parallel group trial. Aggressive Behavior. Epub May, 2018.

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In the news: Can Anti-inflammatory Diets Elevate Mood? What’s the ‘DREAM’ Study?

Eating Habits May Influence Depression Risk

Last month’s Staying Healthy featured a review on the omega-3 fatty acids and depression in older individuals. The results of that review suggest that these fatty acids may help improve mood because of their anti-inflammatory actions and by affecting the actions of neurotransmitters.

A number of studies support the idea that ongoing chronic inflammation may have a role in depression. One investigation, for example, found that people with depression had higher blood levels of the inflammatory marker C-reactive protein. Brain scans of depressed individuals have also indicated increased neuro-inflammation (inflamed nervous tissue) compared to those without depressive symptoms.

In 2014, a research team from the University of South Carolina and Harvard developed a dietary inflammatory index (DII) as a tool to assess an individual’s diet on a continuum from maximally anti-inflammatory to most pro-inflammatory. Previous research has shown that various nutrients are associated with lower inflammation levels, including fruits and vegetables, omega-3s, fiber, moderate alcohol intake, vitamins C and E, beta-carotene and magnesium. In contrast, intake of various foods – e.g. fried foods, soda, refined breads, and red meat – is linked to higher inflammatory levels in the body.

To test their assessment tool, the team first used the DII to compare three different dietary patterns already linked to pro- or anti-inflammatory effects: a fast food diet (high in sugar, fried foods, high-fat dairy products, and refined grains); a Mediterranean diet (high in whole grains, green leafy vegetables and fish, low in red meat and butter, with moderate alcohol and moderate to high olive oil); and a macrobiotic diet which is a modified traditional Japanese diet (very high in whole grains, vegetables, and beans, with lower fish, fruits, and sweeteners).

As expected, the macrobiotic and Mediterranean diets produced strong anti-inflammatory DII scores vs. the DII score for the fast food diet, which had strong pro-inflammatory potential (1). Using their DII tool, the researchers have gone on to explore the relationship of inflammatory eating patterns and many chronic diseases such as heart disease and osteoporosis.

In the newest investigation (2), the team looked at a pro-inflammatory diet and the presence of depressive symptoms in a group of older individuals. The study included over 3,600 participants (average age about 60 years) with or at risk for osteoarthritis of the knee. Over the course of an 8-year follow-up, 837 participants developed symptoms of depression.

Those consuming the most pro-inflammatory diet were found to have a 24% increased risk of developing depression compared with those eating the most anti-inflammatory diet.

The study adds to the growing body of evidence that at least some forms of depression may be affected by diet. And though more research is needed, the authors suggest that transitioning to a more anti-inflammatory diet may reduce depression risk.

DREAM Study: Fish Oil for Dry Eye Disease

You may have read about the recently published trial called the DREAM study that evaluated high dose fish oil, often as an add-on to traditional therapy, for treating dry eye. In the trial (3), both supplemental high dose fish oil or olive oil (placebo) helped alleviate the symptoms and improve objective signs of dry eye similarly, leading the researchers to conclude that fish oil seems to offer no added benefit for dry eye.

Unfortunately, the fatty acid GLA (the primary omega in SBH’s product, HydroEye) was not tested in DREAM. GLA has been better studied than fish oil in dry eye, and shown to reduce symptoms and arrest inflammation. For more about DREAM and GLA go to: www.SBH.com/DREAM.

References

1. Steck SE, et al. The Dietary Inflammatory Index: A New Tool for Assessing Diet Quality Based on Inflammatory Potential. Academy of Nutrition and Dietetics: The Digest. 49:1-9, 2014.
2. Shivappa N, et al. The relationship between the Dietary Inflammatory Inde (DII) and incident depressive symptoms: A longitudinal cohort study. J Affect Disord. Epub April 2018.
3. Dry Eye Assessment and Management Study Research Group. n-3 fatty acid supplementation for the treatment of dry eye disease. NEJM. April 13, 2018.

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In the news: Younger Women Fall Short on Omega-3s; Omega-3s May Help Depressed Older Individuals

Diets Fall Short in Omega-3s for Women Who Are or May Become Pregnant

Pregnant women and women who fall into the age range (15-44 years) where pregnancy usually occurs, aren’t eating enough omega-3 rich seafood according to a new study by Pennsylvania State University nutrition researchers.

The omega-3 fatty acids EPA and DHA are important both to a mother and her developing infant. The DHA that’s consumed by a mom-to-be may help reduce the risk of premature birth, and is important for her fetus’s brain and visual development, as well as immunity. Some studies have also linked better circulating levels of these fatty acids during pregnancy with a lower risk of postpartum depression.

The researchers analyzed data from the US National Health and Nutrition Examination Survey (2001-2014)
to see how EPA and DHA intakes among pregnant and childbearing-aged women stack up against current intake recommendations (1).

The 2015-2020 Dietary Guidelines for Americans recommend that people consume about 8 oz. per week of a variety of seafood, which equates to about 250 mg of EPA + DHA daily. During pregnancy and breastfeeding, the Guidelines call for consuming 8-12 oz. of seafood weekly.

For women in their childbearing years, the average intake was less than ½ oz of seafood daily, with 100% of this group falling short of Guideline recommendations. The average usual intake of EPA + DHA per day from seafood and supplements combined was about 88 mg – far short of the recommended 250 mg.

Similar results were seen for pregnant women, though they noted that intake had increased slightly over the 14-year period.

The authors conclude that childbearing aged, pregnant and breastfeeding women are not meeting dietary recommendations for seafood intake, and as a result have low intakes of EPA and DHA. Concern about the potential content of methylmercury in some fish may deter moms-to- be from eating more seafood. The Center for Food Safety and Applied Nutrition website offers sound advice for choosing the safest seafood during pregnancy and lactation. Greater use of fortified foods and omega-3 supplements can also help fill the EPA/DHA dietary gap.
(https://www.fda.gov/Food/FoodborneIllnessContaminants/PeopleAtRisk/ucm593058.htm).

Omega-3s & Depression in Older Individuals

Depression in older adults is fairly common, affecting roughly 6 million Americans ages 65 and older, though only 10% receive treatment for depression. While the omega-3s may hold promise in helping manage depression, there have been no reviews of intervention trials testing these fatty acids specifically in depressed people older than 65.

To better clarify the effects of the omega-3 fatty acids in older adults, researchers analyzed the results of 6 trials that included 4605 male and female patients, with an average age of 77 years (2). The average dose of omega-3 intake across the trials was 1.3 grams daily.

The review and analysis found that depressive symptoms experienced by elderly participants with mild to moderate depression improved in response to omega- 3 PUFAs, while the fatty acids had no significant effect in elderly subjects without depressed mood.

According to the authors, depression reflects a chemical imbalance in the brain, the root cause of which is excess inflammation in the body. They suggest that the omega-3s may help in depression because of their anti-inflammatory actions and by affecting the actions of neurotransmitters.

References

1. Zhang Z, et al. Dietary intakes of EPA and DHA omega-3 fatty acids among US childbearing-age and pregnant women: An analysis of NHANES 2001-2014. Nutrients 10:416, 2018.
2. Bae J, et al. Systematic review and meta-analysis of omega-3 fatty acids in elderly patients with depression. Nutr Res 50:1-9, 2018.

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In the news: Diet Sodas & Diabetic Retinopathy; Antioxidant Rich Diet & Type 2 Risk

What is Diabetic retinopathy?

One complication of diabetes is diabetic retinopathy, where high blood sugar levels damage blood vessels in the retina. The vessels can swell and leak, or become blocked and reduce blood supply to the retina.

During the more advanced form of the condition, called proliferative diabetic retinopathy, new – but more fragile – vessels can grow in the retina and into the gel-like vitreous fluid. In turn, these vessels may leak blood into the vitreous, resulting in cloudy vision.

Diet Sodas & Diabetic Retinopathy: Connected?

Those with diabetes are aware that drinking sugary sodas has long been associated with an increased risk of diabetes and cardiovascular disease (CVD). But what about diet sodas which have been marketed as “healthier alternatives” to sugar-laden sodas?

Researchers from the University of Melbourne in Australia are the first to explore whether there’s relationship between diet soda intake and the severity of diabetic retinopathy.

To do this, they surveyed over 600 diabetic patients to assess their soda intake. Patients were categorized by their stage of diabetic retinopathy, ranging from no retinopathy, to mild to severe non-proliferative retinopathy, to severe proliferative diabetic retinopathy.

The researchers found that those drinking more than 4 cans of diet soda weekly were more than twice as likely to have proliferative diabetic retinopathy versus those consuming less than a can per week (1).

Diet Sodas & Diabetic Retinopathy in Perspective

In addition to this study, others (though not all) have also linked diet soda intake to obesity, type 2 diabetes and CVD. Keep in mind, though, that these studies are observational and can’t prove cause and effect.

If drinking too many diet sodas truly is unhealthy, why? The answer isn’t clear, but the researchers point out that the artificial sweeteners in diet sodas could increase the desire for more sweet and high-calorie foods. If that leads to weight gain, it can make it harder to keep blood sugar levels within a healthy range and may up the risk of diabetic complications.

Bottom line: Until there’s a better understanding of how diet sodas might impact health, it’s probably best to keep their intake to a minimum. One alternative is to substitute sparkling water with a dash of fruit juice or an added sprig of mint for flavor.

Antioxidant Rich Diet May Lower Type 2 Risk

Of course the best way to avoid diabetic complications is to avoid getting type-2 diabetes in the first place, if possible. In addition to losing weight if overweight, exercising and eating wisely, consuming an antioxidant rich diet may help as well.

Mounting evidence suggests that oxidative stress may contribute to the development of type 2 diabetes. Oxidative stress occurs when the production of free radicals exceeds the ability of our antioxidant defenses to handle them.

French researchers looked at the relationship between total antioxidant capacity and type 2 diabetes in over 64,000 women followed for 15 years. They used total antioxidant capacity (TOC), an index that estimates antioxidant capacity from all dietary antioxidants.

Compared with women with the lowest TOC capacity, women with higher TOCs had a lower risk for type 2 ranging from 26-30% (2).

Foods and beverages that contributed the most to the TOC were fruit, vegetables, alcoholic drinks (wine) and hot beverages such as tea, chicory and hot chocolate – all known to have abundant levels of antioxidant compounds. The researchers had previous shown that coffee intake was associated with lower risk of type 2.

References

1. Fenwick EK, et al. Diet soft drink is associated with increased odds of proliferative diabetic retinopathy. Clin Exp Ophthalmol. Epub Feb. 23, 2018.
2. Mancini FR, et al. Dietary antioxidant capacity and risk of type 2 diabetes in the large prospective E3N-EPIC cohort. Diabetologia. 61:308–16, 2018.

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In the news: Sleeping Longer May Curb Sugar Intake; Can omega-3 Lower Glaucoma Risk?

Do Dietary Fats Impact Glaucoma Risk?

Poly-unsaturated fatty acids or PUFAs are fatty acids like the omega-6s (e.g. those from meats, dairy) and many vegetable oils) and omega-3s (e.g. those from oily fish and walnuts). Does our intake of these fatty acids impact the risk for glaucoma?

More studies are needed to answer this question, but previous research suggests that the type or amount of PUFAs may affect glaucoma risk. One study found lower levels of omega-3 fatty acids in glaucoma patients. Another linked a higher ratio of dietary omega-6 to omega-3 with increased glaucoma risk.

To shed more light on the possible relationship of PUFAs and this eye disease, UCLA researchers analyzed information on diet and glaucoma prevalence from 3,865 participants in the US National Health and Nutrition Examination Survey (1).

The study found that increased daily levels of the omega-3 PUFAs EPA and DHA were linked to significantly lower odds of having glaucoma.

Higher levels of total PUFAs, however, significantly raised glaucoma risk, which could be due to a high omega-6 to omega-3 ratio, the authors explained.

If these findings were confirmed by further research, the take home message would be to eat a good amount of omega-3 rich foods, while watching overall PUFA intake.

One strategy to achieve this might be to consume a Mediterranean style diet as it contains mono-unsaturated fats (MUFAs) like those in olive oil, and includes seafood ample in omega-3s.

Can Sleeping Longer Curb Sugar Intake?

Evidence increasingly links poor quality or too little sleep with weight gain, obesity and cardio-metabolic disease, which includes heart disease, stroke and type 2 diabetes. Studies show that insufficient sleep can increase appetite, particularly for carb-high calorie-rich snacks.

Researchers from the U.K. recently conducted a pilot randomized controlled trial to see whether increasing sleep time can impact nutrient intake among those who typically sleep for less than the recommended minimum of seven hours nightly (2).

One group received counseling on how to increase sleep that was personalized to each participant’s lifestyle (e.g. no caffeine before bedtime, establishing a relaxing routine, setting a bedtime, etc.). The control group was given no sleep intervention counseling.

Those in the counseled group were able to extend their sleep time – about 86% increased time spent in bed, half extended sleep duration (ranging from 52 to almost 90 minutes), and three participants achieved a week average within the recommended 7-9 hours nightly. No significant differences were seen in the control group.

Participants who received sleep advice also consumed 10 grams less of free sugars compared to levels at the study’s start. There was also a trend toward reduced intake of total carbohydrates, though it didn’t reach statistical significance. Free sugars were those added to foods by manufacturers, or in cooking at home as well as sugars in honey, syrups and fruit juice.

The results suggest that increasing time in bed for an hour or so longer may lead to healthier food choices. This further strengthens the link between short sleep and poorer quality diets that has already been observed by previous studies, according to the study’s lead investigator (3). The researchers are planning longer-term and more detailed studies in the future.

References

1. Wang YE, et al. Association of dietary fatty acid intake with glaucoma in the U.S. JAMA Ophthalmol. 136(2):141-47, 2018.
2. Haya K, et al. Sleep extension is a feasible lifestyle intervention in free-living adults who are habitually short sleepers: a potential strategy for decreasing intake of free sugars? A randomized controlled pilot study. Am J of Clin Nutr, Epub ahead of print, 2018.
3. King's College London. "Sleeping for longer leads to a healthier diet." ScienceDaily. January 9, 2018.

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In the news: Med Diet May Lower Prostate Cancer Risk; Med Diet and Men’s Sexual Health?

Med Diet May Lower Prostate Cancer Risk

The Mediterranean (Med) style diet offers a cuisine rich in flavors, colors and aromas. Ever-growing evidence from both controlled trials and observational studies has shown that this kind of eating pattern may help ward off heart attack, stroke, dementia and premature death. Spanish researchers now report that this way of eating may also help lower the risk of aggressive prostate cancer (1).

Investigators garnered dietary information from men with confirmed cases of prostate cancer (754) and 1,277 men without the disease who served as controls. They then analyzed the participants’ diets in terms of how well they adhered to three dietary patterns, and assessed the relationship of each eating style with prostate cancer risk.

The dietary patterns and their main included:
1) Med – rich in fish, olive oil, whole fruits, veggies, legumes (seeds and beans) and low in juices;
2) Prudent – low-fat dairy products, whole grains, fruits and veggies, and juices;
3) Western – dairy products, sodas, sweets, fast foods, sauces, processed meats and refined grains.

Sticking closely to the Med dietary pattern, rich not only in fruits and vegetables but also in fish, legumes and olive oil, lowered the risk of aggressive prostate cancer by about 1/3, and the likelihood of advanced stage cancer by about 1/2.

This association was not observed with the prudent pattern, which combines vegetables and fruits with low fat dairy products, whole grains and juices. These findings suggest that key features of the Med diet such as fish, legumes and olive oil are particularly important, and that eating fruits, veggies and whole grains – while also important – might not be enough.

While the data hinted that following a Western dietary pattern closely might increase the risk of more advanced tumors, the observation did not achieve statistical significance.

How Do Diets Impact Men’s Sexual Health?

To shed some light on this question, researchers reviewed the current literature on diet and dietary patterns and male sexual health. Thirteen studies on diet and erectile dysfunction and 15 studies on diet and testosterone levels were reviewed (observational studies and controlled trials). Studies analyzing the relation between diet and semen parameters also were reviewed – 13 studies, all observational(2).

The Med diet pattern was consistently associated with improvements in erectile function and an increase in testosterone levels. This makes sense as the Med diet emphasizes primarily plant-based foods (fruits, veggies, whole grains, legumes and nuts), and uses herbs and spices instead of salt to flavor dishes.

Many green leafy vegetables (kale, lettuce, spinach, cabbage, arugula and chard), as well as root vegetables (e.g. beets, carrots, potatoes, and ginger) contain high levels of nitrates. Nitrates become a source of nitric oxide, which dilates blood vessels and promotes blood flow. Increasing nitric oxide is how erectile dysfunction (ED) drugs work. Fruits and veggies are also a source of flavonoids, whose intake has been associated with reduced incidence of ED.

The review also found that overweight men who lost weight through low-fat, low-calorie diets seemed to have improved erectile function and testosterone levels. Weight loss in some obese and overweight men can favorably affect the enzyme (aromatase), helping convert estrogen to testosterone.

Several studies have shown that the Mediterranean diet can promote weight loss as well. The Western diet, meanwhile, was linked to lower semen quality.

More research is needed to fully establish the benefit of differing dietary patterns on men’s sexual health, according to the authors. In the meantime, the Med diet is shown to be an overall healthful way of eating.

References

1. Castello A, et al. Mediterranean dietary pattern is associated with low risk of aggressive prostate cancer. J Urology. 199:430-37, 2018.
2. La J, et al. Diet and men's sexual health. Sex Med Rev. 6:54-68, 2018.

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In the news: Spice it up in the New Year!

Spices Offer Flavor & Contribute to Health

A variety of spices – from near and afar – not only add pizazz to the dinner menu, but many contain compounds that contribute to our dietary antioxidant intake or that have anti-inflammatory actions. Two review articles (1,2) published in December highlight several culinary spices worth having in the cupboard – spices that add flavor, aroma and color, as well as potent antioxidant compounds.

Antioxidants can protect lipids and oils in food against oxidative degradation. When added to food, anti-oxidants control rancidity development, retard the formation of toxic oxidation products and help maintain nutritional quality of foods. Natural antioxidants contained in spices help to combat oxidative stress, which is caused by high concentrations of free radicals in cells and tissues.

Studies have shown that spices and herbs such as rosemary, sage, and oregano – go to spices for Christmas turkeys and dressing – are excellent sources of antioxidants with their high content of phenolic or bioflavonoid compounds. Typically flavonoids and phenolic acids are the main phenolics in spices that possess antioxidant activity. They may include flavonoids such as apigenin, luteolin, quercetin and kaempferol. The highest amounts of flavonoids have been found in parsley, oregano, celery, saffron, dill, and fennel.

Rosmarinic acid is also a dominant phenolic compound responsible for the antioxidant capacity of many spices, including rosemary, oregano, and thyme, but also cumin and cinnamon.

The Cinnamon that you may have used to garnish holiday eggnog, comes from the inner layer of bark derived from many varieties of evergreen trees that belong to the genus Cinnamomum. Most cinnamon comes from Indonesia; some from Siri Lanka, China and other countries. Cinnamon contains various antioxidant compounds that are routinely used in a traditional system of medicine to treat chronic diseases such as cardiovascular diseases and diabetes in various regions of the world.  

Supplemental extracts of the common species cassia cinnamon containing a polyphenol (methylhydroxy-chalcone polymer) seem to improve insulin sensitivity and increase uptake of glucose (sugar) from the blood stream. However, the results of clinical trials have been inconsistent: some have shown improvement in blood glucose levels or insulin sensitivity or in people with type 2 diabetes or insulin insensitivity, while others have not.

Derived from the flower of Crocus sativus, the crimson colored spice saffron is often used to add color and flavor to rice dishes. First cultivated in or near Greece, most saffron is now grown in Iran. Saffron contains carotenoids including zeaxanthin, lycopene and alpha- and beta-carotene, as well as compounds such as crocetin, crocins, and safranal. Some research suggests that saffron supplementation may improve symptoms of depression in adults, though larger clinical trials with long-term follow-ups are needed before firm conclusions can be made regarding saffron for treating depressive symptoms (3).

One of the rising stars in the world of spices is turmeric or Curcuma longa, a member of the ginger family. With it’s bright yellow colored polyphenol component curcumin, this spice is found in Indian curry dishes, consumed as a tea in Japan, and has been traditionally used in Asian countries as a medical herb due to its antioxidant, anti-inflammatory and anti-microbial properties.

Curcumin research has been gaining scientific attention, with preliminary studies suggesting that it may be helpful in osteoarthritis, that it may aid performance on attention and working memory tasks, or be helpful in reducing depressive symptoms. Curcumin is poorly absorbed, but recent technical advances have resulted in supplemental curcumin with enhanced bioavailability. So expect more published research on curcumin in the coming year.

References

1. Yashin A, et al. Antioxidant activity of spices and their Impact on human health: Review. Antioxidants. 6, 70; 2017.
2. Hewlings SJ and Kalman DS. Curcumin: A Review of Its’ Effects on Human Health. Foods. 6, 92; 2017.
3. Shafiee M, et al. Saffron in the treatment of depression, anxiety and other mental disorders: Current evidence and potential mechanisms of action. J Affect Disord. [Epub ahead of print] Nov, 2017

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In the news: Zeroing in on Magnesium: Recent Research

Multiple Roles of Magnesium

Magnesium is required by more than 300 enzyme systems that regulate many biochemical reactions in the body. So it’s no wonder that magnesium plays a role in many diverse processes: It helps regulate muscle and nerve function, as well as blood pressure and blood sugar levels. It is also needed to make protein, DNA, and is involved in the formation of bone.

While surveys show that most of us recognize the importance of magnesium, many - about 50% of Americans-- aren’t consuming an adequate amount of this mineral. The recommended daily magnesium intake for adults is 420 mg (men) and 320 mg (women). Good food sources include green leafy vegetables, beans, nuts, seeds, and whole grains.

Several observational studies published in the last few months, underscore the potential benefit of getting more magnesium-containing foods in our daily diet.

More Magnesium, Stronger Muscles & Bones

British researchers set out to investigate the relationship between dietary magnesium and skeletal muscle and bone health by analyzing data from over 156,500 men and women participating in the UK Biobank Study (1).

The investigators found that those consuming the most magnesium had better grip strength (1.1% men, 2.4% women) and higher bone mineral density (2.9% men, 0.9% women) compared to those consuming the least. Compared to the lowest intake group, the higher magnesium intake group also had greater fat free mass as percent of body weight (3% men, 3.6% women; fat free mass refers mainly to lean muscle mass and bone).

While these differences may sound modest, they are clinically important considering the annual losses of bone mineral density and skeletal muscle that occur with aging. The participants in this study ranged from 39 to 72 years old. Among men over the age of 60 with high magnesium intake, grip strength was about twice that of younger men. This study strongly suggests, though doesn’t prove, that eating adequate amounts of magnesium may be protective of muscle and bone in middle age and as we grow older.

In a related study (2), UK researchers explored the relationship between magnesium intake (from food and supplements) and bone fracture risk in a large group of older men and women participating in the Osteo-arthritis Initiative over a follow-up period of 8 years.

Compared with the lowest magnesium intake, the highest intake was associated with a 62% (women) and 53% (men) reduced risk of fracture. The findings are promising since stemming loss of bone mineral density doesn’t always translate to lower fracture risk. Clinical trials testing magnesium’s ability to reduce fractures are warranted, according to the authors.

Magnesium is required for insulin secretion by the pancreas, and for tissues to respond to insulin by taking up glucose (sugar) from the blood stream.

Magnesium, Glycemic Index & Diabetes

Magnesium is required for insulin secretion by the pancreas, and for tissues to respond to insulin by taking up glucose (sugar) from the blood stream. Researchers from Tufts and Harvard Universities analyzed data from three large studies, which included more than 200,000 people followed for 28 years. They found higher magnesium intake to be associated with a 15% lower risk of type 2 diabetes (3).

That association was even stronger in those who ate high glycemic index (GI) diets- diets low in fiber and high in processed carbohydrates such as white flour and sugary foods and beverages.

Taken together, these studies offer a compelling reason to make magnesium-rich foods a priority in our diets.

References

1. Welch AA, et al. Dietary magnesium may be protective for aging of bone and skeletal muscle in middle and younger older age men and women: Cross-sectional findings from the UK Biobank Cohort. Nutrients; 9:1189, 2017.
2. Veronese N, et al. Dietary magnesium intake and fracture risk: data from a large prospective study. Br J Nutr; 117:1570-76, 2017.
3. Hruby A, et al. Magnesium Intake, Quality of Carbo-hydrates and Risk of Type 2 Diabetes: Results From Three U.S. Cohorts. Diabetes Care 40:1695-1702, 2017.

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In the news: Salad Oils Aid Nutrient Absorption; Low Vitamin D Early & Later in Life

Oil in Salad Dressing Helps Absorb Nutrients

Only 9% of Americans eat the 2-3 cups of vegetables recommended daily, and many people consume their vegetables in the form of lettuce and vegetable salads for lunch or dinners, according to consumer surveys.

While the calorie-conscious often avoid using salad dressing, a new study (1) has found that the added oils from dressings enhance the absorption of essential nutrients from salads - namely vitamins E, K, alpha and beta carotene, lutein and lycopene.
 
In the study, each participant consumed five test salads with equivalent vegetable amounts (spinach, romaine lettuce, carrots and cherry tomatoes), but each salad had added dressing with different amounts of soybean oil (0, 2, 4, 8 or 32 g).

The researchers found that nutrient absorption was far lower without any added oil, while the maximum absorption for most nutrients occurred at the 32 g level- a little less than 2 tablespoons of oil.

Soybean oil was tested in this study because it’s the predominant oil used in making bottled salad dressings. However, a previous study showed that oils like canola and olive oil are efficient at promoting the absorption of vegetable’s nutrients as well. The bottom line is that you don’t need to drench a salad with dressing- using a tablespoon or so of olive oil with some vinegar to dress a salad can improve the body’s absorption of important fat-soluble nutrients.

Poor vitamin D Status May Affect Young & Old

Two recently published observational studies suggest that vitamin D deficiency may have consequences in the elderly at risk of heart failure, and in children at risk of type-1 diabetes.

Heart failure, one of the most common reasons people age 65 and older are hospitalized, means that the heart isn’t pumping efficiently enough to meet the body’s need for blood and oxygen. Brazilian university researchers recently report an association between vitamin D deficiency and a higher risk of heart failure in a study of elderly cardiac patients (2). More than half of the 137 elderly patients studied were at risk of heart failure, and that risk was strongly associated with vitamin D deficiency.

About 65% of the patients were deficient based on having blood vitamin D levels less than 30 ng/ml- a higher value than the 20 ng/ml that is more widely used to define deficiency.
 
vitamin D deficiency was associated with a 12-fold higher risk of heart failure. This was considerably higher than the risks associated with being obese or having cardiac arrhythmia, each of which was linked to about a 4-fold increase heart failure risk.

This is a small study, and one that does not prove cause and effect. However the association has been noted in a few other studies, and the researchers indicate the need for clinical trials with vitamin D supplementation in older patients with heart failure.

In the other vitamin D-related study (3), children with a higher genetic risk for developing type-1 diabetes were checked regularly from infancy to early childhood, and followed in later years. The participants were recruited from the US and across Europe.

vitamin D levels were determined and researchers looked for antibodies that are detected when insulin-producing islet cells of the pancreas are attacked by the body’s immune system. Called “islet auto-immunity,” the antibodies are considered a precursor to type-1 diabetes.

Comparing vitamin D levels in the early years for those that developed islet autoimmunity with those that did not, showed significantly lower blood levels in those who developed the type-1 precursor. Once again, intervention studies are needed to determine whether vitamin D is a factor in preventing type-1 diabetes. 

References

1. White WS, et al. Modeling the dose effects of soybean oil in salad dressing on carotenoid and fat-soluble vitamin bioavailability in salad vegetables. Am J Clin Nutr 106:1041-51, 2017.
2. Porto CM, et al. Association between vitamin D deficiency and heart failure risk in the elderly. ESC Heart Failure. Epub ahead of print, Aug 2017.
3. Norris JM, et al. Plasma 25-hydroxyvitamin D concen-tration and risk of islet autoimmunity. Diabetes. Epub ahead of print, Oct 2017.

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In the news: Avocados for the Mind & Vision; Flavonoids & Healthy Body Composition

More Avocados For Good Vision & Cognition

The September issue of Staying Healthy focused on research exploring whether lutein and zeaxanthin may support brain function in older people and children. Avocados were also mentioned as a good dietary source of these carotenoids.

The body selectively concentrates lutein from the foods we consume into the eye’s macula and into brain tissue. Studies have shown that lutein levels in the macula (measured via macular pigment density or MPD) reflect lutein levels in the brain. So MPD is considered a biomarker for brain concentrations of lutein.

As follow-up, a new study from Tufts University reports that daily consumption of avocados increases MPD, and that those increases appear to be related to better cognitive performance (1).

In the trial, older participants were randomly assigned to a group eating one avocado daily or to a group consuming one cup of chickpeas or one potato (neither of which contain lutein) each day. MPD was measured and cognitive testing was conducted at the study’s start, and at three and six months.

Only the avocado group had a significant increase in MPD at the end of the study. That group also fared better on tests of sustained attention. The increases in MPD seen in the avocado group were related to improved scores on tests of working memory and efficiency in approaching a problem.

Both groups, however, saw improvements in tests for memory and spatial working memory. The researchers suggest this finding might be a result of increasing familiarity with these tests over the course of the study.

The avocados provided only ½ milligram of lutein daily- far less than the amounts of lutein typically supplemented in other studies. Yet the avocados appeared to be quite efficient in increasing lutein levels in blood and in the macula.

The study authors suggest that this efficiency could be due to the monounsaturated fats in avocados. Mono-unsaturated fat from avocados has been reported toincrease HDL cholesterol- important because lutein is transported in the body by HDL molecules. In the present study, avocado intake resulted in higher blood levels of lutein that were significantly related to increases in HDL.

Avocados complement other rich sources of lutein like green leafy vegetables (e.g. spinach and kale) and egg yolks. The avocado, a fruit, provides substantial amounts of vitamins, minerals and other nutrients with relatively few calories.

Flavonoids Linked to Body Fat Accumulation

Increasing evidence suggests that eating flavonoids from plant-based foods such as fruits, vegetables, tea, wine, and chocolate, may be beneficial for weight maintenance. Now for the first time, researchers report that flavonoid-rich foods may affect body fat and where it’s distributed in the body (2).

The study was conducted in the UK and included over 2700 healthy identical twins, all women. Any differences between identical twins are due to factors other than genetics.

In brief, higher consistent intake of a number of flavonoids, including anthocyanins (e.g. blueberries,
grapes, and wine), flavan-3-ols (e.g. apples, tea and wine), flavonols (e.g. onions, tea, and pears), and proanthocyanidins (e.g. apples, cocoa), were associated with lower body fat, and not due to shared genetic and common environmental factors including physical activity and intake of sugar-laden beverages.

It was striking that twins with the highest intake of many of these flavonoids had less fat accumulation in the lower torso around the stomach and abdomen than their co-twins. Fat in this area is particularly unhealthy as it’s associated with insulin resistance, the metabolic syndrome and higher risk of cardiovascular disease.

References

1. Scott AM, et al. Avocado consumption increases macular pigment density in older adults: A randomized, controlled trial. Nutrients; 9(9):919, 2017.
2. Jennings A, et al. Higher dietary flavonoid intakes are associated with lower objectively measured body composition in women: evidence from discordant mono- zygotic twins. Am J Clin Nutr; 105:626-34, 2017.

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In the news: Higher Magnesium Intake Lowers Type 2 Risk in Those with High GI Diet

Magnesium, Glycemic Index & Disease Risk

As the global prevalence of type 2 diabetes increases, so will the number of people with diabetic retinopathy and other micro-vascular complications of the disease. Prevention of diabetes by addressing modifiable risk factors such as obesity, poor diet, and physical inactivity is paramount, although achieving sustainable behavior change is often difficult.

Based on the newly published findings of Tufts and Harvard researchers, one fairly simple step toward type 2 risk reduction may be to ensure adequate intake of magnesium. Recognized as a shortfall nutrient in the Scientific Report of the 2015 Dietary Guidelines Advisory Committee, nearly 50% of the US population has inadequate magnesium intake.

Hypomagnesemia tends to be more pronounced in pre-diabetes, insulin resistance or diabetes. Low serum levels have been associated with increased risk of prediabetes and diabetes via insulin resistance pathways. Magnesium is integral to insulin secretion and sensitivity. It’s been shown that low levels of magnesium impair insulin function, while the compensatory overproduction of insulin that occurs with insulin resistance depletes magnesium levels.

The new research, which combined cohorts from three large studies followed for 28 years, found that higher magnesium intake is associated with lower risk of type 2, especially in those consuming high glycemic index (GI) diets – diets low in fiber and high in processed carbohydrates such as white flour and sugar. The high GI diet is a common dietary pattern in the US, and one that has been associated not only with the risk of diabetes, but with cataract and early AMD as well.

Design and Methods

This analysis used data from the Nurses’ Health Study (n= 69,176), the Nurses’ Health Study 2 (n= 91,471) Health Professionals’ Follow-Up Study (n= 42,096). In these studies, dietary intake was assessed from food frequency questionnaires every 4 years. Magnesium intake was from food and supplements. Type 2 diabetes was ascertained by biennial and supplementary questionnaires.

Multivariate hazard ratios of magnesium intake and incident diabetes were calculated and adjusted for multiple factors including age, BMI, family history of diabetes, physical activity, smoking, hypertension, hypercholesterolemia, energy intake, trans fatty acids, and other factors. The joint associations of magnesium and carbohydrate quality on diabetes risk were also considered.

Results

Over 28 years of follow-up, 17,130 incident cases of type 2 diabetes were documented.

In pooled analyses across the three cohorts1, those with the highest magnesium intake had 15% lower risk of type 2 diabetes compared with those with the lowest
intake (pooled multivariate HR in quintile 5 vs. 1:0.85 [95% CI 0.80–0.91], P < 0.0001).

Higher magnesium intake was more strongly associated with lower risk of type 2 diabetes among participants with high GI or low cereal fiber than among those with
low GI or high cereal fiber (both P interaction <0.001).

Conclusion

Higher magnesium intake is associated with lower risk of type 2 diabetes, especially in the context of lower carbohydrate-quality diets.

Comments

These results are consistent with a large body of observational literature on the beneficial role of magnesium on type 2 diabetes risk. A recent meta-analysis of 25 prospective cohort studies, for example,
indicated a linear dose-response relationship between magnesium intake and type 2 diabetes, with an 8–13% lower risk per 100 mg/day increase in intake. The recommended daily magnesium intake for adults is 420 mg (men) and 320 mg (women). Good food sources include green leafy vegetables such as spinach, legumes, nuts, seeds, and whole grains.

References

1. Hruby A, et al. Magnesium Intake, Quality of Carbohydrates, and Risk of Type 2 Diabetes: Results From Three U.S. Cohorts. Diabetes Care 40:1695–1702, 2017.

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In the news: Can Lutein Benefit the Brain in Children, the Middle-Aged & Older?

Can Carotenoids Help the Brain Stay Agile?

One consequence of growing older appears to be a loss of some aspects of our cognitive abilities – a loss that can be measured as early as middle age. Brain researchers are attempting to better understand how cognitive decline occurs with age.

Since people vary widely in age-related cognitive function, some researchers have wondered whether one’s diet could be driving some of these differences. Some evidence, for instance, suggests that dietary carotenoids might be a factor in slowing cognitive decline in older individuals.

Measuring amounts of the carotenoids lutein and zeaxanthin concentrated in the eye’s macula (via macular pigment optical density or MPOD) may be one way of testing how diet might influence the brain. That’s because MPOD levels have been found to reflect dietary intake of carotenoids and brain concentrations of lutein, the main carotenoid in human brain tissue.

Researchers from the University of Illinois at Urbana–Champaign, recently studied 60 young to middle-aged adults (25-45 years old) to see whether there was a notable difference in how participants with higher or lower lutein levels performed cognitive control tasks (1).

Cognitive control refers to the brain’s flexibility in adapting to changes when processing information. One of the control tasks performed reflects the mind’s ability to maintain attention and tune out distractions that aren’t relevant to the task at hand.

Electrical brain activity was recorded during performance of the tasks, and MPOD was measured.
The investigators found that MPOD was related to both age and the P3 wave – the specific electrical brain activity that occurs during decision making.
In general, younger study subjects had P3 wave amplitudes that were larger than older subjects.

The most interesting finding, however, was that older participants with higher MPOD levels had P3 wave amplitudes that were similar to their younger counterparts.

According to the authors, “the protective role of carotenoids within the central nervous system [brain] may be evident during early and middle adulthood, decades prior to the onset of older age.” Eating more lutein and zeaxanthin-rich food is a good habit to start early in life rather than waiting until old age to up our intake.

MPOD Levels Linked to Cognition in Kids

The same research team also explored the connection between the eye and brain in childhood – a critical period for carotenoid accumulation in the brain.

The team looked at 49 children, average age of 8 1/2, who participated in a widely regarded clinical trial (the FITKids Randomized Controlled Trial on Executive Control and Brain Function).

As with the previous study in 25-45 year olds, MPOD levels were measured and electrical brain activity (P3 wave) was recorded as the kids performed cognitive tasks (2).

MPOD was associated with more accurate task performance and P3 wave amplitude. The results suggest that children with higher MPOD may respond to cognitive tasks more efficiently.

While the results of both studies hold great promise, future clinical trials are needed to determine whether better intake of lutein can influence mental function in the young as well as help counter some of the subtle cognitive changes that come with age.

Meanwhile, we know that dietary carotenoids play a vital role in vision. So it makes good sense to eat more leafy veggies like kale and spinach, eggs, and avocados – one of the richest fruit sources of lutein.

References

1. Walk AM, et al. The role of retinal carotenoids and age on neuroelectric indices of attentional control among early to middle-aged adults. Front Aging Neurosci 9:183, 2017.
2. Walk AM, et al. From neuro-pigments to neural efficiency: The relationship between retinal carotenoids and behavioral and neuroelectric indices of cognitive control in childhood. Inter J Psychophysiol. 118:1-8, 2017.

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In the news: Combating Chronic Inflammation: Omega-3, Lutein, Olive Oil

What is Chronic Inflammation?

Acute or immediate inflammation is a necessary and normal part of the healing process. Without it, infections and injuries would never heal. But chronic or long term inflammation can eventually lead to some conditions including rheumatoid arthritis, atherosclerosis, and periodontitis. It’s also known that chronic inflammation plays an important role in heart disease, although researchers still don’t clearly understand what drives that inflammation in the first place.
 
However, studies continue to uncover factors that can contribute to chronic inflammation. Insufficient or poor quality sleep, for instance, has been shown to raise markers of inflammation. Overweight and obesity too, are associated with higher levels of inflammatory markers – levels that tend to fall when weight is shed.  

Research into dietary strategies that can quiet, perhaps even resolve, chronic inflammation is also ongoing in such diverse areas as obesity, cardiovascular, and bone health.

Omega-3s Dampen Inflammation in Weight Loss

According to recent findings, the ability of weight loss to impact chronic low-grade inflammation may be bolstered by a greater intake of omega-3 fatty acids (1).

Women with obesity on a calorie-controlled diet were randomly assigned to receive supplemental omega-3s (1.8 g DHA + EPA) or placebo daily for 3 months. Both groups lost weight and body fat, though the women in the omega-3 group had significantly decreased concentrations of several important inflammatory markers, including C-reactive protein.

The omega-3 group also displayed an increase of compounds called SPMs, or pro-resolving mediators that have anti-inflammatory and cell-protecting actions. SPMs, like resolvins and protectins, are made from the omega-3 fatty acids DHA and EPA when triggered. According to the researchers, the higher levels of SPMs, especially those derived from DHA, indicate that they may be helping to limit or turn off the low-grade inflammation present in these women. The take home message: when counting calories for weight loss, make room in the calorie count for DHA/EPA-rich fatty fish like salmon, sardines and tuna.

Lutein May Help Combat Artery Inflammation

University researchers found that higher blood levels of one carotenoid, lutein, out of the many colorful carotenoid compounds in fruits and veggies, correlated with a lower level of an inflammatory marker (IL-6) in patients with coronary artery disease (CAD) (2). According to the authors, these patients were receiving gold standard care for their disease, yet many of them still had persistent inflammation. Many also had lower lutein blood levels.

The team then showed that immune cells that secrete the IL-6 marker absorb and store lutein. The greater content of lutein in these cells reduced IL-6 production.
The team plans to test whether increasing lutein intake has a beneficial effect on the immune system in CAD. The take home message: CAD patients, along with those looking to maintain eye health, should consume lutein-rich green leafy veggies – spinach, collards and kale.

Inflammation, Olive Oil & Risk of Bone Loss

Inflammation as a potentially important factor in bone health is gaining attention, with researchers observing that participants in the large Women’s Health Initiative eating healthier, “anti-inflammatory” diets did not lose bone as quickly as those with high-inflammation diets.

Investigators of the PREDIMED study have also found that among an older Mediterranean (Med) population at high risk for CVD, greater consumption of extra virgin olive oil was associated with a 51% reduction in risk of fractures3. Olive oil, one of the key foods of the Med diet, contains phenolic compounds with anti-inflammatory activity. The take away: olive oil may be part of a healthy anti-inflammatory diet along with fruits, veggies, fatty fish and others for healthy bones.

References

1. Polus A, et al. Omega-3 fatty acid supplementation influence the whole blood transcriptome in women with obesity, associated with pro-resolving lipid mediator production. Biochim Biophys Acta 1861:1746-55, 2016.
2. Chung RWS, et al. Lutein exerts anti-inflammatory effects in patients with coronary artery disease. Athero-sclerosis. 262:87-93, 2017.
3. Gavilan-Garcia J, et al. Extra virgin olive oil consumption reduces risk of osteoporotic fractures. Clin Nutr. [Epub ahead of print], 2017.

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In the news: Vitamin K Linked to Cataract Risk; Best Time to Take Probiotics?

Can Vitamin K Intake Influence Cataract Risk?

The answer to that question is not yet known, but a new observational study has linked higher intake of vitamin K1 with a lower risk of cataract (1).

While the underlying processes of cataract formation are still unclear, growing evidence suggests a potential role of oxidative stress and inflammation.

Vitamin K1 is best known for its role in blood clotting and bone metabolism. However, it may also play a role keeping calcium from accumulating in artery walls and has been shown to have anti-inflammatory activity.

To investigate whether vitamin K1 could potentially play a protective role in the eye’s lens, researchers looked at the diets of 5,860 older individuals who took part in the Prevención con Dieta Mediter-ránea clinical trial or PERIMED Study and the development of cataracts among the participants.

After a follow–up of nearly 6 years, a total of 768 new cataracts were documented. The highest dietary intake of vitamin K1 was associated with a 29% lower risk of cataract compared to the lowest intake of the vitamin.

This is the first time vitamin K1 has been linked to cataract risk in humans, so further research is required to validate this observation. However, the role of vitamin K1 does appear to be expanding, so keep eating good sources of this vitamin: green leafy vegetables such as lettuce, broccoli, kale, Swiss chard, parsley and spinach.

Is There a “Best” Time to Take Probiotics?

Probiotics are healthful bacteria that are either the same as or very similar to bacteria that normally colonize the human body. These bacteria form diverse, complex and large communities– their numbers in the digestive tract alone surpass the number of total cells in the body.

Probiotics research has exploded over the last few years, with studies looking at the potential effects of specific bacterial species and strains on various health parameters such as digestion, immunity and mood.

Use of supplemental probiotics is on the rise as well, leading to the common question: When should they be taken to better the odds of surviving passage through the stomach?

Bacteria are vulnerable to stomach acidity. Taking them without having eaten would mean a shorter stay in the stomach, but with a higher level of acidity. Taking them with a meal results in the bacteria staying in the stomach longer, though stomach acidity gradually decreases with the addition of food.

The results of a new and preliminary study (2) suggest that the timing of probiotic consumption is not that important. In the study, healthy participants were randomly assigned to take a probiotic supplement 30 minutes before or 30 minutes after breakfast. (The probiotic consisted of 4 billion colony forming units or CFUs of Bifidobacteria longum species BB536 strain combined with 1 billion CFUs of Lactobacillus rhamnosus species HN001 strain).

At the end of one month, the difference in timing did not appear to influence the number of participants with detectable levels of the bacterial strains consumed– both groups had an increase in bacterial load. The groups also displayed a beneficial change in the composition of intestinal bacteria. The probiotic was associated with reductions in bacterial families that have been linked to obesity or to the risk of developing inflammatory bowel disease.

More and larger studies that examine the best timing for probiotic consumption are warranted to confirm these findings.

References

1. Camacho-Barcia ML, et al. Association of Dietary Vitamin K1 Intake With the Incidence of Cataract Surgery in an Adult Mediterranean Population: A Secondary Analysis of a Randomized Clinical Trial. JAMA Ophthalmol. 135:657-61, 2017.
2. Toscano M, et al. Effect of Lactobacillus rhamnosus HN001 and Bifidobacterium longum BB536 on the healthy gut microbiota composition at phyla and species level: A preliminary study. World J Gastroenterol. 23: 2696–704, 2017.

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In the news: Olive Oil Linked to Lower AMD Risk; Can Lutein / Zeaxanthin Reduce Stress?

Regular Olive Oil Intake May Lower AMD Risk

Following the Mediterranean diet has been linked to better health, including a reduced risk of heart disease, slower cognitive decline, and a lower risk of age-related macular degeneration (AMD). The health benefits of this diet have been attributed, in part, to one of its key components, olive oil.

The Alienor Study is a study on eye diseases in a French population of older individuals. Researchers recently looked at the associations between olive oil use and AMD prevalence in 654 Alienor Study participants (1).

They measured how frequently the participants consumed various dietary fats and oils and categorized them by ‘no use’ and ‘regular use’. Using retinal photographs, participants were divided into three groups: no AMD, early AMD, and late AMD.

After adjusting for other factors that could affect AMD risk, they report that regular use of olive oil was significantly associated with a decreased risk of late AMD. Regular users were 56% less likely to have late stage AMD. No associations were found with olive use and early AMD.

The Alienor findings are similar to those of an earlier Australian study (2) of over 6,700 people, where olive oil intake was also linked to lower late AMD prevalence.

Besides its mono-unsaturated fatty acids (MUFAs), olive oil is a rich source of polyphenols with antioxidant and anti-inflammatory actions – compounds with tongue-twisting names like oleuropein (o-lura-pene), and oleocanthal (oleo-canthal).

Since a number of studies have reported seeing no association of MUFAs with AMD risk, the researchers suspect that the apparent protective effect of olive oil consumption they observed may be due to olive oil’s polyphenols.

Can Lutein & Zeaxanthin Reduce Stress?

If you’ve eaten some green leafy vegetables today, such as kale and spinach, you’ve consumed a good daily dose of the eye-healthy carotenoid lutein. lutein is especially concentrated in the macular region of the eye’s retina, where it is believed to protect against harmful blue light, oxidative damage, and AMD.

It has recently become clear that the human brain also preferentially accumulates lutein, and that the concentration of lutein and zeaxanthin in the macula (measured by MPOD) appears to reflect the content of these carotenoids in the brain. MPOD may, in fact, be linked to cognitive function. For example, low MPOD has been associated with lower cognitive performance in older individuals.

A new report suggests that supplemental lutein and zeaxanthin isomers may reduce psychological stress and improve measures of emotional health (3). In the 12-month long double-blind trial, 59 young healthy adults were assigned to receive either placebo, high dose lutein with zeaxanthin, or about half the dose of these carotenoids.

At the study’s start, MPOD correlated with measures of stress – Beck’s anxiety scores, serum cortisol, and psychological stress scores. Supplementation with lutein and zeaxanthin isomers significantly reduced stress, serum cortisol levels, and improved symptoms of suboptimal emotional and physical health at the trial’s conclusion.

There was no difference in results between the low dose group (a little over 10 mg of lutein and 2 mg zeaxanthin isomers) and the high dose group (about double the dose). The increase in MPOD over the study was virtually identical in both groups. More research is needed to confirm these preliminary findings.

References

1. Cougnard-Grégoire A, et al. Olive oil consumption and age-related macular degeneration: The Alienor Study. PLoS ONE. 11(7): e0160240, 2016.
2. Chong EW, et al. Fat consumption and its association with age-related macular degeneration. Arch Ophthalmol. 2009; 127:674–80, 2009.
3. Stringham NT, et al. Supplemention with macular carotenoids reduces psychological stress, serum cortisol, and sub-optimal symptoms of physical and emotional health in young adults. Nutr Neurosci. Epub  Feb. 15, 2017.

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In the news: Vitamin D and Statin Use; Low maternal vitamin E & Asthma

Vitamin D and Statin Use

Statins, prescribed to lower cholesterol and the risks of heart attacks and strokes, is one of the most widely used drugs in the U.S. For those who take statins, a series of studies suggests that maintaining sufficient levels of vitamin D is important.

Results of the most recent study indicate that people may need slightly more vitamin D to raise blood levels when they’re taking a statin (1). Researchers reviewed clinical trials in which supplemental vitamin D was given to people 60 and older who had low levels of this vitamin. They found that the response to vitamin D was about 21% lower in statin users versus non-users over a 12 month period.

Earlier research conducted in China reveals that statins work better when vitamin D levels are sufficient (2). In this 6-month placebo controlled trial, people with elevated cholesterol, and already being treated with a statin, saw a decrease in total and LDL cholesterol as well as triglycerides. Improvements in blood lipid levels were greatest in the nearly 75% of participants who were either vitamin D deficient (blood levels below 20 ng/mL) or marginally deficient (levels between 20 and 30 ng/mL).

Other investigations report that the chance of developing statin-related side effects may be lessened by maintaining better vitamin D levels. In one study of statin users (3), those without myalgia (muscle pain) had an average vitamin D level of about 35 ng/mL compared to an average level of 28 ng/mL in those experiencing myalgia, a potential side-effect of statins.

Another potential side effect of statins is that they can reduce the improvements in cardiorespiratory fitness that are normally gained with exercise, and they can disrupt energy-producing mitochondria in muscle cells. Adequate vitamin D may help offset these effects.

In one study (4), vitamin D deficient type 2 diabetics performed moderate aerobic exercise and were randomized to receive a statin, or a statin plus a high dose of vitamin D once weekly, or only vitamin D each week. Cardiorespiratory fitness decreased by 8.4%

after 12 weeks of statin therapy only, while the addition

of vitamin D blunted that decline in fitness to 0.6% and improved skeletal muscle mitochondrial content. vitamin D alone also increased cardiorespiratory fitness.

While it isn’t wise to take the very high amounts of vitamin D tested in the last study, it does make sense for those on statins to ensure that their vitamin D blood levels are sufficient based on the current evidence.

Vitamin E During Pregnancy & Asthma Risk

The February 2017 issue of Staying Healthy featured a study showing that pregnant women who received omega-3 fatty acids gave birth to children less likely to develop asthma. A new study (5) suggests that low vitamin E levels in mothers may also increase the risk for asthma in their children.

The investigators followed 652 children and their moms for the first two years of the children’s lives. The two main forms of vitamin E in the body, alpha and gamma vitamin E, were measured in the blood of the mothers post-pregnancy. Both vitamin forms had previously been shown to decrease lung inflammation in both animals and humans.  The results of the study show that children whose mothers had low blood levels of the alpha vitamin E form were more likely to suffer from wheeze and require asthma medications. Research is now needed to see whether improving maternal blood levels of alpha vitamin E can cut the risk of asthma in their children.

References

1. Bischoff-Ferrari HA, et al. Statin use and 25-hydroxyvitamin D blood level response to vitamin D treatment of older adults. J Am Geriatr Soc. Epub ahead of print, Feb. 2017.
2. Qin XF, et al. Effects of vitamin D on plasma lipid profiles in statin-treated patients with hypercholesterolemia: A randomized placebo-controlled trial. Clin Nutr. 34:201-6, 2015.
   3. Michalska-Kasiczak M, et al. Analysis of vitamin D levels in patients with and without statin-associated myalgia - a systematic review and meta-analysis of 7 studies with 2420 patients. Int J Cardiol. 178:111-16, 2015.
3. Singla M, et al. Vitamin D supplementation improves simvastatin-mediated decline in exercise performance : A randomized, double-blind, placebo-controlled study. J Diabetes. Accepted manuscript online: 24 February 2017.
4. Stone CA. American Academy of Allergy, Asthma & Immunology (AAAAI) 2017 Annual Meeting. Abstract 263. Presented March 4, 2017.

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In the news: Foods & Rheumatoid Arthritis; Impact of Poor Diet on Cardiometabolic Deaths

Certain Foods May Affect Arthritis Symptoms

Rheumatoid arthritis i(RA) is an autoimmune disease that usually requires the use of medications to calm joint inflammation. However, many patients ask their doctor whether dietary changes can also help in controlling their RA symptoms.

In fact, a number of small trials have reported some benefit for high-dose omega-3 fatty acids, fasting, and eating Mediterranean-type or vegetarian diets.

There has also been a popular focus on foods categorized as “inflammatory” and “anti-inflammatory”. To explore this idea further, Harvard researchers surveyed 300 RA patients to learn if specific foods affect their RA symptoms (1). The patients, all with longstanding disease, were asked whether they consume a list of 20 foods popularly thought to affect inflammation, and whether these foods make their RA symptoms better, worse, or unchanged.

Nearly one-quarter of those responding said foods affect their RA. Blueberries and spinach topped the list of foods most often reported to improve RA symptoms, while sugary sodas and desserts were most often said to worsen symptoms.  There was no difference in response based on the type of medication being used to treat the disease.

Most survey respondents said that exercising regularly helped reduce symptoms. Those who reported that foods impacted their disease were also more likely to report that other factors improve their RA – namely getting a good night’s sleep, keeping room temperatures warm, and using vitamin / mineral supplements.

They study’s authors said that, while they cannot draw firm conclusions based on this survey, it is very possible that some foods have anti-inflammatory effects. A recent randomized trial in children with juvenile rheumatoid arthritis (2), for example, found that blueberry juice plus an anti-arthritis drug (etanercept), was better than the drug alone in improving the disease and reducing a blood marker of inflammation.

In addition, recent work has shown that greater intake of sugar-sweetened beverages is associated with an increased risk for developing RA in women (3).

The authors conclude that more studies of how specific foods and eating patterns affect in RA disease activity are needed, especially in light of the potent drug therapy used to treat RA.

45% of Deaths from Heart Disease, Stroke & Type 2 Diabetes Linked to Poor Diet

We all know that what we eat—and don’t eat—can influence our risk of cardiometabolic diseases (heart disease, stroke, and type 2 diabetes).  But a new study from Tufts University published in the Journal of the American Medical Association, reveals just how critical a role diet really plays (4).

Looking at data from many sources (e.g. National surveys, clinical trials, meta-analyses and National Center for Health Statistics), the research team evaluated the association between 10 foods / nutrients and cardiometabolic deaths occurring in 2012.

There were over 700,000 such deaths in that single year, and an estimated 45% of them were linked to eating too much or too little of those 10 dietary factors.   

The greatest number of diet-related cardiometabolic deaths was associated with eating too much salt, processed meats and sugary drinks, and not enough nuts and seeds, fruits and vegetables, seafood (omega-3 fats) and whole grains compared to optimal amounts. An accompanying editorial stated that the findings of this study appear correct--a substantial portion of these deaths are linked to poor diet.

References

1. 1. Tedeschi SK et al. Diet and rheumatoid arthritis symptoms: Survey results rrom a rheumatoid arthritis registry. Arthritis Care Res; Published online ahead of print Feb. 19, 2017.
   2. Zhong Y et al. Blueberry improves the therapeutic effect of etanercept on patients with juvenile idiopathic arthritis: Phase III study. Tohoku J Exp Med;237:183-91, 2015.
   3. Hu Y et al. Sugar-sweetened soda consumption and risk of developing rheumatoid arthritis in women. Am J Clin Nutr; 100:959-67, 2014.
   4. Micha R et al. Association between dietary factors and mortality from heart disease, stroke and type 2 diabetes in the United States. JAMA 317:912-24, 2017.

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In the news: Food & Mood Findings; New Research on Glucosamine, Chondroitin

Diet ‘Tune Up’ May Help Fight Depression

Extensive evidence from observational studies suggests that the quality of our diet could be a protective factor in fending off depression. Diets higher in plant foods (veggies, fruits, beans, nuts and whole grains) and lean proteins (i.e. fish) are linked to a lower risk for depression. Diets with more fast, processed and sugary foods increase the risk for depression.

Those findings led University of Melbourne researchers to conduct a randomized controlled trial, the “SMILES” trial (1), to test whether a modified Mediterranean diet could make a difference for those with major depression and already being treated with antidepressant drugs and/or psychotherapy. For 12 weeks, 67 participants received either social support (known to be helpful in depression) or nutritional support to improve the quality of their diet.

At the trial’s end, the dietary group had a greater reduction in depressive symptoms than the social support group. The dietary group also had a better rate of remission: 33% vs. 8% for the social support group.

This is the first controlled trial to ask: If I improve my diet, will my mental health improve? Larger trials are needed, but the findings are promising.

Glucosamine/Chondroitin: Cancer Risk Link?

Recent evidence from population health studies links the use of glucosamine and chondroitin supplements with reduced risk of both colorectal and lung cancers.

In the newest study (2), a research team from Harvard, the National Cancer Institute, and the Memorial Sloan Kettering Cancer Center explored the association between use of these supplements and the risk of colorectal cancer. The research was done over a 10-year period in participants of two large prospective studies: the Nurses' Health Study and the Health Professionals Follow-up Study.

The use of glucosamine and chondroitin was associated with a 25% reduction in risk of colorectal cancer. The lower risk was similar in both groups of participants after accounting for risk factors such

Similar findings were observed for participants in another trial (the VITAL trial) who used glucosamine and chondroitin 4 or more days a week, though the supplement takers were more likely to exercise regularly, and to eat less red meat and more veggies – factors also linked to lower risk.

In an earlier 2011 study (3), researchers at the Fred Hutchinson Cancer Research Center looking at participants in the VITAL trial, observed that use of glucosamine (though not chondroitin) at least 4 times weekly for 10 years was associated with a 23% reduction in the risk of lung cancer overall and a 51% risk reduction for adenocarcinoma of the lung – the most common type of lung cancer in the US. This association remained the same when aspirin use and smoking were taken into account.

These nutrients may well influence inflammation, as they have been shown to reduce markers of inflammation in healthy, overweight people (4). Inflammation plays an important role in lung carcinogenesis, and is also involved in colorectal cancer development. It’s also very important to point out that the studies to date are observational only, and that these observations must be validated in intervention trials.

So, for now, glucosamine alone or combined with chondroitin may provide useful support for our joints. When it comes to joint health, it’s worth noting that the supporting evidence for glucosamine alone is stronger than that for chondroitin alone.

References

1. Jacka F, et al. A randomised controlled trial of dietary improvement for adults with major depression (the ‘SMILES’ trial). BMC 15: 23, 2017.
2. Kantor ED, et al. Use of glucosamine and chondroitin supplements in relation to risk of colorectal cancer: Results from the Nurses' Health Study and Health Professionals follow-up study. Int J Cancer. 139:1949-57, 2016.
3. Brasky TM, et al. Use of glucosamine and chondroitin and lung cancer risk in the VITamins And Lifestyle (VITAL) cohort. Cancer Causes Control. 22:1333-42, 2011.
4. Navarro SL, et al. Randomized trial of glucosamine and chondroitin supplementation on inflammation and oxidative stress biomarkers and plasma proteomics profiles in healthy humans. PLoS One. 10(2), 2015.

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In the news: Omega-3s in Pregnancy May Help Kids Breathe Easier; Nutrition & Asthma Tips

Omega-3s in Pregnancy Lower Childhood Asthma

Asthma has been steadily increasing over the past few decades, with nearly 9% of US children suffering from the condition. Researchers have long suspected a connection between these rising rates and the low intake of anti-inflammatory omega-3 fatty acids in many Western countries typically eating a “meat-sweet” diet. The results of a study published in the New England Journal of Medicine (1) seem to confirm that idea.

In the trial, Danish researchers randomly assigned 736 women who were 6 months pregnant to receive either 2.4 grams of fish oil (55% EPA and 37% DHA in triglyceride form) or placebo. Blood levels of EPA and DHA were measured in the expectant moms at 24 weeks and 1 week after delivery.

The children were followed for 5 years. For the first 3 years, neither the investigators nor the parents knew who received fish oil. For the 2 years after that, the investigators were still blinded to treatment assignments. Most children who have asthma develop their first symptoms earlier than age 5, but an actual diagnosis is usually only clinically established at 5 years of age.

The research team found a 31% lower risk of persistent wheezing or asthma in the offspring of women who received the fish oil supplement. The risk of lower respiratory tract infections was also reduced in these children.

The effect of maternal omega-3 supplementation was strongest in children whose moms had the lowest blood levels of EPA and DHA at the study’s start or had a gene variant that reduced their ability to produce EPA and DHA from a precursor omega-3 fatty acid. For these children, the risk of developing asthma was reduced by 54%.

One of the researchers noted that women with low blood levels of EPA and DHA are even more common in the US than in Denmark where the study was conducted. Pregnant women are cautioned to avoid over consuming fish – particularly large, predatory fish – which can contain high levels of mercury that can be harmful to the developing fetus. Though the level of omega-3s tested in this study was safely used, future studies should examine whether lower doses in expectant moms might be just as effective (2).

Nutrition Tips for Those with Asthma

Evidence suggests that diet and nutrition may also help those who already have asthma in controlling their symptoms and managing the disease.

Being overweight, for example, can worsen asthma while reducing weight can improve symptoms, which results in less use of asthma medications as well as an improved asthma-related quality of life (3).

Sulfites, used as preservatives in wine and foods such as dried fruits, can trigger asthma symptoms in some people with moderate to severe asthma, so avoiding sulfite-containing foods and beverages might help.

Paying particular attention to several nutrients may also pay dividends:

• Vitamin D – Low levels have been seen in those with more severe disease, and restoring those level may improve asthma (Dec, 2014 and Oct, 2016 Staying Healthy).

• Vitamins C and E – Oxidative stress (an over-production of cell-damaging free radicals) – fosters inflammation leading to lung swelling and irritation. Getting sufficient amounts of these two antioxidant vitamins is important, so a fruit and vegetable-rich diet is the way to go. Some research also supports the use of extra vitamin C, especially in reducing the symptoms of exercise-induced asthma or respiratory symptoms caused by exercise (4).

References

1. Bisgaard, H, et al. Fish oil–derived fatty acids in pregnancy and wheeze and asthma in offspring. NEJM 375:2530-39, Dec. 29, 2016.
2. Ramsden CE. Editorial: Breathing easier with fish oil -A new approach to preventing asthma? NEJM 375:2596-98, 2016.
3. Asthma and obesity: is weight reduction the key to achieve asthma control? Curr Opin Pulm Med. 22:69-73, 2016.
4. Hemilia H. The effect of vitamin C on bronchoconstriction and respiratory symptoms caused by exercise: a review and statistical analysis. Allergy Asthma Clin Immunol.10:58, 2014.

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In the news: Tune into the ‘Med Diet’ for Better Health in the New Year

Med Diet Associated with Lower AMD Risk

Over the past decade, many studies have shown that following a Mediterranean (Med) style diet can have powerful heart health benefits. It’s a diet rich in fresh fruits and veggies, seafood, whole-grains and monounsaturated fats (the type in olive oil), and relatively low in meats, sweets and dairy.

According to growing evidence – the newest published in November, 2016 in the journal Ophthalmology – adopting the Med style of eating may also be protective against age-related macular degeneration (AMD), a leading cause of vision loss in those of us aged 50 and older.

In the latest study (1), researchers used a Med diet score to assess adherence to the diet and prevalence of AMD in over 4,750 participants 65 and older from 7 study centers across Northern and Southern Europe.

Compared to those with the lowest Med diet scores, people who were best at sticking with the diet had a 47% reduced risk of advanced AMD.

Below is the Mediterranean Diet Pyramid (from the Aug. 2008 Staying Healthy entitled Mediterranean Diet Gains Momentum), which canserve as a model to help get started. Here’s to good visual health in the New Year!

Handful of Nuts Daily Lowers CVD & Chronic Disease Risk

Several of the intervention studies that have evaluated the effect of the Med diet on cardiovascular disease (CVD) risk, have shown that adding some nuts daily to the diet confers protection against developing CVD. Nuts contain many bioactive compounds and are high in magnesium, fiber and polyunsaturated fats. Walnuts and pecans in particular are good sources of antioxidant nutrients.

A new analysis of 20 studies (2) that examined nut consumption and risk of CVD as well as other chronic diseases was conducted by university researchers from the UK and Norway. The studies included in the analysis involved over 800,000 participants and included many thousands of cases of heart disease, stroke, CVD and cancer.

The analysis found a consistent reduction in risk across many different diseases with nut consumption. One serving (28 grams or 1 oz.) per day increase in nut intake was associated with a reduction in risk of 29% for coronary heart disease, 21% for CVD, 15% for total cancer, and 22% reduction in risk of all-cause mortality. The results were similar for tree nuts (such as walnuts) and peanuts.

The take home message is clear: add a handful of nuts daily to the heart- and possibly eye-healthy Mediterranean style of eating.

References

1. Hogg RE, et al. Mediterranean diet score and its association with age-related macular degeneration: The European Eye Study. Ophthalmology. [Epub ahead of print] Nov 5, 2016.
2. Aune D, et al. Nut consumption and risk of cardiovascular disease, total cancer, all-cause and cause-specific mortality: A systematic review and dose-response meta-analysis of prospective studies. BMC Medicine. 14:207, 2016.

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In the news: Meal Timing & Potential Weight Loss; Lutein, Lycopene & Skin Health

Meal Timing Gains Research Attention: Potential Weight Control Benefits?

According to the National Institutes of Health, more than two in three adults are considered to be overweight or obese. So it’s no surprise that developing weight loss strategies is a US research priority. One potential strategy was revealed last month by University of Alabama investigators at Obesity Week 2016, the largest international scientific conference on obesity and weight loss.

The timing of eating during the day has been shown to influence metabolism in animal models by reducing fat and lowering the animals’ risk of chronic diseases. The newly presented research (1) is the first to test this proposition in humans.

Called “early time restricted eating”, the idea is to eat a very early dinner or even skip dinner, keeping food intake within a shorter daily timeframe to better align with metabolic activities that function more optimally in the morning.

In the study, overweight or obese participants ate meals between 8 a.m. and 2 p.m. for four days, and then consumed the same number of calories for another four days, this time over the more traditional 8 a.m. through 8 p.m. time period. The amount of calories and fat burned and any impact on appetite was evaluated during the different eating schedules.

The ‘early time’ eating improved oxidation (burning) of fat for several hours at night and it also reduced daily ups and downs in hunger levels. It improved the ability to move between burning carbs and fat, which can be altered in people with insulin resistance – a condition that often accompanies being overweight.

Whether these preliminary findings will translate to a viable strategy for controlling weight is going to require larger studies for longer periods of time. The rationale for restricted early eating makes good scientific sense, but now we need to learn whether it can really help with weight loss and whether people can adapt to a change in meal times.
 
Healthy Skin from Within: Lutein & Lycopene

Everyone gets expression lines, thin wrinkles, and sagging skin as they grow older, which is partly determined by genetics. However, a chief reason for aging skin is "photo-aging" due to sun exposure.

Studies in animals and humans indicate that dietary carotenoids like lutein and beta carotene as well as the antioxidant vitamins C and E accumulate in the skin and play a role in the normal photo-protection of skin. A new study suggests that lycopene (abundant in tomatoes and tomato products) may also play a role.

In this crossover study (2), 65 volunteers were divided into 4 treatment groups. One group took 20 mg of lutein or placebo for 12 weeks then switched to the other treatment after a washout period. The second group was given 20 mg of lycopene or placebo for the same duration in the same fashion.

The placebo and active interventions were separated by a 2-week washout period. Skin was exposed to UV radiation. Both lycopene and lutein blocked the expression of genes that are indicators of oxidative stress and photo-aging.

Two important things to note: Consuming these carotenoids and antioxidants doesn’t mean that we don’t also need topical sunscreen protection as well – we do. Secondly, the high lutein level tested in this study does not appear necessary to offer normal skin protective activity. An earlier study (3) found that lower dose lutein (3 mg daily plus antioxidants) was just as effective as higher dose lycopene plus beta carotene (15 mg total, plus antioxidants) in hydrating skin and lowering oxidative stress in blood – a surrogate measure off UV effects on the skin.

References

1. Peterson C, et al. Time-restricted feeding increases fat oxidation and reduces swings in appetite levels in humans. Abstract T-OR-2081. Presented at: ObesityWeek 2016, Oct 31-Nov 4, 2016; New Orleans, LA.
2. Grether-Beck S, et al. Molecular evidence that oral supplementation with lycopene or lutein protects human skin against ultraviolet radiation: Resutls from a double-blinded, placebo-controlled, crossover study. Br J of Dermatol Epub ahead of print Sept 3, 2016.
3. Morganti P, et al. Protective effects of oral antioxidants on skin and eye function. SkinMed 3:310-16, 2004.

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In the news: Omega-3 + GLA May Support Kids’ Reading Ability; Folic Acid & Stroke Risk

Fatty Acids May Help Improve Reading Skills

The role of polyunsaturated fatty acids such as omega 3s for learning and behavior in children is a growing area of research. Omega 3 fatty acids are essential brain components, and some evidence suggests that they may influence neurotransmitters in the brain.

Several trials have detected positive effects of combined supplemental omega-3 and GLA fatty acids in children with attention difficulties (mostly attention-deficit / hyperactivity disorder, ADHD), or with low reading performance.

Recently, a team of neuroscientists from the University of Goteborg in Sweden examined whether this combination of fatty acids might improve reading ability in mainstream schoolchildren as well.

In the study (1), children aged 9-10 years were randomly assigned to receive omega fatty acid capsules twice daily (total daily dose of 558 mg EPA, 174 mg DHA, and 60 mg GLA) or identical placebo for 3 months.

This was followed by an additional 3-month period when all participants took the fatty acid supplement. The children were evaluated for their reading abilities by a battery of tests (Logos).

Children who received fatty acids during the double-blind phase of the study showed significantly greater improvement than placebo takers on the Logos tests ‘phonologic decoding time’ and ‘visual analysis time’. In other words, these children were faster at decoding words and faster at visual perception – both considered to be essential functions in reading ability.

During the three to six month study period, reading comprehension also improved in the fatty acid group vs. those taking placebo during the first phase.

Among children taking the fatty acids, those who had attention problems, in particular, showed improvements (those with higher ADHD symptoms, but not nearly high enough to be diagnosed with the disorder).
The authors call for further study in both mainstream schoolchildren and those with neurodevelopmental problems to confirm their promising findings.

Folic Acid Lowers the Risk for Stroke

About 795,000 Americans have strokes each year, so reducing the risk for this debilitating condition is a public health priority. Many studies have investigated whether lowering blood levels of the artery-damaging compound homocysteine with supplemental folic acid can help prevent cardiovascular disease (CVD) and ischemic stroke, the most common type of stroke. However, the results of these studies haven’t been consistent.

To learn more, Harvard researchers evaluated 30 randomized trials involving over 82,000 participants to see whether folic acid supplementation is effective in lowering CVD risk (2).

The good news is that folic acid significantly lowered the chances of stroke by 10%. That may seem like a small reduction, but every little bit helps when it comes to stroke prevention. From a public health point of view, a 10% reduction is still very impressive. People who had lower folic acid levels to begin with reaped the most benefit from supplementation. For CVD overall, the risk was slightly lower with folic acid, and improvements were better for those who had no pre-existing CVD or greater reductions in homocysteine.

However for stroke risk, there did not seem to be any difference between the smallest and the largest reductions in homocysteine levels – reducing levels a little or a lot led to similar results. So it’s very possible that homocysteine isn’t the main culprit here, and that folic acid may be protecting against stroke in some other way than simply lowering homocysteine.

References

1. Johnson M, et al. Omega 3/6 fatty acids for reading in children: a randomized, double-blind, placebo-controlled trial in 9-year-old mainstream schoolchildren in Sweden. J Child Psychol Psych. Epub ahead of print Aug 22, 2016.
2. Li Y, et al. Folic acid supplementation and the risk of cardiovascular diseases: A meta-analysis of randomized controlled trials. J Am Heart Assoc. Epub ahead of print Aug 15, 2016.

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In the news: Omega-3 May Benefit Statin Users; Vitamin D Cuts Risk of Asthma Attacks

FH: A Genetic Form of High Blood Cholesterol

Familial hypercholesterolemia (called FH) is a genetic condition in which the body is unable to efficiently remove LDL cholesterol from the bloodstream. This inherited form of high cholesterol results in greatly elevated LDL levels, as well as a higher risk of atherosclerosis and heart attack at an early age.

Those who inherit two copies of the defective FH gene (one from each parent) can develop cardiovascular disease during childhood. The more common form of FH, where only one copy of the abnormal gene is inherited from a parent, can lead to premature cardiovascular disease – often at 30-40 years of age.

The more common form of FH is usually treated with statins or other lipid lowering drugs that reduce blood cholesterol levels. Though statin therapy can help lower the risk of atherosclerosis, some cardiovascular risks still remain.

One of those risks is a reduction in the elasticity of arteries – a risk that is considered a predictor of future coronary heart disease. It’s important for vessels to be supple and elastic so that they can expand and contract continuously as blood pulses through them.

Omega-3s May Add Heart Benefits for Statin Users with FH

To evaluate whether omega-3 fatty acids might improve artery stiffness and other risk factors, Australian researchers conducted a trial in 20 FH patients who were already taking statins (1).

The participants were randomly assigned to receive 4 grams of omega-3 fatty acids daily (1,840 mg EPA and 1,520 mg DHA) or no supplements for 8 weeks. After another 8 weeks of ‘washout’, the patients switched to the other group for an additional 8-week period.

Omega-3 supplementation showed a significant, 9% improvement in elasticity for large (though not small) arteries. Blood pressure was also reduced (6% reduction in both diastolic and systolic pressures) in the Omega-3 group. Additionally, triglycerides dropped 20% and an 8% reduction was seen in levels of Apolipoprotein B – a protein component of LDL cholesterol that transports cholesterol to tissues.

The authors conclude that supplemental omega-3s improved artery stiffness, blood pressure and other risk factors in these FH patients, independent of statin therapy. They believe that the improvements seen in blood vessel elasticity are likely due to a direct effect of the omega-3s on the artery wall.

Vitamin D Cuts Risk of Severe Asthma Attacks

Low blood levels of vitamin D have been linked to an increased risk of asthma attacks in children and adults with asthma. Several clinical trials have evaluated whether vitamin D might prevent asthma attacks and improve control of asthma symptoms.

Now, a major review by the Cochrane group has analyzed the high quality trials that have been conducted, and concluded that vitamin D (taken with standard asthma drugs) can reduce the risk of severe asthma attacks (2). Cochrane reviews are considered to be the highest standard in evidence-based information for health care providers.
 
The analysis, which included 7 trials involving nearly 1,100 children and adults with mild to moderate asthma, found that the risk of having severe attacks was cut in half (from 6% to 3%) with vitamin D supplementation. The rate of attacks requiring steroid treatment was significantly reduced as well.

While the reviewers found a benefit in preventing attacks, they did not find an improvement in everyday symptoms in patients taking asthma medications. It’s still unclear whether the vitamin just helps those who have low vitamin D levels, or all those who suffer severe attacks. The reviewers are working on a second analysis to help answer this question.

References

1. Chan DH, et al. Effect of omega-3 fatty acid supple-mentation on arterial elasticity in patients with familial hypercholesterolemia on statin therapy. Nutrition, Metabolism, and Cardiovascular Disease. Epub ahead of print, Aug. 3, 2016.
2. Martineau AR, et al. Vitamin D for the management of asthma. Cochrane Databse Syst Rev. Epub ahead of print, Sept. 5, 2016.

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In the news: Pre-BBQ Beer Marinade; Metformin Ups Risk of Vitamin B12 Deficiency

Beer for Safer Summertime Grilling

Pulling out the backyard BBQ in summer is an American pastime. But the National Cancer Institute (NCI) has long informed us that meats cooked at high temperatures, especially above 300ºF (as in grilling or pan frying), that are cooked for a long time, or that are exposed to smoke or charring via grilling, tend to form unsafe compounds.

These compounds, called polycyclic aromatic hydrocarbons (PAHs) and heterocyclic amines (HCAs), have been shown to cause cancer in animal models. And population studies link greater intake of well done, fried, or barbecued meats with a higher risk of colorectal, pancreatic and prostate cancers.

The NCI has some tips for reducing the formation of these compounds: avoid direct exposure of meat to an open flame or a hot metal surface, avoid prolonged cooking times, use a microwave oven to cook meat prior to exposure to high temperatures, continuously turn meat over while cooking, and remove any charred portions before eating.

Now, a university research team in Spain offers another suggestion: marinate meat in dark ale before grilling. The researchers marinated samples of pork for 4 hours in Pilsner beer, non-alcoholic Pilsner beer or “Black” beer (dark ale) prior to grilling the meat on a charcoal grill to well done. The dark ale was the most effective, decreasing the level of PAHs by more than half compared to the level in grilled, non-marinated pork (1).

They later conducted the same experiment, this time looking at the effect of the beer marinades on HCA formation (2) in charcoal-grilled pork. All the beer marinades reduced total HCA levels. But, again, the dark ale was most efficient with a level of 90% inhibition. So for safer grilling, look to the NCI tips and have dark ale on hand for pre-grill marinades.

Higher Risk of B12 Deficiency with Metformin

Metformin is usually the first drug prescribed for those with type 2 diabetes to improve blood sugar control. The use of metformin has long been associated with low blood levels of vitamin B12, and this interaction has been evaluated again in the longest and largest study to date (3).

The study was a secondary analysis of the Diabetes Prevention Program/Diabetes Prevention Program Outcomes Study (DPP/DPPOS). Over 2100 participants from DPP/DPPOS received either metformin or placebo for 3.2 years. The metformin group then continued taking the medication for an additional 9 years.

The longer a participant took metformin, the greater their risk of developing B12 deficiency, with the risk rising 13% yearly. Low and borderline-low levels of B12 combined were more common in metformin users than placebo: about 19% vs. 9.5% after 5 years. More neuropathy – damage of peripheral nerves that can result from B12 deficiency or diabetes – was also seen with long-term metformin use.

How metformin and vitamin B12 interact is not fully understood. But according to some studies, 10-30% of people taking this drug show evidence of decreased B12 absorption. Since people over the age of 50 are generally less efficient at absorbing B12 anyway, this drug-nutrient interaction could exacerbate levels that are already low or marginal.

If you are taking this medication for type 2 diabetes, be sure your physician is monitoring your serum B12 levels. B12 injections and/or supplemental B12 may be used to prevent marginal levels or to treat overt deficiencies of this important vitamin.

References

1. Viegas O, et al. Effect of beer marinades on formation of polycyclic aromatic hydrocarbons in charcoal-grilled pork. J Agric Food Chem. 62:2638-43, 2014.
2. Viegas O, et al. Influence of beer marinades on the reduction of carcinogenic heterocyclic aromatic amines in charcoal-grilled pork meat. Food Addit Contam Part A Chem Anal Control Expo Risk Assess. 32:315-23, 2015.
3. Aroda VR, et al. Long-term metformin use and vitamin B12 deficiency in the Diabetes Prevention Program Outcomes Study. J Clin Endocrinol Metab. Epub Feb. 22, 2016.

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In the news: Curcumin Helps Fight Fatty Liver; Chocolate Worsens Acne

Non-Alcoholic Fatty Liver: a Global Health Problem

Non-alcoholic fatty liver disease (NAFLD) refers to the accumulation of excess fat, mainly triglycerides, in the liver cells of people who drink little or no alcohol. This “fatty liver” condition is part of the metabolic syndrome that’s characterized by obesity, diabetes or pre-diabetes (insulin resistance), elevated blood lipids such as cholesterol and triglycerides, and high blood pressure. With the growing rates of obesity and diabetes seen worldwide, it’s no wonder that NAFLD has become a common disorder.
 
Although having fat in the liver isn’t normal, it probably doesn’t damage the liver by itself. But it can lead to more serious problems such as non-alcoholic steatohepatitis or NASH, where the excess fat causes inflammation of liver cells and some degree of tissue scarring.

The first line of defense against NAFLD progressing to NASH is to address the underlying causes of over-weight and insulin resistance through diet and exercise. But researchers have also been looking for complementary means of fighting fatty liver. One recent study investigated the effects of curcumin from turmeric spice in NAFLD, based on promising results from animal studies.

Effects of Curcumin on NAFLD

In this double-blind placebo-controlled trial (1), 80 patients with metabolic syndrome and objective evidence of NAFLD were randomly assigned to receive a supplement (500 mg/day equivalent to 70-mg curcumin) or matched placebo for 8 weeks.
Since curcumin is not well absorbed, the researchers used a formulation that enhanced its absorption.

Compared with placebo, those in the curcumin group had a significant reduction in liver fat content as measured by ultrasound. There were also significant reductions in body mass index, and blood levels of total cholesterol, LDL, triglycerides, liver enzymes and HbA1c (a measure of blood sugar control) compared with the placebo group. These promising results should be confirmed via larger and longer-term trials.
 
Chocolate a No-No for Those with Acne?

The heart health benefits of chocolate and its cocoa polyphenols or flavonoids have received a lot of attention over the past few years. But for younger people with acne, passing on chocolate treats may be a better way to go.

Whether or not chocolate can worsen acne has been controversial. A study published years ago found that it didn’t, and was replaced by the idea that the sugar content in chocolate might be the culprit. However, that original study has been criticized for flaws in its design.

To revisit this controversial topic (2), investigators assigned 54 college students with acne vulgaris to consume a 1.55 oz. milk chocolate bar or 15 jelly beans – a non-chocolate candy with a similarly high glycemic load (a measure of a food’s impact on blood sugar). Participants also completed dietary logs.

The researchers, who were blinded to the sweet assignment, evaluated acne changes 48 hours later with before and after photographs of participants. After a 4 week washout, the participants switched to the opposite test candy and were again assessed.

Compared to eating the jellybeans, consuming the chocolate bar significantly increased the number of acne lesions.

The authors noted that the flavonoids in chocolate most likely accounted for the findings. But they suggest additional studies with more participants, using specific components of chocolate, and with more diligent documentation of the participants’ diets and menstrual cycles.

References

1. Rahmani S, et al. Treatment of Non-alcoholic Fatty Liver Disease with Curcumin: A Randomized Placebo-controlled Trial. Phytother Res. June 8, 2016 [Epub ahead of print].
2. Delost G, et al. The impact of chocolate consumption on acne vulgaris in college students: A randomized crossover study J Am Acad Dematol. 75:220-22, 2016.

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In the news: Gluten-Free Diet Shortfalls; “Multi” Use Linked to Better Heart Health

Gluten-Free? Watch Out for Nutrient Shortfalls

Gluten is a protein found in grains such as wheat, barley, rye and triticale (a cross between wheat and rye). People with celiac disease or allergy to wheat protein have to avoid gluten-containing foods because they trigger an autoimmune or allergic response that inflames and damages the small intestines.

But eliminating gluten from the diet has also become increasingly popular among non-celiac, “gluten-sensitive” individuals who identify digestive, mood, and energy symptoms with consuming this protein.

How do gluten-free diets stack up against non-gluten free diets in terms of balanced nutrition? To evaluate the nutritional quality of these diets, researchers reviewed published studies on that diet over the last 25 years (1). For one thing, they found gluten-free diets to be poor in fiber – no surprise because of the necessary avoidance of fiber-rich grains.

The gluten-free diet also was found to have a higher glycemic load compared with non-gluten free diets. Diets with a higher glycemic load can increase blood sugar levels more rapidly, and may lead to weight gain. Many products free of gluten are made from refined flour and starch. When grain is processed to remove gluten, the outer fiber-containing layer is removed leaving starchy, sugary flour with a higher glycemic index.

Additionally, gluten-free eating patterns were seen to be higher in saturated fats and calories compared to non-gluten free diets.

In terms of vitamins, the most common deficiencies were B12, D, and folic acid. Calcium, magnesium, iron and zinc topped the list for common mineral shortages.

So what strategies can improve the quality of gluten-free diets? Choose and prepare gluten-free grains and limit your intake of processed gluten-free products. Grains that don’t contain gluten include quinoa, buckwheat (kasha), amaranth, rice (brown or white), millet, soy and corn (meal, flour, grits, etc). Read product labels to avoid high saturated fat content, and consider taking a daily multi-nutrient supplement to help close potential vitamin and mineral gaps.

Can Long-Term Multi Use Lower CVD Risk?

That question prompted Harvard researchers to examine whether taking a daily multivitamin/mineral supplement over the long haul is associated with the risk of cardiovascular disease (CVD) in healthy men.

The investigators studied 18,530 male physicians from the Physicians’ Healthy Study I, who were free of CVD at the study’s start (2). The participants provided clinical, lifestyle, and dietary information including their use of dietary supplements, and were followed for just over 12 years on average.

While there was only a relatively weak association between multi use and heart benefits in the shorter term, longer use – for 20 or more years – was associated with a 44% lower risk for major CVD events including heart attack, stroke and death from CVD. Multi use was also linked to a lower risk of ischemic reperfusion injury. This injury happens after a shortage of blood and oxygen to the heart resolves. The high oxygen flowing back in triggers inflammation and more damage.

Since supplement users are generally more health-conscious than non-users, it’s possible that the observed CVD risk reduction simply reflects healthier behavior. However, CVD develops over a long period of time, and various vitamin and minerals have been shown to protect LDL cholesterol from oxidation, promote the arteries’ ability to dilate when needed, and to bolster homocysteine metabolism – mechanisms that may well contribute to CVD prevention over time. The authors also note that several other observational studies have also reported cardiovascular benefits among long-term multi users.

References:

1. Vici G, et al. Gluten free diet and nutrient deficiencies: A review. Clin Nutr. May 7, 2016 [Epub ahead of print].
2. Rautiainen S, et al. Multivitamin use and the risk of cardiovascular disease in men. J Nutr. 46:1235-240, 2016.

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Recent Findings on Omega-3s & Depression

Depression Affects Many Americans

Major depression (also called clinical depression) is a serious mood disorder that causes severe symptoms. Major depression is common according to the National Institute of Mental Health (NIMH). In 2014, roughly 15.7 million U.S. adults aged 18 or older had at least one major depressive episode in the past year.

Medically, a major depressive episode is defined as a period lasting 2 weeks or longer during which there is either depressed mood or loss of interest or pleasure, and at least four other symptoms that reflect a change in functioning, such as problems with sleep, eating, energy, concentration, and self-image.

Depression can also be mild or moderate. The mild form causes symptoms that can affect daily activities, though people continue to function – just not as well as they normally do. These symptoms are worse in moderate depression, and can cause real difficulties at home, work, and in social situations.

Omega-3 Fatty Acids and Depression

The omega-3s have been studied in depression, and the best evidence for their benefit has been seen in major and moderate depression. Several recent trials have shed some light on which of the omega-3s – EPA or DHA – may be more important, whether the omega-3s can make a difference for those already on antidepressant drugs, and how these fatty acids might be working to help stabilize mood.

More EPA or DHA for Depression?

A multinational research team recently performed a meta-analysis of 35 randomized clinical trials to better understand why some trials have found benefit of omega-3s in depression while others haven’t (1). Clinical benefits were seen in depressed patients given supplements containing predominately EPA (more than 50%), while supplements with higher DHA (>50% DHA) did not show benefits. DHA may be important too, but the benefits seem to depend more on the EPA content.

Omega-3s Boost Antidepressant Drug Effects

Antidepressant drugs can fall short for many people: A large-scale NIMH study found that less than 50% of people become symptom-free on antidepressants. Researchers from Harvard and the University of Melbourne recently conducted a review and meta-analysis of 40 clinical trials that looked at the ability of various nutrients to improve the response to anti-depressants when needed (2). While some nutrients like vitamin D and folic acid improved the response to common drugs (including SSRI and tricyclic drugs), the strongest effect was seen with fish oil omega-3s.

How Might Omega-3s Impact the Brain?

Fish oil may enhance white matter in regions of the brain that can be compromised in depression. White matter consists of myelinated fibers that connect brain cells. Myelin, made of protein and fats, covers many nerve fibers to boost the speed at which they conduct impulses.

Since blood levels of the omega-3s can be low in major depression and these fatty acids affect myelination, Columbia University researchers theorized that fish oil might help ease depression by improving the structural integrity of white matter.

To test this theory, patients with severe depression underwent brain imaging before and after 6 weeks of fish oil supplementation (3). Eighty percent of those whose depression improved with fish oil had increased white matter in important brain areas, while an increase was seen in only 45% of those who didn’t respond to the supplement. These findings offer one explanation for how omega-3s help combat depression along with their inflammation-fighting actions.

References:

1. Hallahan B, et al. Efficacy of omega-3 highly unsaturated fatty acids in the treatment of depression. Br J Psychiatry [Epub ahead of print] April 21, 2016.
2. Sarris J, et al. Adunctive nutraceuticals for depression: a systematic review and meta-analyses. Am J Psychiatry [published online April 26, 2016].
3. Chhetry BT, et al. Omega-3 polyunsaturated fatty acid supplementation and white matter changes in major depression. J Psychiatr Res 75:65-74, 2016.

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In the news: Vitamin C & Cataract; Overnight Fast Time in Early Breast Cancer

Influence of Nature vs. Nurture on Cataract

Growing older, smoking, oxidative stress and antioxidant intake are factors that have been associated with nuclear cataract, the most common age-related type of cataract or clouding of the eye’s lens. The genes we inherit are also thought to play a role in susceptibility to cataract formation.

Specific genes have recently been linked to nuclear cataract development in Asian populations, but little is known about genes associated with cataract risk in other populations.

One way to learn more about the influence of nature vs. nurture is to study pairs of twins, who share most of the same DNA. To gain insight into the relative importance of genes and the connection between antioxidants and nuclear cataract progression, UK researchers studied 324 pairs of twins. About 150 of the twins were identical, and the rest were fraternal. The investigators assessed the twins’ lenses and diet and followed them for about 10 years.

Vitamin C-rich Diets May Help Save Sight

At the study’s start (1), eating more vitamin C-containing foods and at least 2 fruit and 2 vegetable servings daily translated to about a 20% lower risk of cataract.

Nine to ten years later, those twins who consumed more dietary vitamin C – at least 150 mg daily – had a 33% lower risk of cataract progression versus those who consumed less. The researchers believe that tears higher in vitamin C bathe the lens and better protect them from oxidative stress.

According to the researchers, genetic factors explained 35% of the difference in progression of nuclear cataract over a 10-year period, while 65% was due to environmental factors like diet.

What about vitamin supplements? In this study, no association was found between the use of dietary supplements and cataract. However, fewer than 10% of participants reported using any individual supplement, so all supplements were grouped together. That makes it difficult to draw conclusions about the effect of any single supplement or of any supplement ingredient (e.g., supplemental vitamin C) on cataract.

Bottom line: A healthy diet overall may help protect our eyesight – one that includes vitamin C-rich foods such as oranges, papayas, cantaloupes, bell peppers, strawberries, kiwis, broccoli and dark green leafy veggies.

Breast Cancer: Does It Matter When We Eat?

Much of the research conducted on diet and breast cancer to date has focused on what to eat to help prevent this cancer, such as specific foods, food groups and overall dietary patterns. But a new theory has emerged that when we eat also matters, with research showing that timing of food intake influences metabolic health and cancer.

A landmark study with mice, for instance, showed that a 16-hour bedtime fasting regimen protects mice on a high-fat diet from abnormal glucose metabolism, inflammation, and weight gain. And in an analysis of over 2,100 diabetes-free women, longer nightly fasting was associated with significant improvements in markers of blood sugar control.

In a new analysis (2) of 2,400 participants in the Women’s Healthy Eating and Living Study, the relationship between eating before bedtime and cancer outcomes were tested. The women had early stage breast cancer, were not diabetic, and were followed for over 11 years.

Those who fasted less than 13 hours each night had a 36% higher risk for breast cancer recurrence vs. women who didn’t eat for 13 hours or more. No link between shorter nighttime fasts and higher risk of death was seen.

Closer examination revealed that each 2-hour increase in nightly fasting was linked to longer nighttime sleep and lower HA1c levels – an important indicator of blood sugar control. While more studies are needed to confirm these results, prolonging nighttime fasting may be a simple strategy for helping to prevent breast cancer from returning, according to the authors.

References

1. Yonova-Doing E., et al. Genetic and dietary factors influencing the progression of nuclear cataract. Ophthalmol [ePub ahead of print Mar 15, 2016].
2. Marinac C.R., et al. Prolonged nightly fasting and breast cancer prognosis. JAMA Oncology [ePub March 31,2016].

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In the news: Magnesium & Arteries; Omega-3s & Breast Cancer Risk, Blood Pressure

Magnesium Linked to Healthier Arteries

Magnesium plays many roles in the body from helping to maintain healthy blood pressure, muscle and nerve function, to keeping heart rhythm steady and bones strong. A newly published study suggests that higher magnesium levels may reduce the risk of hypertension and calcification of the coronary arteries (1).

Researchers from Mexico’s National Institute of Cardiology conducted a population health study, measuring serum magnesium levels in more than 1,200 men and women aged 30-75 and free of symptomatic cardiovascular disease (CVD). An imaging procedure called computerized tomography was used to assess artery calcification.

After adjusting for other factors, the investigators found that low serum magnesium was independently associated with a higher prevalence not only of hypertension and type-2 diabetes, but also of coronary artery calcification – a predictor of CVD.

Participants with the highest average magnesium blood levels had a 48% lower risk of hypertension, 69% lower odds of having type-2 diabetes, and 42% lower odds of coronary artery calcification, compared to those with the lowest serum magnesium. Poor intake or low blood levels of this mineral have been linked to a higher risk of calcium in arteries in Korean and US population studies as well.

The 2015 Dietary Guidelines Advisory Committee has tagged magnesium as a nutrient commonly under-consumed. Good dietary sources include fruits, green leafy vegetables, whole grains, nuts and dairy.

Omega-3 May Lower Breast Cancer Risk

Being overweight or obese is a major breast cancer risk factor for post-menopausal women. Experts believe that inflammation is an important underlying cause, and normal weight women have less inflammation than heavier women.

Since omega-3 fatty acids have anti-inflammatory actions, researchers from Penn State, Emory and Colorado State Universities teamed up to examine the impact of omega-3s on breast density in women of different weights (2). Breast density is a validated biomarker for breast cancer risk – the higher the density the more likely cancer will develop. (High breast density means there’s more breast and connective tissue compared to fat in the breast).

Over 260 healthy post-menopausal women with high breast density received either the anti-estrogen drug Raloxifene, omega-3 (EPA and DHA), omega-3 and the drug combined or no treatment during this 2-year long study. Half the participants were normal weight, 30% overweight, and 20% were obese.

Increasing blood levels of omega-3 (DHA only) were associated with decreased breast density, and only in those bordering on obesity or obese. These promising results need to be confirmed in larger trials, perhaps testing EPA/DHA and DHA alone.

Lower Doses of Omega-3s for Hypertension?

Even modest amounts of omega-3s may lower blood pressure in clinically meaningful amounts for those with systolic hypertension, according to results of a study from the UK (3). The majority of trials looking at these fats and hypertension have used 3,000 mg of omega-3s or more, but recent studies have explored lower amounts in the 500 mg to 1,000 mg range.

In this analysis of a randomized controlled trial of over 300 participants, either 700 mg or 1,800 mg of supplemental omega-3 was given for 8 weeks. The results showed that both doses reduced systolic pressure by about 5 mmHg, but only in those with elevated systolic blood pressure at the trial’s start.

This level of blood pressure reduction would translate to about a 20% decrease in CVD risk in middle age, according to the authors, and is an amount achievable by consuming 2-3 weekly portions of oily fish.

References

1. Posadas-Sanchez R, et al. Serum magnesium is inversely associated with coronary artery calcification in the Genetics of Atherosclerotic Disease (GEA) study. Nutr J, 15:22, 2016.
2. Sandhu N, et al. Influence of obesity on breast density reduction by omega-3 fatty acids: Evidence from a randomized clinical trial. Cancer Prev Res, Dec 29, 2015 [Epub ahead of print].
3. Minihane AM, et al. Consumption of fish oil providing amounts of EPA and DHA that can be obtained from the diet reduces blood pressure in adults with systolic hypertension: A retrospective analysis. J Nutr, 146:516-23, 2016.

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In the news: Potential Pitfalls of Too Little Zinc, Vitamin D & Vitamin E

Zinc Boosts Immune Function in Older People

The ability of our immune system to respond efficiently often declines as we grow older. A number of nutrients play a role in supporting healthy immune function, and zinc is among them.

Marginal intakes of zinc among adults 60 or older are fairly common according to survey data. Inadequate zinc levels are thought to be a risk factor for respiratory illnesses including pneumonia in the elderly (1). In fact, an analysis of the AREDS trial found lower mortality in participants who received zinc – either alone or with antioxidants, possibly due to a protective effect against respiratory causes of death.

A new study from Tufts and Harvard Medical School underscores the need to get enough of this important mineral with advancing age (2).

The researchers gave elderly people with low blood levels of zinc, either a supplement of 30 mg zinc daily or a placebo. After 3 months, blood zinc levels had increased, though they were still not adequate in some participants who had very low levels initially. The improvement in zinc levels was associated with enhanced T-cell function, mainly from more T-cells being produced.

Different cells of the immune system contribute to the impaired immunity that can occur with age, but T cells have been shown to be the major contributor. T-cells attack and destroy cells inflected with a foreign invader such as a virus.

Suboptimal Vitamin E Levels Common

If zinc intake can be a problem for older adults, low intakes of vitamin E appear to be widespread among younger and middle-aged adults.

Using the most recent biomarker data available from the National Health and Nutrition Examination Survey, researchers found that only 1% of participants were clinically deficient in vitamin E (serum alpha-tocopherol concentration under 12 μmol/L) (3). Despite the lack of clear-cut deficiency, however, a large portion of people had inadequate blood levels of vitamin E (serum alpha-tocopherol concentration less than 30 μmol/L):

•  87% of persons 20-30 years of age
•  68% of those 31-50
•  43% of those 51 and older

The findings aren’t that surprising since the 2015 US Dietary Guidelines Advisory Committee identified vitamin E as a ‘shortfall nutrient’ with greater than 90% of American adults not getting recommended amounts.

What do these findings mean for health? Since vitamin E plays a vital role in supporting healthy pregnancy and development, the authors find the suboptimal levels among those of reproductive age to be concerning. Low vitamin E has also been associated with age-related changes in brain function, and vitamin E may help maintain liver function as well.

Vitamin D Linked to Dry Eye Risk

New findings of a small study conducted at a research hospital in Turkey add to the body of evidence linking low vitamin D blood levels to dry eye (4).

Researchers evaluated 50 premenopausal women with vitamin D deficiency comparing them with 48 women with adequate vitamin D levels. Both objective tests of dry eye (Schirmer’s and tear break-up time) and subjective measures (OSDI) showed dry eye to be more common in those with vitamin D deficiency.

vitamin D may help protect against dry eye by enhancing tear film stability and reducing ocular surface inflammation, according to the study’s authors.

References:

1. Barnett JB. Zinc: a new risk factor for pneumonia in the elderly? Nutr Rev 68: 30–37, 2010.
2. Barnet JB, et al. Effect of zinc supplementation on serum zinc concentration and T-cell proliferation in nursing home elderly: a randomized, double blind, placebo-controlled trial. Am J Clin Nutr [EPub ahead of print Jan 27, 2016].
3. McBurney MI, et al. Suboptimal serum α-tocopherol concentrations observed among younger adults and those depending exclusively upon food sources, NHANES 2003-2006. PLoS One Volume 10, Number 8:e0135510.
4. Yildrim P, et al. Dry eye in vitamin D deficiency: More than an incidental association. Int J Rheum Dis 19:49-54, 2016.

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In the news: Think Positively about Aging; Higher Omega-3s Linked to Better Cognition in Teens

Alzheimer’s & Negative Stereotypes of Aging

Yale researchers report finding a preliminary link between Alzheimer’s and what they call negative age stereotypes (1) – holding negative beliefs about aging, such as old people are “decrepit” and “absent-minded”.

Although negative age stereotypes have been found to predict a number of adverse outcomes among older individuals, the researchers wanted to explore whether the influence of these stereotypes might also affect brain structure and biomarkers of Alzheimer’s.

To do this, they drew upon participants in the Baltimore Longitudinal Study of Aging who were free of dementia at the study’s start. Age stereotypes were assessed, and up to 10 yearly MRI brain scans were performed.

Those who held more negative age stereotypes earlier in life were found to have significantly steeper shrinkage of the hippocampus, a critical brain region for maintaining memory.

They had also accumulated more neurofibrillary tangles (twisted strands of protein that build up inside brain cells), and amyloid plaques (protein clusters that build up between brain cells) – changes typically seen in the brains of people who have died with Alzheimer’s.

The researchers think that cumulative stress generated by the negative beliefs about aging may help trigger these brain changes. While more human research is needed to verify these findings, a series of studies have found that experimentally stressed animals show similar changes. The authors also point out that the rate of Alzheimer’s in the US, where negative age stereotypes are common, is 5 times that of India where elders are traditionally venerated.

There are ways to help combat negative stereotypes and adopt a more positive outlook, which is key to managing stress. For tips on positive thinking, try the Mayo Clinic website.

Omega-3s & Faster Information Processing

Teenagers with higher blood levels of omega-3 fatty acids may have better information processing speeds, according to a university study conducted in The Netherlands (2). Speed of information refers to how quickly students can react to incoming information, understand it, and formulate then execute a response.

The researchers used baseline data from 266 students, aged 13-15, who participated in a randomized, double blind trial. Blood samples were used to calculate the Omega-3 Index, and a battery of tests was used to assess cognitive performance. The amount of EPA + DHA stored in red blood cells relative to other fatty acids is called the Omega-3 Index. The American Heart Association considers a poor index score a risk factor for heart disease, while an index of 6.5% or more correlates with lower risk of cardiovascular disease (CVD). Some experts recommend a range of 8-11%.

In this study, having a higher Omega-3 index was associated with better information processing speeds and attention. The average Omega-3 index in this group of Dutch students was 3.83%, which is relatively low. Nearly 14% of the participants said they didn’t consume fish, and 77% ate fish only rarely.

Americans fare no better. A recent paper (3) reports that some 95% of a nationally representative US sample had an Omega-3 index less than 4%. In addition, the newly published Dietary Guidelines (2015-2020) emphasize that eating at least 8 oz. of seafood weekly (250 mg of EPA and DHA) is associated with lower cardiac deaths among people with and without preexisting CVD, as well as healthier infants among pregnant and breastfeeding women.

References

1. Levy A, et al. Culture–brain link: Negative age stereotypes predict Alzheimer’s disease biomarkers. Psychology and Aging, Epub ahead of print Dec 7, 2015.
2. van der Wurff ISM, et al. Association between blood omega-3 index and cognition in typically developing Dutch adolescents. Nutrients, 2;8(1):E13, Jan, 2016.
3. Murphy RA, et al. Suboptimal Plasma Long Chain n-3 Concentrations are Common among Adults in the United States, NHANES 2003–2004. Nutrients, 7:10282-89, 2015.

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In the news: Oxidative Stress in Metabolic Syndrome: Obese May Need More Vitamin E

Obesity, Inactivity & Metabolic Syndrome

Metabolic syndrome, which is closely tied to rates of obesity and inactivity, is becoming more common among Americans. As a forerunner of type 2 diabetes and early heart disease, the “syndrome” is estimated to affect 1 out of 3 adults. Hallmarks of metabolic syndrome are a thick waistline and insulin resistance – the body’s ineffective use of insulin, so that sugar builds up in the blood instead of getting into cells.

Overeating & Insulin Resistance

How overeating promotes insulin resistance isn’t fully understood, but experiments in lab animals reveal that overeating can lead to insulin resistance very rapidly, long before the animals gain much weight.

A number of mechanisms could explain this finding: high blood levels of fatty acids, inflammation, stress in the cell’s manufacturing and packaging system (endoplasmic reticulum), or oxidative stress which occurs when too many free radicals are produced for antioxidants to quell them. All of these factors have been seen in obese people who are insulin resistant. But, according to the authors of a new study, no one really knows how the whole process gets started (1,2).

The 6,000 Calorie/Day, 7-Day Experiment

To shed more light on what initiates insulin resistance with overeating and weight gain, investigators recruited 6 healthy, middle-aged men who spent one week of inactivity in a hospital setting, eating 6,000 calories daily of typical American food – about 2 ½ times their normal intake. (It would be like all day lounging and eating Double Whopper burgers with cheese, milk shakes and larges fries for each meal).

The men were weighed and had blood samples taken daily. Fat tissue was also biopsied at the beginning and close of the 7-day food extravaganza. At the end of the week, the men had gained an average 7.7 lbs. (all fat!) and experienced an average 50% decline in their insulin-stimulated glucose uptake into tissues.

No increase in fatty acid levels and no inflammatory or endoplasmic reticulum stress were seen. But after just 2-3 days, both oxidative stress and insulin resistance were present, suggesting that the initial event caused by overeating may be oxidative stress. A close look at the biopsied fat tissue, in fact, showed that oxidative stress caused damage to a key protein that transports glucose into cells (GLUT4).

The exaggerated conditions of this study make it hard to draw absolute conclusions about oxidative stress as the initiating culprit. Yet there’s no doubt that oxidative stress is important, and that many people are inactive and consume too many calories. Bottom line? Move more, eat less, and choose more antioxidant-rich fruits and vegetables.

Obese Need More Vitamin E, Get Less

Results of a new study suggest that obese people absorb less vitamin E when they really need more to help combat the effects of metabolic syndrome (3).

Researchers theorized that vitamin E as a fat-soluble vitamin, would be more available in overweight people who eat large amounts of fatty foods. They tested the theory by giving RDA levels of vitamin E along with non-fat, reduced fat or full-fat milk to healthy people and those with metabolic syndrome.

Contrary to expectations, milk with or without fat promoted absorption of vitamin E in both groups. However those with metabolic syndrome absorbed less of the vitamin than the healthy group. While it wasn’t clear how the ‘syndrome’ blunts absorption, it could impair absorption from the small intestine or decrease its ability to find it’s way to other tissues – like fat – that need vitamin E. The team is now working to determine recommendations for the increased vitamin E needed by those with metabolic syndrome.

References

1. Bodgen G, et al. Excessive caloric intake acutely causes oxidative stress, GLUT4 carbonylation, and insulin resistance in healthy men. Sci Transl Med. 7(304):304re7, Sept, 2015.
2. Akst J. The 6,000-calorie diet. The Scientist, Nov.1, 2015.
3. Mah E, et al. α-Tocopherol bioavailability is lower in adults with metabolic syndrome regardless of dairy fat co-ingestion: a randomized, double-blind, crossover trial. Am J Clin Nutr 102:1070-80, Nov. 2015.

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New Sleep Time Recommendations

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Getting a good night’s sleep helps repair the body and promotes health and well-being. Too little sleep (less than 5-6 hours) may quadruple our susceptibility to catching a cold, for example (1). And both too short a sleep time – as well as sleeping too long – have been linked to an increased risk of stroke (2). So how much sleep time should we aim for?

In February of this year, the National Sleep Foundation (NSF) provided some guidance on this question when it issued new recommendations for appropriate sleep times by age groups (shown on page 2) (3). The NSF sleep time ranges are defined as “recommended”, “not recommended” or, acknowledging that individuals can vary in how much sleep they need, “may be appropriate for some”.

“This is the first time that any professional organization has developed age-specific recommended sleep durations based on a rigorous, systematic review of the world scientific literature relating sleep duration to health, performance and safety,” according to Charles A. Czeisler, PhD, MD, NSF’s chairman of the board and a sleep expert at Harvard Medical School. The NSF convened a panel of experts from multiple disciplines – sleep, anatomy and physiology, as well as pediatrics, neurology, gerontology and gynecology – to reach a consensus on the new recommendations.

Not getting enough sleep – poor quality as well as too few hours – can cause more than foggy thinking, a grumpy disposition, and poor decision-making. Continual lack of adequate sleep can lower the body’s defenses and increase the risk of developing a number of chronic illnesses. According to Harvard’s sleep information website (4), studies have found that getting less than 5 hours of sleep nightly increases the risk of death from all causes by 15%.

Lack of Sleep Can Contribute to Weight Gain

Along with too little physical activity and overeating, sleep is also being considered as a potential risk factor for obesity. Studies have shown, for example, that people who usually sleep less than 6 hours nightly are much more likely to have a higher than average body mass index (BMI), while those sleeping 8 hours per night have the lowest BMI.

According to the Harvard site, the body secretes hormones that help control appetite, energy metabolism, and glucose processing during sleeping hours. Obtaining too little sleep can upset the balance of these and other hormones.

Poor sleep, for example, is associated with increases in insulin secretion and the production of cortisol (the “stress” hormone). It’s also associated with lower levels of the hormone leptin that signals the brain that we’ve eaten enough food, and higher levels of the appetite stimulant ghrelin.

These changes may result in food cravings, and the likelihood of eating more sweets for an energy boost. To top it off, inadequate sleep can leave us too tired to exercise and use up the extra calories consumed.

What We Eat May Influence Sleep

If lack of sleep can affect our eating behaviors, our food choices may also influence sleep. Consuming certain types of foods which impact the availability of the amino acid tryptophan as well as the production of the neurotransmitters serotonin and the “sleep hormone” melatonin may aid in promoting sleep (5).

Promote sleep by choosing complex carbohydrates (whole grain breads and pastas, brown rice), while avoiding sugary foods, which may reduce serotonin levels. Lean proteins like low-fat cheese, chicken and fish are high in tryptophan, which tends to increase serotonin levels. The caveat here is to avoid deep-fried fish and chicken as they can take longer to digest and may keep you awake.

Finally, for a host of tips on how to get a better night’s sleep, visit the National Sleep Foundations website (sleepfoundation.org).

National Sleep Foundation’s Sleep Duration Recommendations*

* Courtesy of the National Sleep Foundation; recommendations for infants and children younger than 3 years are omitted.

References

1. Prather AA, et al. Behaviorally Assessed Sleep and Susceptibility to the Common Cold. Sleep 1;38:1353-9, 2015.
2. Kawachi T, et al. Sleep Duration and the Risk of Mortality from Stroke in Japan: The Takayama Cohort Study. J Epidemiol. Oct 31, 2015. [Epub ahead of print].
3. https://sleepfoundation.org/media-center/press-release/national-sleep-foundation-recommends-new-sleep-times
4. http://healthysleep.med.harvard.edu/healthy/matters/consequences/sleep-and-disease-risk
5. Chaput JP. Sleep patterns, diet quality and energy balance. Physiol Behav. 134:86-91, 2014.
6. Prather AA, et al. Behaviorally Assessed Sleep and Susceptibility to the Common Cold. Sleep 1;38:1353-9, 2015.
7. Kawachi T, et al. Sleep Duration and the Risk of Mortality from Stroke in Japan: The Takayama Cohort Study. J Epidemiol. Oct 31, 2015. [Epub ahead of print].
8. https://sleepfoundation.org/media-center/press-release/national-sleep-foundation-recommends-new-sleep-times
9. http://healthysleep.med.harvard.edu/healthy/matters/consequences/sleep-and-disease-risk
10. Chaput JP. Sleep patterns, diet quality and energy balance. Physiol Behav. 134:86-91, 2014.

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In the news: Vitamin D and Brain Health: More Outdoor Time for Better Vision

Low Vitamin D Linked to Faster Mental Decline

For older individuals, low levels of vitamin D might contribute to a more rapid decline in memory and thinking skills according to research published in the journal JAMA Neurology (1).

A team from Rutgers University and UC Davis analyzed information from a diverse group of older men and women who participated in Alzheimer’s research in Northern California.

The 382 participants in this analysis included people whose cognitive abilities were normal for their age, those with mild cognitive impairment (MCI), and those with dementia. MCI can involve problems with memory and thinking that are noticeably greater than the changes commonly seen with normal aging, but far less than the more serious decline of dementia

At the beginning of the study, more than a quarter of the participants were deficient in vitamin D, and 35% had inadequate blood levels (as measured by plasma 25-hydroxyvitamin D). Levels were lower in people of color (African-Americans and Hispanics) than in white participants.

After about 5 years of follow-up, the rate at which cognitive skills declined was found to be substantially faster – about 2-3 times faster – In those with deficient or low vitamin D levels compared to those whose blood levels were considered adequate.

The accelerated decline was seen in the cognitive processes called executive function and episodic memory, which is the ability to remember past experiences that happened at a particular time and place. Executive function refers to mental skills that help the brain organize and act on information – skills that allow us to organize, prioritize, pay attention, plan and get started on tasks.

This is not the first study to find that vitamin D insufficiency predicts cognitive decline, though whether vitamin D supplements can help slow down cognitive decline needs to be evaluated in future studies. In the meantime, we do know that nearly every tissue and cell type in the body has receptors for vitamin D, including the brain. So maintaining adequate levels of the vitamin makes good sense for overall health.

More Time Outside, Less Myopia: Follow-up

The May issue of Staying Healthy reviewed some of the theories for why the worldwide incidence of myopia, or near-sidedness, in children has increased
so dramatically. (For background, see May issue.

Here in the US, the commonness of myopia in those aged 12-54 grew from 25% in the early 1970’s to about 42% by 2004 according to National Eye Institute data. In some parts of China, 90% of high school graduates have near-sightedness, while myopia rates are lower but increasing in Europe and the Middle East, according to the authors of a new study from China (2).

The researchers assigned children in a dozen primary schools to an extra 40 minutes of outdoor activity or to continue their existing class schedule. Nearly 2,000 six year-old first-graders were included in the study.

After 3 years, about 30% of the outdoor activity group had developed myopia, versus almost 40% of children who continued their usual activity.

The study didn’t attempt to determine why more time outside – even a modest 40 minutes daily – was found to be protective, but the authors do note that bright light may help avert the development of myopia by affecting eye growth – one of the current leading theories for the increase in myopia. Some feel that the jump in myopia rates also may have something to do with too much time spent on near vision tasks like computer use, coupled with an inherited predisposition for the condition.

References

1. Miller JW, et al. Vitamin D status and rates of cognitive decline in a multiethnic cohort of older adults. JAMA Neurol. Sept. 14, 2015. [Epub ahead of print].
2. He M, et al. Effect of time spent outdoors at school on the development of myopia among children in China: A randomized clinical trial. JAMA. 314:1142-8, 2015.

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In the news: Vitamin C Mimics Exercise Benefit: New Studies on Vitamin D & Health

Vitamin C Benefits Cardiovascular Health

Results of a new study conducted at the University of Colorado, Boulder, suggests that daily supplements of vitamin C can have similar benefits for blood vessels as walking in adults who are overweight and obese (1).

It’s the job of a protein called endothelin-1 (ET-1) to constrict small blood vessels when needed. But ET-1 is overactive in the vessels of people who carry excess weight. The higher ET-1 activity makes small vessels less responsive to blood flow demands, promotes inflammation, and increases the risk of developing high blood pressure and vascular disease such as stroke and heart attack.

In the 3-month study, 35 inactive overweight or obese participants with poor vascular tone were divided into two groups: one group of 20 received 500 mg of vitamin C daily with no change in their physical activity, while the other group of 15 took a brisk walk 5-7 times weekly. At the study’s end, the supplemental vitamin C lowered ET-1 related blood vessel constriction as well as the regular walking did.

This study is fairly small and the results need to be confirmed in larger and longer trials. However, the findings might be helpful for those who find it challenging to include exercise in their daily routine. Less than half of obese or overweight patients who are counseled to exercise for better health actually follow through on this advice, according to the researchers.

Keep in mind, though, that a daily brisk walk yields many benefits: it strengthens the heart, helps keep LDL-cholesterol and blood pressure levels in check, tones muscles, boosts energy, and lifts your mood.

New Reviews/Studies on Vitamin D & Health

A number of studies have been recently published on vitamin D that merit attention. Here’s a brief summary:

Vitamin D & Falls – In a pilot study (2), homebound seniors received a high dose vitamin D supplement or placebo monthly for 5 months through the Meals-on-Wheels program. Over half of the seniors had low vitamin D blood levels, and less than a quarter of them had optimal levels at the start of the study. At the conclusion, vitamin D levels had significantly improved in most of the participants in the supplemented group, and the rate of falling in that group was more than cut in half. Other studies have also reported fewer falls in seniors when low vitamin D levels were corrected.

Vitamin D, Acute Respiratory Infection & Asthma – Seven clinical trials that examined the effects of vitamin D in preventing acute respiratory infections (ARI) in childhood were reviewed (3). While the reviewers found no reduction in ARI in healthy kids, children with asthma were 74% less likely to experience worsening of their asthma symptoms.

Genetic Study Supports Link Between Vitamin D & MS Risk – A number of factors, both genetic and environmental, can influence the risk of developing multiple sclerosis (MS), and possibly the severity of the disease as well. Research increasingly points to inadequate blood levels of vitamin D as one of those risk factors.

A new study (4) in those genetically prone to low vitamin D adds weight to the idea that the vitamin plays a role in MS. The findings were based on the genetic profiles of about 14,500 people with MS and 24,000 healthy people serving as controls. Looking at those with and without the disease showed that those with the genetic susceptibility to low vitamin D were at least twice as likely to have MS. Whether improving vitamin D levels can delay or prevent MS onset merits further investigation according to the authors.

References

1. Dow C, et al. Vitamin C supplementation reduces ET-1 system activity in overweight and obese adults. 14th Inter Conf on Edothelin: Physiol, Pathophysiol and Therapeutics, Savannah, GA. Sept. 4, 2015.
2. Houston DK, et al. Delivery of a vitamin D intervention in homebound older adults using a Meals-on-Wheels program: A Pilot Study. J Am Geriatr Soc. Aug 16, 2015 [Epub ahead of print]
3. Xiao L, et al. Vitamin D supplementation for the prevention of childhood acute respiratory infections: a systematic review of randomised controlled trials. Br J Nutr. Aug 27, 2015 [Epub ahead of print]
4. Mokry LE, et al. Vitamin D and Risk of Multiple Sclerosis: A Mendelian Randomization Study. PLoS Med. 25;12(8): e1001866, Aug, 2015.

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In the news: Minerals Linked to Metabolic Syndrome: Omega-3s Slow Schizophrenia?

Background: Metabolic Syndrome

Metabolic syndrome is a cluster of risk factors that raises the risk of developing diabetes and cardiovascular disease. Risk factors associated with the syndrome can include high blood pressure, elevated triglycerides, low HDL cholesterol, and lots of fat in the abdomen and waist area.

Metabolic syndrome is becoming more common due to the rise in obesity rates among Americans. According to the National Institutes of Health, metabolic syndrome may one day overtake smoking as the leading risk factor for heart disease.

Weight loss and exercise are our biggest weapons in the fight against metabolic syndrome. Results of a new study (1) suggest that higher intakes of calcium and magnesium may also modestly reduce the risk for this syndrome.

Calcium & Magnesium Linked to Lower Risk

Using dietary data from over 9,000 participants in the National Health and Nutrition Examination Survey, researchers from Case Western Reserve University tested the theory that higher intakes of the two minerals could decrease the risk of metabolic syndrome in men and women. The study measured blood triglycerides, HDL cholesterol and blood sugar as markers of the condition.

The investigators found that women who met the RDA for both calcium (1000-1200 mg daily) and magnesium (320 mg daily) had the greatest reduction in risk – a 41% risk reduction.

For men, consuming slightly higher amounts than the RDA for magnesium (400-420 mg/day) and calcium (1000-1200 mg/day) lowered the odds of metabolic syndrome by about 26% compared to men in the lowest intake group.

How might these two minerals affect the metabolic syndrome? Experimental studies have shown that a higher ratio of calcium to magnesium inside cells – which can be influenced by a diet high in calcium and low in magnesium – may lead to hypertension and insulin resistance. The authors of the study, however, point out that the mechanisms by which the two minerals may be working – as well as the gender differences they and others have observed – warrant additional research.

The take home message: make sure you’re getting sufficient magnesium by eating foods rich in this mineral: dark leafy greens, nuts, seeds, fish, beans, whole grains, avocados, yogurt, bananas, dried fruit, dark chocolate, and more. At the same time, meet the recommended daily allowance for calcium, with no need to over consume. A cup of milk offers about 300 mg of calcium, as does 8 oz. of yogurt and about 1.5 oz. of cheddar cheese. Kale, tofu and beans offer a bioavailable source of calcium too. Bon Appétit!

Omega-3s May Slow Schizophrenia

Schizophrenia usually starts in the first 20-30 years of life, with minor delusions and paranoid thoughts often occurring in the teenage years or younger. But only about 1/3 of those with these early symptoms eventually develop psychosis (being out of touch with reality), according to a report in the New Scientist.

Because blood levels of the omega-3s have been observed to be lower in schizophrenia patients than healthy controls, Australian researchers tested the effects of fish oil in a small number of people (aged 13-25) in a 3-month randomized trial, then continued to follow the participants after the trial ended.

After 7 years of follow-up, the researchers report that the majority of the individuals from the omega-3 group did not show severe functional impairment and no longer experienced the mild, earlier psychotic symptoms at follow-up (2). Only 10% of the fish oil group developed schizophrenia, compared with 40% of placebo-takers. If these findings hold up in larger trials, omega-3s may hold promise for those with this mental illness.

References

1. Moore-Schiltz L, et al. Dietary intake of calcium and magnesium and the metabolic syndrome in the National Health and Nutrition Examination (NHANES) 2001–2010 data. Br J Nutr. Epub Aug 11, 2015.
2. Amminger GP, et al. Longer-term outcome in the prevention of psychotic disorders by the Vienna omega-3 study. Nature Comm 6/Article no. 7934, Epub Aug 11, 2015.

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In the news: Interaction between Omega-3s & B-Vitamins in Brain Health

Age-Related Brain Shrinkage or Atrophy

With age our brains tend to shrink in size – a normal process that scientists refer to as age-related brain atrophy. Brain volume becomes smaller, with a loss of nerve cells and the connections between them.

The rate at which the brain shrinks is often higher in those who suffer cognitive or mental decline. This accelerated rate of brain atrophy is characteristic of people with mild cognitive impairment (MCI) who go on to develop Alzheimer’s disease. About 16% of people over 70 years of age have MCI, and roughly half of them will develop Alzheimer’s.

Omega-3s, B-Vitamins & Cognition

The results of some studies suggest that the omega-3 fatty acids may help preserve brain volume and cognition [see Nov, 2014 issue of Staying Healthy]. But so far the evidence is mixed, with some studies suggesting benefit for those with MCI or early/mild Alzheimer’s, and others finding none. The same can be said of the evidence overall for the B vitamins: intervention studies with B vitamins have yielded both disappointing and promising results in these patients.

One study with encouraging findings, the 2-year long VITACOG trial, found that high dose B vitamin (folic acid, B6 and B12) supplementation significantly slowed the increased rate of brain atrophy in older individuals with MCI, compared to treatment with placebo (1).

The VITACOG trial, published in 2010, also found that the participants’ response to the B vitamin supplement was related to their blood levels of homocysteine at the study’s start. High levels of the naturally occurring amino acid homocysteine is a risk factor for brain atrophy, MCI and dementia, and the B-vitamins can lower blood concentrations of homocysteine.

Omega-3s & the B-Vitamins: Better Together?

Researchers with the Oxford Project to Investigate Memory and Ageing (OPTIMA) at Oxford University recently took another look at data from the VITACOG trial. Their findings suggest that the ability of the B vitamins to slow down brain shrinkage may depend on having an adequate supply of EPA and DHA.

The analyses of data from VITACOG showed that participants with the highest blood levels of the omega-3s at the study’s start (and assigned to the B vitamin group) had a significantly slower rate of atrophy – about 40% slower compared to those getting placebo (2).

In contrast, the B vitamin treatment had no significant effect on the rate of atrophy among participants with low initial blood levels of omega-3s. Having higher baseline omega-3 levels did not slow the rate of atrophy in placebo-takers.

According to the authors, the effect of B vitamins on brain atrophy rates seems to depend on pre-existing omega-3 blood concentrations. And this might help explain why some B vitamin trials on brain function have not produced favorable results.

The findings – which need to be confirmed – also suggest that elevated homocysteine levels (which are lowered by B vitamins) also determine the effects of omega-3s in MCI and dementia, and may explain why some omega-3 trials have failed.

An editorial (3) accompanying this study points out that the omega-3s are thought to be protective by reducing free radical production and by stimulating the growth of axons and dendrites that project from, and connect nerve cells to one another. It appears that having sufficient levels of B vitamins and low homocysteine are required for the brain to optimally distribute and use the omega-3s.

References

1. Smith AD, et al. Homocysteine-lowering by B vitamins slows the rate of accelerated brain atrophy in mild cognitive impairment: a randomized controlled trial. Plos One 5:e1224, 2010.
2. Jerneren F, et al. Brain atrophy in cognitively impaired elderly: the importance of long-chain ω-3 fatty acids and B vitamin status in a randomized controlled trial. Am J Clin Nutr 102: 215-21, 2015.
3. Blasko I. Editorial. Interaction of ω-3 fatty acids with B vitamins in slowing the progression of brain atrophy: identifying the elderly at risk. Am J Clin Nutr 102:7-8, 2015.

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In the news: Statins & Nutrient Interactions

Rx for Statins Expected to Rise Significantly

A number of studies have demonstrated that a healthy lifestyle of eating well, exercising regularly, managing weight and not smoking can be an effective strategy to combat the risk of heart disease for many (1). Most recently, for example, it was reported that participants in a prospective study who most closely followed the Mediterranean way of eating were 47% less likely to develop heart disease over a 10-year period (2).

However, not everyone can stick to a healthy lifestyle, and others at high risk of having a heart attack or stroke may benefit from taking a statin medication (e.g. Crestor, Lipitor, Zocor and others).

According to a 2010 report from the National Center for Health Statistics, about 1 in 4 Americans over the age of 45 took statins. But in late 2013, new guidelines were issued by the American College of Cardiology and American Heart Association, which call for statin use in a broader range of healthier people, including those likely to have a stroke or heart disease as they age. As a result, prescriptions for statins are predicted to increase significantly over the next decade.

Previously, cholesterol-lowering drugs were generally reserved for patents judged to have a 20% chance of heart attack. The new guidelines not only recommend statins for those with high odds of suffering a heart attack or stroke in the short-term, but also for those with a 7.5% risk of suffering a stroke or heart attack over the ensuing 10 years. The guidelines also include those most at risk of ischemic stroke – the elderly, African Americans and women.

For those taking statins, the FDA issued advice in 2014 on the potential side effects associated with its use

Statin Interactions: CoQ10, Vitamin D, Vitamin K2?

In addition to interacting with certain other drugs, statins can also interact with some foods and nutrients. Grapefruit juice, for example, may decrease the ability of the liver to metabolize some statins and should not be consumed at the same time as the statin.

The nutrient Coenzyme Q10 (CoQ) is required by the mitochondria in cells to produce energy as ATP. CoQ is manufactured in the body along the same pathway that produces cholesterol. Statins inhibit one of the key steps in CoQ synthesis, and statin use has been associated with a reduction in blood and muscle tissue CoQ levels. A review on the CoQ-statin interaction notes that the elderly appear to be more susceptible to CoQ deficiency, as are the physically active who require the most efficient use of oxygen consumption by mitochondria (3).

Some researchers have recently proposed that statins may also interfere with the transformation of vitamin K1 (phylloquinone) to vitamin K2 (the menaquinones) in some tissues (4). Whether this potential interaction is of clinical importance isn’t known, but increasing dietary intake of vitamin K2 through fermented foods (e.g. cheese, curds, and natto) may be a good idea. Vitamin K2 is required by a protein thought to play a role in the prevention of age-related vascular calcification (see Staying Healthy, June issue).

A favorable interaction of vitamin D with statins is also a possibility according to a recent clinical trial of patients with high cholesterol given 2000 IU vitamin D or placebo daily along with a statin (5). At the end of 6 months, total cholesterol and triglycerides levels fell significantly more in the vitamin D group compared to placebo, and the effects were more pronounced for those with lower vitamin D levels at the study’s start. Results of a previous trial suggest that the lipid-lowering effects of vitamin D are limited to statin users, and likely due to a reduction in cholesterol absorption (6).

References

1. Chiuve SE, et al. Healthy Lifestyle Factors in the Primary Prevention of Coronary Heart Disease Among Men. Circulation 114:160-167, 2006.
2. Georgousopoulou E, et al. Adherence to Mediterranean is the Most Important Protector Against the Development of Fatal and Non-Fatal Cardiovascular Event. Presented at the American College of Cardiology's 64th Annual Scientific Session in San Diego, March 15, 2015.
3. Deichmann R, et al. Coenzyme Q10 and statin-induced mitochondrial dysfunction. Ochsner J 10:16-21, 2010.
4. Okuyama H, et al. Statins stimulate atherosclerosis and heart failure: pharmacological mechanisms. Expert Rev Clin Pharmacol 8:189–199, 2015.
5. Xiao FQ, et al. Effects of vitamin D on plasma liopids in stat-treated patients with hypercholesterolemia: A randomized placebo Controlled trial. Clin Nutr 34:201-06, 2015.
6. Kane L, et al. Vitamin D3 effects on lipids differ in statin and non-statin-treated humans. J Clin Endocrinol Metab 98:4400-09, 2013.

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In the news: ‘Multi’ Use & Risk of Stroke Death: Vitamin K Supports Artery Function

Multivitamin Use & Risk of Death from Stroke

February’s issue of Staying Healthy described the results of a study looking at multivitamin and mineral use among participants in the U.S. National Health and Nutrition Survey Exam. That study found a 35% reduction in the risk of death from cardiovascular disease (CVD) among women supplementing for over 3-years compared to non-users of multi supplements.

A link between multi use and CVD risk has again been reported – this time in research from Japan, published in the American Heart Association’s journal Stroke (1).

Over 72,000 men and women free from CVD at the study’s start were followed for about 19 years by investigators, who also collected information about the participants’ multivitamin supplement use.

After taking into account other factors affecting stroke risk, multi use was associated with a 20% lower risk of death from ischemic stroke – stroke that is caused by a clot blocking blood flow to the brain. The link was not seen for hemorrhagic stroke, which occurs when an artery in the brain leaks or ruptures. About 80% of all strokes are the ischemic type.

Among those who ate fruits and vegetables less than 3 times daily, multi use was linked to lower risk of dying from both total and ischemic stroke. This association was stronger for regular multi use vs. casual use.

Vitamin K Basics

There are two forms of fat-soluble vitamin K: K1 or phylloquinone, and vitamin K2, the menaquinones.

Our diet supplies Vitamin K1 through vegetables (green leafy ones especially), vegetable oils, and some fruits. Meat, dairy, and eggs contain low levels of K1 and modest amounts of vitamin K2. Fermented foods like natto (from fermented soybeans) have high levels of menaquinones, and fermented cheeses are a source as well. The bacteria in our GI tract also produce menaquinones, though it’s not clear how much is absorbed.

In plants, chlorophyll-containing cells tightly hold K1, making it less well absorbed than K1 from oils or supplements. Eating veggies at the same time as fat – dressing spinach salad with olive oil for instance – ups absorption of K1 from veggies.

Vitamin K is needed for blood to clot, and by a bone-building protein. It’s also required by a protein (matrix GLA-protein) that may play a role in the prevention of vascular calcification – the depositing of calcium in the middle or inner lining of arteries. One hypothesis is that inadequate vitamin K affects the function of matrix GLA-protein leading to greater artery calcification.

Vascular calcification is one risk factor for coronary heart disease because it reduces artery elasticity. Healthy, flexible arteries can expand and briefly store blood from each heartbeat to help move blood to all areas of the body. Both K1 and K2 are needed for good health, but recent population-health studies suggest that consuming adequate levels of K2 may be important for artery health.

K2 Findings from Observational Studies

Several population-health studies published in the past decade have reported that higher intake of the mena-quinones (though not phylloquinone) is linked to lower coronary calcification or risk of coronary heart disease in women (2,3).

A recent 10-year follow up study also found that a higher intake of menaquinones and good vitamin K levels overall are associated with a lower occurrence of metabolic syndrome – a cluster of symptoms associated with a greater risk of CVD (4).

Note: If you take Coumadin, be sure to inform your doctor before increasing vitamin K intake through foods or supplements. Maintaining consistent intakes of vitamin K is important for this drug to work properly.

References

1. Dong J-Y, et al. Multivitamin use and risk of stroke mortality. Stroke. [Epub March 31, 2015].
2. Beulens JW, et al. High dietary menaquinone intake is associated with reduced coronary calcification. Atheroscler. 203:489-93, 2009.
3. Gast GCV, et al. A high menaquinone intake reduces the incidence of coronary heart disease. Nutr Metab Cardiovasc Dis 19:504-10, 2009.
4.  Dam V, et al. The association between vitamin K and the metabolic syndrome: a ten-year follow-up study in adults. J Clin Endocrinol Metab. [Epub Apr 2, 2015].

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Findings on Myopia Call for Action

Myopia Boom Seen in Many Parts of World

According to an article in the journal Nature, there has been a dramatic increase in myopia worldwide. Myopia now affects about 50% of young adults in the US and Europe – double the prevalence of a half century ago. Sixty years ago, 10–20% of the Chinese population was short-sighted, while up to 90% of teens are today. In Seoul, South Korea, a whopping 96% of 19-year-olds are myopic (1).

Can a Tendency for Myopia Be Inherited?

Looking for other myopia-related risk factors, scientists noted that the modern rise in myopia mirrored a trend for children in many countries to spend more time engaged in reading, studying or glued to computer and smartphone screens. It seemed biologically plausible that constant up close work could alter growth of the eyeball as it tries to focus close-up images exactly on the retina. While some believe that excess close work could influence myopia development, the association hasn't held up well over time. In 2007, a study turned attention to light exposure as a potentially important contributor. Following 500 eight and nine-year olds with healthy vision over 5 years, the study found that the only factor strongly associated with myopia risk was time spent outdoors. Subsequent studies seem to rule out physical activity as an explanation for the outdoors link, since similar activities done indoors didn’t afford protection. The outdoors does offer longer viewing distances, which could help counter too much close work. However, what seems to matter most is bright light exposure.

How Might Bright Light Be Protective?

How bright light may offer protection is not yet understood. The leading theory is that light triggers the release of dopamine in the retina, and that this neurotransmitter in turn blocks the elongation of the eye during development (2). Another explanation involves vitamin D, as sunlight stimulates the body’s production of this vitamin. It’s thought that vitamin D influences ocular growth through interactions with vitamin A. So far, some studies report that myopia is associated with lower vitamin D status in young adults, while others question low ‘D’ levels as an independent risk factor. Based on studies to date, one researcher estimates that children need to spend around 3 hours daily under light levels of at least 10,000 lux to be protected against myopia. This is about the level experienced when sitting under a shady tree, wearing sunglasses on a bright summer day. In contrast, a well-lit class-room is usually no more than 500 lux.

Diet and Diabetes

Another risk factor proposed is diet. The increasing commonness of myopia in countries that have adopted Western ways of eating – bigger portions with a higher glycemic index – has led to the hypothesis that insulin resistance affects growth factors influencing the shape of the outer layer of the eyeball. Some studies report that myopia is more common in diabetics than non-diabetics, and that myopia is more common than farsightedness in those with diabetes.

Bottom Line: While scientists sort out which factor or factors are important, all of these actions – sending kids outside, making sure they eat well, and insuring good vitamin D intake – have plenty of health benefits beside those for the eyes.

References

1. Dolgin E. The myopia boom. Nature 519:276-78, 2015.
2. Goldschmidt E & Jacobsen N. Review: Genetic and environmental effects on myopia development and progression. Eye 28:126-33, 2014.

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In the news: Alpha Lipoic, EPA & Weight Loss: The Sugar Debates

Trying to Shed Weight? Get the Basics Down First

There are effective ways to loose weight and keep it off and some approaches that just fall flat. Adopting the Mediterranean style diet works, for example. Fad diets don’t. Eating less, eating better and moving more – whether it’s simply walking, or working out in the gym – are also fundamental parts of the equation for successful, long-term weight maintenance.

Once a sound plan for dietary changes and physical activity is in place, there may be additional ways to enhance weight loss efforts, at least in the short term, according to results from a newly published study (1).

Alpha Lipoic Acid May Boost Weight Loss

Nutrition researchers from the University of Navarra in Spain conducted a double blind, placebo controlled trial examining the effects of supplemental omega-3 fatty acid EPA and alpha lipoic acid on weight loss.

Ninety-seven overweight and obese women, all on calorie-restricted diets, were randomly assigned to receive one of 4 different daily treatments: EPA (1.3 g), alpha lipoic acid (300 mg), both the EPA and alpha lipoic acid combined, or placebo for a 10-week period.

The control (placebo) group lost an average of a little over 11 lbs. due to the reduced calorie intake. Women in the EPA only group lost about the same as the controls. Women in the group supplemented with alpha lipoic acid alone dropped significantly more weight than the controls – on average, about 4 lbs more.

Those in the EPA + alpha lipoic acid group also lost more weight than controls (about 14 lbs. on average), although the difference didn’t quite reach statistical significance. The EPA supplements appeared to help offset the drop in levels of leptin, the satiety or ‘feeling full’ hormone, which normally occurs during weight loss. But the researchers also believe alpha lipoic acid’s effects on fat tissue may have been a major contributor to the study’s findings.

Evidence from animal studies suggests that alpha lipoic acid helps block the conversion of glucose to fatty acids for storage and stimulates fat breakdown. It also helps block the formation of fat cells (2).
The researchers conclude that alpha lipoic acid alone or with EPA may aid weight loss when cutting calories. They also emphasize the need for more studies to confirm these findings, explore whether the effects are short or long term, and to shed further light on how these nutrients work, apart and together.

Less Sugar, Better Health

The World Health Organization, or WHO, has issued guidelines calling for curtailing added sugar intake to 5-10% of daily calorie intake. It’s estimated that in the US children get about 16% and adults get about 13-15% of their calories from added sugars. WHO isn’t talking about naturally occurring sugars in milk, fruits and vegetables, but rather table sugar, sweets, and high-fructose or other sugars added to foods and drinks.

Recently, a review and meta-analysis of 39 clinical trials comparing the effects of sugar and other (non-sugar) carbs on blood pressure and blood fats, found that higher intake of sugars directly contributes to risk factors for heart disease, independent of their effect on body weight (3).

Some have criticized these findings as not strong enough to back the recommendations made by WHO. But it’s clear that excess sugar contributes to overweight and cavities, quite probably cardiovascular disease, and has also been linked to increased risk of ocular diseases such as AMD and cataract as part of a high glycemic index diet.

One reasonable approach is to work toward WHO’s goals by enjoying sweets less frequently, and working on cutting back on sugary foods and beverages rather than trying to eliminate them altogether. 

References

1. Huerta AE, et al. Effects of α-lipoic acid and eicosapentaenoic acid in overweight and obese women during weight loss. Obesity 23:313-21, 2015.
2. Carrier B & Rideout C. Review: Anti-obesity and lipid- lowering properties of alpha- lipoic acid. J Human Nutr Food Sci 1:1002, 2013.
3. Te Morenga LA, et al. Dietary sugars and cardiometabolic risk: systematic review and meta-analyses of randomized controlled trials of the effects on blood pressure and lipids. Am J Clin Nutr 100:65-79, 2014.

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In the news: Recent Resveratrol Research: Rethinking High Dose Supplementation

Reducing Calories, Increasing Lifespan?

Calorie restriction – reducing calories while maintaining adequate nutrient intake – has long been studied as a potential way to increase lifespan and reduce the risk of developing chronic diseases. So far, the two long-term studies in monkeys designed to test the effects of calorie restriction have produced seemingly contradictory results.

One of the studies reported last year that calorie restriction appears to work in these primates, while interim results from the other study cast some doubts on the ability of calorie restriction to prolong lifespan. The second study is still ongoing, however, and researchers from both studies are working together to understand the discrepancies in their findings.

While the jury is still out on calorie restriction in monkeys – and humans, too, there are a number of ways that calorie restriction may be of biological benefit: a lower production of free radicals, less chronic inflammation and better repair of damaged DNA genetic material for instance.

Resveratrol May Mimic Calorie Restriction

Over the last decade, researchers have been looking for nutrients that can mimic the effects of calorie restriction. It was proposed that sirutins – proteins that regulate important biological pathways, might underlie some of the effects of calorie restriction by influencing processes like inflammation, energy efficiency, and resistance to stress.

In 2003, a Harvard team discovered that very large amounts of resveratrol might activate production of sirutin 1 in yeast (with additional findings published in 2013). Since the discovery, a few pilot studies conducted in humans – testing resveratrol at doses of 200 mg or higher – have reported some potentially beneficial effects, though results have sometimes been conflicting.

Fundamental New Findings on Resveratrol

Enter a research team from Scripps Research Institute who have proposed a new way that resveratrol might work. Their discovery (1), published in the journal Nature, suggests that resveratrol activates a protective stress response in human cells through a pathway involving an enzyme (TyrRS), and at concentrations much lower – just a fraction of the resveratrol levels tested in prior studies, including those focused on sirutins.

According to the authors, it’s conceivable that drinking moderate amounts of red wine would give a person enough resveratrol to spur a protective effect via this pathway. Red wines typically contain a range of 0.3-2.0 mg per 5 oz glass.

Resveratrol & Grape Extract in Heart Disease

Other researchers have looked at the effects of modest supplemental levels of resveratrol, finding that it works synergistically when combined with the other polyphenols found in grapes.

In one study, men with type 2 diabetes, stable hypertension and coronary heart disease were assigned to take 350 mg whole grape extract (lacking resveratrol), the extract with 8 mg added resveratrol, or placebo for 1-yr in a triple-blind randomized trial. Compared to placebo, grape extract lowered 1 pro-inflammatory compound (a cytokine), while the enriched extract lowered 3 additional key inflammatory compounds (2).

In an earlier year long trial (3), patients with type 2 diabetes or at high risk of heart disease and already on statins were assigned to the treatments described above. In contrast to placebo and grape extract, the resveratrol-rich extract significantly lowered markers of inflammation and improved patients’ fibrinolytic status (helping to prevent blood clots from growing and becoming a problem).

What’s the take home message? While the quest for a fuller understanding of how resveratrol works continues, sit back and enjoy some red wine!

References

1. Sajish M, et al. A human tRNA synthetase is a potent PARP-1 activating effector target for resveratrol. Nature [Epub ahead of print] Dec 22, 2014.
2. Tomé J, et al. One-year supplementation with a grape extract containing resveratrol modulates inflammatory-related microRNAs and cytokines expression in peripheral blood mononuclear cells of type 2 diabetes & hypertensive patients with coronary artery disease. Pharmacol Res 72: 69-82, 2013.
3. Tomé-Carneiro J, et al. One-year consumption of a grape nutraceutical containing resveratrol improves the inflammatory and fibrinolytic status of patients in 1° prevention of cardiovascular disease. Am J Cardiol 110: 356-63, 2012.

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In the news: ‘Multis’ May Cut CVD Risk in Women: Blueberries Improve Artery Health

Multi Linked to Lower CVD Mortality in Women

According to a 2013 Gallup poll, about half of Americans report regularly taking vitamin supplements. Using multivitamin and mineral supplements consistently appears to pay health dividends over time according to a new study (1) conducted by researchers at the National Institutes of Health’s Office of Dietary Supplements.

The research team analyzed data from the National Health and Nutrition Survey Exam (NHANES), looking at nearly 8,700 adults aged forty and older. The NHANES participants had no initial history of cardiovascular disease (CVD) and were followed for about 20 years.

When the investigators focused on how long multivitamin and minerals were used, they found a 35% reduction in risk of mortality from CVD among women supplementing for over 3-years compared to non-users.

This association held even after taking other factors into account that can affect CVD risk such as age, smoking, aspirin and alcohol use, blood lipids, blood pressure and HbA1c levels, a measure of blood sugar control.

The same relationship of multi-vitamin/ mineral use and risk of CVD death was not seen for men, which echoes the results of the Physician’s Health Study II (PHS II) – the only large-scale trial designed specifically to look at the long term effects of multi use on chronic disease in men. The PHS II reported a lower risk of cancer in multi users, although no CVD risk reduction.

Blueberries Serve Up Big Blood Pressure Benefits

When it comes to high blood pressure in the US, statistics are unsettling: 60% of Americans have hypertension or pre-hypertension (top number or systolic of 120-139 mm/Hg, diastolic of 80-89), which often leads to hypertension. That’s why new research (2) from Florida State University is welcome news.

The investigators report that daily blueberry consumption produced clinically significant reductions in both diastolic and systolic blood pressure of 5.1% and 6.3%, respectively, while improving the health of arteries in women with pre-hypertension and Stage 1 (mild) hypertension.

Of the 48 women randomly assigned to get 22 g of blueberry powder daily (equivalent to 1 cup of fresh berries) or placebo daily, those in the blueberry group had meaningful drops in blood pressure values at the end of 8 weeks. Those receiving placebo powder did not.

The blueberry consumers also had a reduction in arterial stiffness, which was not seen in placebo takers. When arteries stiffen and become less elastic, blood pressure tends to increase, especially systolic pressure.

Levels of nitric oxide, a potent dilator of vessels, increased over the course of the study only in the blueberry group. Nitric oxide relaxes blood vessel walls and lowers blood pressure. Deficits in the production or activity of nitric oxide can lead to dysfunction of the cells that line vessel walls, or endothelium, making arteries stiffer.

Along with other factors that can improve elevated blood pressure such as weight control, exercise, stress management, and moderating salt intake, adding blueberries may help prevent those with pre- or mild hypertension from developing full blown hypertension.

References

1. Bailey R, et al. Multivitamin-Mineral use is associated with reduced risk of cardiovascular disease mortality among women in the United States. J Nutrition. Jan. 7, 2015. [Epub ahead of print].
2. Johnson SA, et al. Daily blueberry consumption improves blood pressure and arterial stiffness in women with pre- and stage 1-hypertension: A randomized, double-blind, placebo-controlled trial. J Acad Nutr Diet. Jan 2, 2015. [Epub ahead of print].

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In the news: New Findings on Vitamin D & Fish Oil in Chronic Conditions

Vitamin D May Help COPD Patients

The last issue of Staying Healthy discussed research that reported benefits of maintaining normal blood levels of vitamin D for people with asthma. According to a new study funded by the UK’s National Institute for Health Research, avoiding low blood levels of this vitamin is also important for those with chronic obstructive pulmonary disease (COPD).

COPD is often a mix of chronic bronchitis and emphysema, which makes breathing difficult. Most people who have COPD are current or former smokers. Long-term exposure to other lung irritants – such as air pollution, chemical fumes, or dust – is also thought to contribute to COPD.

In this multi-center study (1), half of the participating 240 COPD patients were randomly assigned to take vitamin D supplements and half received a placebo for 1 year. The risk, severity and duration of disease flare-ups were compared between the two groups.

COPD patients with low blood levels of vitamin D (baseline concentrations below 50 nmol/L) benefited significantly from the supplements, with a more than 40% reduction in moderate to severe flare-ups. Participants who already had higher vitamin D status at the trial’s start did not experience that dramatic improvement, though all patients receiving vitamin D had a modest reduction in the severity and duration of flare-ups compared to placebo-takers.

Fish Omega-3s May Lower Risk of Deep Vein Clots

Venous thromboembolism (VTE) is a condition that includes both deep vein thrombosis (DVT) and pulmonary embolism. DVT is the formation of a blood clot in a deep vein – usually in the leg or pelvic veins. The most serious complication of a DVT is when the clot dislodges and travels to the lungs, becoming a pulmonary embolism. According to Johns Hopkins Medicine, deaths from VTE in the US and UK exceed those from AIDS, breast cancer, prostate cancer and traffic accidents combined.

Results of a large population-health study conducted in Norway link regular intake of omega 3s from fish and fish oil with a reduced risk of VTE (2). The researchers collected and analyzed data from more than 23,600 people over an average 16-year period. They found that eating 3 or more servings of fish weekly was associated with a 22% lower risk of VTE compared to consuming 1-2 servings per week.

Adding fish oil to this dietary regimen increased the apparent benefits, with a 48% risk reduction compared to those eating fish fewer than twice weekly and not taking omega 3 supplements. This promising association now needs to be tested in clinical trials.

Omega-3s Impact High Blood Pressure

Hypertension is common in the US, and millions more have high blood pressure and don’t know it or have pre-hypertension – slightly elevated levels that could lead to hypertension. Results of a meta-analysis (3), which included 70 controlled trials, suggest that consuming omega 3-rich foods or supplements could reduce high blood pressure.

The strongest effects of the omega fatty acids EPA and DHA were seen among people with elevated blood pressure who were not being treated for the condition. The average reductions in systolic pressures (the top number in blood pressure values) and diastolic pressures (the bottom number) were 4.51 mm Hg and 3.05 mm Hg, respectively.

For perspective, studies in people with untreated hypertension show that reducing salt intake decreases systolic pressure by 2-8 mm Hg, alcohol by 2-4 mm Hg, and that increasing physical activity reduces systolic values by 4-9 mm Hg. Since blood pressure tends to rise with age, a healthy lifestyle may help some people delay or prevent this increase.

References

1. Martineau AR, et al. Vitamin D3 supplementation in patients with chronic obstructive pulmonary disease (ViDiCO): a multicentre, double-blind, randomised controlled trial. Lancet Respir Med, Published online Dec 1, 2014.
2. Hansen-Krone I, et al. High fish plus fish oil intake is associated with slightly reduced risk of venous thromboembolism: the Tromsø Study. J Nutr 144:861-67, 2014.
3. Miller P, et al. Long-chain omega-3 fatty acids EPA and DHA and blood pressure: a meta-analysis of randomized controlled trials. Am J Hypertens 27:885-96, 2014.

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In the news:Flavonoids & Women’s Health: Vitamin D in Diabetic Retinopathy

Certain Flavonoids Might Cut Ovarian Cancer Risk

According to the American Cancer Society, ovarian cancer accounts for only 3% of cancers among women yet causes more deaths than any other cancer of the female reproductive system. Smoking is associated with an increased risk of this cancer, and possibly obesity, but scientists have not been able to clearly identify other lifestyle or dietary risk factors that women can change to reduce ovarian cancer risk.

Flavonoids are nutrients found in many plant based foods and beverages including fruit, vegetables, tea, and wine. There are also many different types or ‘subclasses’ of Flavonoids found in the foods we eat.

Earlier studies have hinted at an association between several of these flavonoid subclasses and ovarian cancer risk, but only recently have food databases been developed that provide information on the full range of Flavonoids present in the diet.

Taking advantage of this information, researchers from UK and Harvard have examined the association of 6 flavonoid subclasses and their main food sources with the risk of epithelial ovarian cancer. The study (1) involved nearly 180,000 women in the original Nurses Health Study and the Nurses Health Study II. The women were followed for many decades and information on their diet was collected every 4 years.
 
While total intake of all Flavonoids was not linked with ovarian cancer risk, women consuming the highest amounts of two subgroups (flavonols and flavanones) had a modestly lower risk of 21-24%. The main sources of these flavonoid subgroups include tea and citrus fruits or juice. In this study, oranges, orange juice and black tea, followed by onions and apples, were the most common sources of these Flavonoids.

This finding has to be confirmed by future studies in order to learn whether the foods we choose could have an impact on ovarian cancer risk. But in the meantime, consuming a more plant-based diet that provides flavonoid-rich fruit, veggies and beverages is associated with better health overall.

Low Vitamin D Levels and Diabetic Retinopathy

People with diabetes are at a higher risk for developing diabetic retinopathy because high blood sugar levels can damage blood vessels in the eye’s retina.
 
In some people with diabetic retinopathy, blood vessels may swell and leak fluid leading to macular edema – something that can happen at any stage of diabetic retinopathy. In others, abnormal new blood vessels grow on the surface of the retina. The growth of these blood vessels signals a more advanced stage of the disease (proliferative diabetic retinopathy), which can lead to severe vision loss.

Some studies have reported low levels of vitamin D in diabetics, or that the percentage of patients with vitamin D deficiency increases with severity of diabetic retinopathy.

In the latest investigation, researchers in China divided over 1500 patients with type 2 diabetes into 3 groups: those with no diabetic retinopathy, those with non-sight threatening retinopathy, and patients with sight-threatening retinopathy. Patients with the more advanced stage of sight-threatening diabetic retinopathy had significantly lower blood levels of vitamin D and more vitamin D deficiency (20 ng/ml or less) than the other two groups (2).

After adjusting for other factors that could affect the study results, the researchers concluded that vitamin D deficiency is an independent risk factor for diabetic retinopathy and vision-threatening diabetic retinopathy.

Can maintaining better levels of vitamin D reduce the risk of developing type 2 diabetes? Can correcting deficiencies of this vitamin lower the risk of developing complications like diabetic retinopathy? There are no answers yet, though trials are underway to test these hypotheses.

References

1. Cassidy A, et al. Intake of dietary flavonoids and risk of epithelial ovarian cancer. Am J Clin Nutr [Epub ahead of print] Aug 20, 2014.
2. He R, et al. Vitamin D deficiency increases the risk of retinopathy in Chinese patients with Type 2 diabetes. Diabet Med [Epub ahead of print] Sept 3, 2014.

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In the news: Calcium & Colon Health: Fish Oil & Mental Function

Can Adequate Calcium Intake Support Colon Health?

A good deal of evidence suggests that drinking milk may decrease the risk of colorectal cancer, which is the third most commonly diagnosed cancer in the U.S.

While a number of nutrients found in milk – vitamin D, some fats and organic acids – could be affording some of the apparent protection, calcium is believed by many to be the major contributing factor since its content is so high in milk, and there are plausible ways it could be acting.

Despite this likelihood, the results of population-health studies and clinical trials testing the effects of calcium supplements on markers of colon health have been inconsistent.

To better understand the relationship between calcium and colorectal cancer risk, researchers at Harvard School of Public Health conducted a dose-response meta-analysis of 15 prospective observational studies looking at calcium intake and involving over 12,300 cases of colorectal cancer.

In this meta-analysis (1), the authors found calcium to be responsible for this protective effect, with every 300 mg increase in total calcium intake daily associated with an 8% decrease in risk. They also compared dietary with supplemental calcium intake, and found that both sources provide similar benefits.

Since the National Health and Nutrition Examination Survey estimates that the median daily calcium intake from food alone for people over 50 years of age is 650 mg, the meta-analysis findings suggest that supple-mental calcium could help offset dietary calcium gaps and contribute to risk reduction.

The researchers conclude that randomized controlled trials of calcium supplements with at least 10 years of follow-up are warranted in order to confirm a benefit of supplementation on colorectal cancer risk.

Fish Oil Linked to Better Cognitive Test Scores and Brain Volume

Researchers from Brown University took a retrospective look at the relationship between use of fish oil supplements, cognitive decline and brain atrophy in over 800 participants of the NIH-funded Alzheimer’s Disease Neuroimaging Initiative (2).

Older adults (229 cognitively normal individuals, 397 patients with mild cognitive impairment, and 193 patients with Alzheimer's disease) were assessed with neuropsychological tests and brain magnetic resonance imaging (MRI) every 6 months for a 4-year period. The researchers examined cognitive function and brain atrophy in those who reported routine use of fish oil supplements versus non-users.

Compared to non-users, fish oil use during follow-up was associated with better cognitive test scores. It was also linked with less atrophy (smaller volume with a loss of neurons and the connections between them), in critical areas of the brain used in thinking and memory. The benefits were seen only in those who were initially normal, and were not observed in those who were already mildly impaired or had Alzheimer’s. Another group that did not seem to benefit were people who carried the APOE-4, a genetic risk factor for Alzheimer’s.

The associations seen in this study suggest that fish oil use may help preserve brain volume and cognition in some individuals. But the evidence overall is mixed, with some studies suggesting benefit for those with mild cognitive impairment or mild Alzheimer’s, and others finding none. The inconsistency in findings highlights the need for further research to see if the omega-3 fats can influence brain function and structure as we age, and which groups might be the beneficiaries.

References

1. Keum N, et al. Calcium intake and colorectal cancer risk: dose-response meta-analysis of prospective observational studies. Int J Cancer 135:1940-8, 2014.
2. Daiello LA, et al. Association of fish oil supplement use with preservation of brain volume and cognitive function. Alzheimers Dementia June 18, 2014 [Epub ahead of print].

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In the news: Vitamin D & Asthma: ‘Med’ Diet for a healthier life

Can Vitamin D Help Fight Asthma?

In children and adults with asthma, low blood levels of vitamin D have been linked to poorer lung function, airways that narrow instead of relax, more frequent asthma attacks, and less responsiveness to the corticosteroid medications used to treat symptoms. Two recent studies have looked further at the relationship between this vitamin and asthma.

The first, a clinical study (1) called the VIDA trial, looked at whether giving very large doses of vitamin D could improve the clinical response to inhaled corticosteroids in adult asthmatics already using bronchodilators. These patients had symptoms and low blood levels of the vitamin.

vitamin D treatment did not significantly reduce initial treatment failures compared to placebo. However, they saw a 12% decrease in overall treatment failures and a 20% reduction in the overall rate of asthma attacks for each 10 ng/mL increase in vitamin D levels.

In the second study (2), researchers examined some 300,000 people whose vitamin D blood levels had been measured. Over 21,000 of those people were found to have asthma.

While blood levels of vitamin D were not associated with an initial diagnosis of the disease, low levels were associated with the number of asthma attacks and the severity of those attacks. The lower the level of vitamin D, the greater the chance of having recurring asthma attacks. Among those with poor vitamin D levels, the odds for having an asthma attack were 25% higher than people with levels in the normal range.
 
What’s the take home message? Preventing low vitamin D levels is no magic bullet for those with asthma, but it can give them a better chance of controlling symptoms and managing their disease.

Benefits of the Med Diet are Long Lasting

Overall, those who adopt the Mediterranean style of eating (‘Med diet’) are likely to have a much lower risk of developing life-threatening and chronic disease than those who don't. Scientific evidence for the health benefits of the Med diet continues to grow, with the latest study from UK-based researchers showing that the benefits can be long lasting (3).

The endothelium is a thin membrane that lines the inside of the heart and blood vessels, and a healthy endothelium can fully dilate when needed. Having good endothelial function and healthy small blood vessels (micro-vascular integrity) is thought to reduce the risk of cardiovascular disease. The function of the endothelium and small vessels declines as we age.

In a previous study, the authors looked at healthy people 50+ for an 8-week period. One group was given a moderate exercise regimen and encouraged to follow a Med- style diet by consuming more fruit, vegetables, nuts, olive oil and oily fish. Participants in the other group were assigned to exercise alone.

At study’s end, the Med diet plus exercise group was found to have more vascular health improvements than those exercising only and, in fact, the age-related decline in endothelial and small vessel function was reported to be reversed in the combination group.

In the new study, a subgroup of participants from the original study again underwent tests to assess endothelial and small vessel function one year later. The original improvements seen with the 8-week exercise and Med diet were still evident, a year after the initial study.

This suggests that a brief intervention combining a Med-style diet with exercise promises long-term health benefits. It also suggests that adopting and sticking with this style of eating and exercising – even walking – can pay big dividends over a lifetime.

References

1. Castro M, et al. Effect of vitamin D3 on asthma treatment failures in adults with symptomatic asthma and lower vitamin D levels: The VIDA Clinical Trial. JAMA; 311:2083-91, 2014.
2. Confino-Cohen R, et al. Vitamin D, asthma prevalence and asthma exacerbations: a large adult population-based study. Allergy; Epub Oct 3, 2014.
3. Klonizakis M, et al..Long-term effects of an exercise and Mediterranean diet intervention in the vascular function of an older, healthy population. Microvasc Res; Epub Aug 7, 2014.

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In the news: Magnesium for Active Women: Alpha lipoic acid & Vision in Diabetes

Magnesium Benefits Active Women

Daily supplements of magnesium combined with a mild fitness program, improves the physical performance of mature, Italian women, according to a newly published study from the University of Padua.

The findings are clinically important for American women too, as surveys report that the majority of adults fall short in meeting recommended intakes of magnesium – a mineral important for strong bones, muscle function and the production of energy.

In the 3-month trial (1), healthy older women attending a light fitness program were randomly assigned to receive either 300 mg of magnesium (as oxide) or a placebo daily. The participants, whose average age was 71.5 years, took a battery of tests (the Short Physical Performance Battery or SPPB) at the beginning and end of the study.

Compared to the placebo group, women in the magnesium group had a significantly improved SPPB score. The benefits were even more pronounced in women with initial magnesium intakes below the RDA.

The magnesium-takers were able to walk faster and had stronger legs and better endurance as measured by 4 meter walking speed and the number of times they were able to stand up and sit down from a seated position (the “chair stand time” test). Both of these tests are key indicators of age-related decline in muscle mass and predictors of developing disabilities with age.

Alpha lipoic acid May Aid Vision in Diabetes

One potential complication faced by those with diabetes is diabetic retinopathy, caused by damage to the small blood vessels of the eye’s retina. Oxidative stress and inflammation have been implicated in the development and progression of diabetic retinopathy, leading some researchers to test whether various antioxidants might be of help in the condition. Investigators from the Department of Ophthalmology at the Medical University of Gdansk in Poland were prompted to explore the effects of the antioxidant alpha lipoic acid because it has been previously shown to be of benefit in experimental animal models of diabetic retinopathy.

The researchers chose to measure the effects of alpha lipoic acid on contrast sensitivity in the eyes of type 1 and type 2 diabetic patients, many of whom had early stage (non-proliferative) diabetic retinopathy. Visual acuity, which evaluates sharpness of vision, is often used to assess overall vision: it’s the eye chart with a large "E" at the top we’re asked to read when visiting the eye doctor.

Contrast sensitivity – the ability to see objects that may not be outlined clearly or that do not stand out from their background – can also be important in evaluating vision. If contrast sensitivity is impaired it can affect vision even when visual acuity is normal.

Three groups of people participated in this exploratory study (2): those with type 1 diabetes mellitus (T1DM); those with type 2 (T2DM), and healthy controls. Participants within each group were randomly assigned to receive 300 mg of alpha lipoic acid daily or no supplements for a 3-month period.

The researchers report that contrast sensitivity remained stable in the group of patients with T1DM and improved in the T2DM group receiving alpha lipoic acid, while contrast sensitivity significantly declined in non-supplemented T1DM and T2DM groups. Among healthy supplemented volunteers, minor improvement (at only one spatial frequency) was observed.

The results are promising but preliminary, and larger well-designed trials should be conducted to see whether alpha lipoic acid can truly benefit the vision of those with diabetes.

References

1. Veronese N, et al. Effect of magnesium supple-mentation on physical performance in healthy elderly women involved in a weekly exercise program: a randomized controlled trial. Am J Clin Nutr, July 9, 2014 [Epub ahead of print].
2. Gebka A, et al. Effect of the administration of alpha-lipoic aid on contrast sensitivity in patients with type 1 and type 2 diabetes. Mediators Inflamm, Volume 2014:1-7 (Article ID 131538).

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In the news: Vitamin C & Artery Health, Lutein & Brain Function

Vitamin C Especially Vital for Those at Risk of CVD

The results of a new review suggest that vitamin C provides benefits for certain groups of people. In the study (1), British scientists report that vitamin C in doses higher than 500 mg daily may improve functioning of the inner lining of blood vessels (the endothelium), and support heart heath for those who need it most – those with diabetes, atherosclerosis and heart failure.

The endothelium helps maintain the elasticity of blood vessels and helps regulate the activity of white blood cells (neutrophils) that are a key component of the immune system. Impaired endothelial function can lead to arteries that are not as supple, raising the risk of hypertension. Poor endothelial function can also lead to arteries that are chronically inflamed.

Forty-four randomized controlled trials involving more than 1,100 participants were included in this meta-analysis and systematic review evaluating the effect of supplemental vitamin C on endothelial function.

The meta-analysis showed a significant positive link between the dose of vitamin C and improvement in endothelial function. The effect of vitamin C supple-mentation also appeared to be dependent on health status, with stronger effects seen for those who are more at risk for cardiovascular disease.

These beneficial effects may be due to vitamin C’s ability to help keep oxidative damage and vessel inflammation in check, as well as increasing the availability of nitric oxide, a compound that dilates vessels and helps maintain endothelial function.

Role for Lutein in Supporting Brain Function?

One exciting topic discussed at the International Carotenoid Society (ICS) meeting held this July, was the potential role of the carotenoids lutein and zeaxanthin in cognitive function, e.g. the process of knowing, perceiving, and remembering.

lutein and zeaxanthin are the only two carotenoids that cross the blood barrier of the retina to form the eye’s macular pigment. Studies have found that these two carotenoids also accumulate in the brain in preference to other carotenoids in our diets such as alpha and beta-carotene, lycopene and beta-cryptoxanthin.

The concentration of lutein and zeaxanthin in the eye’s macula corresponds to the concentration of these carotenoids in brain tissue. So researchers now consider macular pigment density to be a ‘bio-marker’ of lutein / zeaxanthin levels in the brain (2). This is intriguing because a significant correlation between macular pigment density and measures of cognitive function has been seen in studies of older individuals (3).

lutein / zeaxanthin have antioxidant and anti-inflammatory effects, and help stabilize cell membranes – actions which are important for healthy cognition. The Center for Nutrition, Learning and Memory has been established at the University of Illinois to better understand exactly how and where these carotenoids work in the brain.

Results of the cognitive function sub-study from the AREDS2 trial were announced at the ICS meeting. While the study found no association between lutein / zeaxanthin supplementation and cognitive function overall, the researchers have not yet ruled out the possibility that supplements made a difference for those whose dietary intake of these carotenoids was low at the study’s start.

In contrast to the AREDS2 findings, several small, exploratory studies have reported promising results. In a 4-month double blind, placebo controlled study, verbal fluency scores improved in older women given supplemental lutein, DHA or both nutrients. Memory scores and rates of learned also improved in the combined treatment group (4).

References

1. Ashor AW, et al. Effect of vitamin C on endothelial function in health and disease: A systemic review and meta-analysis of randomized controlled trials. Atherosclerosis 235:9-20, 2014.
2. Johnson EJ. Review. A possible role for lutein and zeaxanthin in cognitive function in the elderly. AJCN 96(suppl):1161S-5S, 2012.
3. Vish-wanathan  R, et al. Macular pigment optical density is related to cognitive function in older people. Age Aging 43:271-5, 2014.
4. Johnson EJ et al. Cognitive findings of an exploratory trial of DHA and lutein supplementation in older women. Nutr Neurosci 11:75-83, 2008.

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In the news: Green Tea & DNA Repair; Magnesium & Diabetes Risk

Green Tea May Boost DNA Repair

Collective evidence from over the past two decades suggests that green tea compounds are protective, and that drinking green tea supports good health. A small but interesting study conducted by Chinese researchers has shed some light on at least one way that green tea may work on the cellular level.

DNA, the spiral structure within cells that carries our genetic inheritance, can be damaged by environmental factors such as air pollution and tobacco smoke as well as by the free radicals generated during normal metabolism. The resulting damage, if not repaired, can lead to mutations and possibly disease. However Mother Nature has provided mechanisms that help fix DNA damage, and a number of enzymes are involved in this process.

In the new study, investigators tracked the activity of DNA repair enzymes in white blood cells (lympho-cytes) right after the study participants drank a cup of green tea, and after a week of drinking two cups daily. The control treatment was drinking water.

Compared to the control period, the researchers found that two enzymes were more active after drinking tea – one that’s important for fixing DNA damage from oxidation, and another that protects DNA from this kind of damage. Thirty percent less DNA damage was observed an hour and two hours after consuming a cup of tea, and in samples collected after the 7 days of tea consumption (1).

Boosting repair enzyme activity appears to be one way that green tea helps protect DNA. A next step might be to determine whether green tea has the same effects in other types of cells as it does in lymphocytes.

Magnesium May Help Stave Off Diabetes

Many population health studies have linked higher magnesium intakes with a reduced risk of developing type 2 diabetes. Now, the findings of a newly published study that followed over 2,500 middle-aged Americans for seven years, seems to affirm these observations.

Healthy people who consumed the most magnesium lowered their risk of developing metabolic impairments such as elevated glucose or circulating insulin levels that can lead to pre-diabetes and potentially to a diagnosis of type 2 diabetes (2).

Among participants who were already metabolically impaired, those with the highest intakes of this mineral were significantly less likely to develop type 2 than those consuming the least.

When looking at the combined groups (people with and without metabolic impairments at baseline), the highest consumption of magnesium cut the risk of developing diabetes in half.

Many magnesium-rich foods are rich in fiber too, and fiber also contributes to blood glucose control. When the researchers took fiber into account, fiber intake seemed to be partially responsible for the observations seen in the originally healthy group. However, it didn’t substantially affect results in the group with existing impaired metabolism. The researchers conclude that magnesium may be particularly beneficial in reducing the risk of diabetes among those who are at high risk.

These findings make good biologic sense since low magnesium levels can affect the ability of cells to respond to insulin – the hormone that enables cells to take up glucose from the blood stream. The findings are also important because large national surveys indicate that marginal magnesium deficiency may be relatively common in the US.

References

1. Ho CK, et al. Effects of single dose and regular intake of green tea (Camellia sinensis) on DNA damage, DNA repair, and heme oxygenase-1 expression in a randomized controlled human supplementation study. Mol Nutr Food Res June 2014 [Epub ahead of print].
2. Hruby A, et al. Higher magnesium intake reduces risk of impaired glucose and insulin metabolism and progression from prediabetes to diabetes in middle-aged Americans. Diabetes Care 37:419-27, 2014.

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In the news: Folic acid & Glaucoma, Overall Diet & AMD

Pseudoexfoliation, a Form of Glaucoma

Open angle glaucoma can develop in some patients with a condition called exfoliation syndrome. In this condition, there is an abnormal build-up of protein and exfoliation material that can clog the eye’s drainage system. Some people with exfoliation syndrome have higher eye pressures and faster disease progression than patients with classic open angle glaucoma.

EG, Homocysteine & Folic Acid: A Connection?

One possible risk factor for exfoliation glaucoma (EG) that has received a good deal of research attention is homocysteine. Homocysteine is a naturally occurring amino acid that can build up in blood due to dietary influences, genetics, and other causes.

High blood levels of homocysteine seem to enhance the formation of exfoliation material by contributing to vascular damage and oxidative stress. Researchers, in fact, have fairly consistently found elevated homo-cysteine levels in the blood, aqueous humor (fluid inside the front of the eye), and tears of people with exfoliation syndrome or EG.

Blood levels of homocysteine tend to be higher in people who eat a lot of animal protein and consume few fruits and leafy vegetables – sources of folic acid and other B vitamins that help keep homocysteine levels in the normal range.

Folic Acid & Risk for EG

Harvard researchers have conducted the first prospective study evaluating long-term B vitamin intake and risk for EG and suspected EG (cases of exfoliative syndrome who met criteria for other signs of glaucoma) in over 119,000 men and women followed for 20 years (1).

The participants were free of glaucoma to begin with, and their intake of the B-vitamins was updated over time. The researchers previously reported that higher intakes of folate and vitamins B6 and B12 are linked to lower levels of homocysteine. The authors now report that higher intake of total folate is associated with a lower risk for EG. The association was strongest for supplemental folic acid, which is more bioavailable than natural folate. (folate is the generic term for both naturally occurring folate in foods, and for folic acid, the vitamin form used in dietary supplements and fortified foods.)

According to the authors, their results support the idea that homocysteine plays a role in EG and that folate may be protective. They also stress the need for more research before firm conclusions can be drawn.

Does Overall Diet Affect the Risk for AMD?

The results of two new studies suggest that how we eat may well be a factor in staving off age-related macular degeneration (AMD). In the first US study (2), people who most closely followed a dietary pattern identified by higher intake of produce, whole grains and seafood (dietary pattern A) had a significantly lower risk of developing early AMD. A greater risk for early AMD was seen for those adhering most closely to a diet higher in red meat, processed meat, high fat dairy and refined grains (pattern B).

The risks associated with advanced AMD were even more pronounced: A 62% lower risk was seen for diets most closely matching pattern A compared to diets that matched up the least. People whose diets lined up the best with pattern B were about 3.7 times more likely to develop advanced AMD compared to those whose diets were the least well aligned.

The findings from the second study (3) conducted in Australia were fairly similar in terms of broad food consumption and risk of advanced disease. Diets high in fruits, vegetables, chicken, and nuts and diets low in red meat appeared to be associated with lower prevalence of advanced AMD.

References

1. Kang, JH, et al. A prospective study of folate, vitamin B6, and vitamin B12 intake in relation to exfoliation glaucoma or suspected exfoliation glaucoma. JAMA Ophthalmol 132:549-59, 2014.
2. Chiu C, et al. The relationship of major American dietary patterns to age-related macular degeneration. Am J Ophthalmol [Epub ahead of print, Apr 29, 2014].
3. Amirul I, et al. Dietary patterns and their associations with age-related macular degeneration: The Melbourne Collaborative Cohort Study. Ophthalmol [Epub ahead of print Feb 20, 2013].

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In the news: Lutein in Early AMD: Acid-Suppressors & B12

Lutein May Support Clearer Vision in Early AMD

The macula, located roughly in the center of the retina, is the area of the eye that allows sharp central vision. Lutein and zeaxanthin, known as macular pigments, help to protect the macula from harmful blue light and have anti-inflammatory properties that could be of benefit in the aging retina.

The density of macular pigment has been found to decline as we grow older, and low density appears to be a risk factor for age-related macular degeneration (AMD).

We usually hear about Lutein and zeaxanthin in the context of playing a possible role in AMD prevention, or in the context of slowing progression of the disease in those who already have intermediate to advanced stages and don’t consume enough Lutein and zeaxanthin. But could these nutrients have a role to play in the early stages of AMD?

To focus on that question, researchers from the UK and the Netherlands conducted a randomized placebo controlled clinical trial in patients with early AMD (1). Study participants were assigned to take 10 mg of Lutein daily or placebo, and were followed for a year.

Macular pigment density increased significantly in the Lutein group, while no change was seen for placebo. Visual acuity (a measure of clarity or sharpness of vision) didn’t change in the Lutein group as a whole, and worsened among placebo-takers.

Since about half the participants had normal or above normal sharpness of vision when the trial began, the researchers looked at those who started out with poor visual clarity. They found that Lutein did improve visual acuity among these patients. These promising, although preliminary, findings suggest that the potential role of Lutein in early AMD deserves greater attention.

“Acid Reducing” Drugs and Vitamin B12

Millions of Americans use acid-suppressing drugs called proton pump inhibitors (PPIs) for treating conditions such as heartburn, GERD, and peptic ulcers. Long-term use and high doses have been associated with an increased risk of bone fractures and infection with a bacterium called Clostridium difficile. A recent study suggests that users of acid-suppressing medications need to be aware of these drugs apparent effect on vitamin B12 as well.

vitamin B12, which plays a critical role in forming red blood cells and in brain and nervous system function, can be difficult to absorb for some. Stomach acid is required to release B12 from foods before it’s available to be absorbed. Older people are at greater risk for low B12 because stomach acid output declines with age.

A recent study (2) found that using PPIs for 2 or more years increased the risk of vitamin B12 deficiency by 65%. To a lesser extent, B12 deficiency was also associated with use of histamine-2 receptor antagonists (H2RAs) – another medication that slows the release of stomach acid.

The investigators found these associations when comparing nearly 26,000 patients diagnosed with vitamin B12 deficiency over a 14-year period, with about 184,000 patients without B12 deficiency.

Unlike protein-bound B12 in foods, the form in supplements and B12-fortified foods such as certain breakfast cereals isn’t dependent upon stomach acid to be bioavailable. So it’s a good idea for people taking acid-reducing medications to get B12 from supplements and/or fortified food sources. The Institute of Medicine, in fact, recommends that all adults over the age of 50 obtain the RDA for vitamin B12 from supplements or fortified foods.

For those who have taken these medications for extended periods of time, it may also be wise to speak with a physician about having a blood test to determine B12 blood levels and to discuss the benefits and risks of these medications.

References

1. Murray IJ, et al. Lutein supplementation over a one-year period in early AMD may have a mild beneficial effect on visual acuity: the CLEAR study. Invest Ophthalmol Vis Sci 11:1781-88, 2013.
2. Lam JR, et al. Proton pump inhibitor and histamine 2 receptor antagonist use and vitamin B12 deficiency. JAMA 310:2435-42, 2013.

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Brain Health Part 2: Culinary Culprits to Avoid

Poor Dietary Choices and Mental Function

The previous issue of Staying Healthy (Brain Health Part 1) discussed recent insights into brain protective practices and key strategies for boosting mental function.

This issue focuses on the types of foods that emerging research suggests we should limit or avoid. For the most part they’re the usual suspects associated with risk for cardiovascular disease – unhealthy fats, refined sugars and junk foods, and these dietary habits appear to undermine optimal mental functioning as well. A recent article in Medscape aptly refers to them as potential “culinary culprits” (1).

Avoid Trans Fats to Help Support Good Mood

If you haven’t yet tuned into checking food labels for their trans fatty acid content, now’s a good time to start. It’s well known that these fats pose a risk to the heart, but consistent intake of these fats may also raise the risk for depression. Depression, which affects about 121 million people worldwide, can negatively impact mental clarity.

Looking at the diets of over 12,000 people who were free of depression at the study’s start, researchers in Spain found a robust link between higher intake levels of trans fatty acids and a diagnosis of depression (2).

The way in which trans fats can be harmful to the heart and the brain may be similar, according to the research team. Chronic inflammation and impaired functioning of the endothelium (blood vessel lining) are frequently seen in patients with depression. Pro-inflammatory changes and endothelial dysfunction are also responsible, in part, for the detrimental effects of trans fats in cardiovascular disease.

Trans fats are also thought to raise levels of “bad” LDL cholesterol and reduce “good” HDL cholesterol levels – changes that may negatively impact blood flow to the brain over time.     

Trans fats are created during a process called hydrogenation, which stabilizes polyunsaturated oils to prolong their shelf life and to keep them solid at room temperature. Hydrogenated fats are found in stick margarine, fast foods, baked goods (donuts, cookies, crackers), processed foods, and fried foods.

Limit Fast Foods & Refined Sugar

The same Spanish research team, this time studying nearly 9,000 adults, reports a strong link between “junk food” and cognitive deficits, namely depression. Study participants who frequently consumed fast food were 40% more likely to develop depression than those who mostly steered clear of burgers, pizza, sausage, processed pastries, and the like (3).

The high level of trans fatty acids in fast foods is likely an important contributor to the study’s findings. In addition, people who consistently eat fast food and empty-calorie sugary foods often do so at the expense of foods rich in brain-protective nutrients such as the fats in oily fish and nuts, the B-vitamins, and other plant-derived nutrients.

Higher intake of simple sugar has also been linked to lower mental function and the risk of developing mild cognitive impairment (4,5).

In short, growing evidence suggests that adopting better eating habits may not only support good health overall, but better brain function as well.

References

1. Melville NA. Culinary culprits: Foods that may harm the brain. Medscape Medical News Jan, 30, 2014.
2. Sanchez-Villegas A, et al. Dietary fat intake and the risk of depression: the SUN project. PLoS One. 2011; 6(1): e16268.
3. Sanchez-Villegas A, et al. Fast food and commercial baked good consumption and the risk of depression. Pub Hlth Nutr 15:424-32, 2012.
4. Ye X, et al. Habitual sugar intake and cognitive function among middle-aged and older Puerto Ricans without diabetes. Br J Nutr 106:1423-32, 2011.
5. Roberts RO, et al. Relative intake of macronutrients impacts risk of mild cognitive impairment or dementia. J Alzheimers Dis 32:329-39, 2012.

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Brain Health Part I: Tips for Keeping Your Mind Sharp

Brain Protecting Basics and New Research

Studies have shown that some basic health habits can help prevent cognitive decline and reduce the risk of dementia: Healthy eating, staying physically active, not smoking, sleeping well, limiting alcohol intake, and maintaining good social connections. Challenging the brain with mental exercise is also thought to help maintain brain cells and stimulate signaling between them. This issue of Staying Healthy takes a look at recent insights into brain protective practices and key strategies for boosting mental function (part II will focus on culinary culprits in brain health).

Get a Good Night’s Sleep. 

All of us can attest to the refreshing feeling that a good night’s sleep provides (and to the mental fuzziness that can result from inadequate or poor quality sleep). But in addition to renewing energy and consolidating memories, brain-protective processes with long-term implications also appear to be at work when we sleep.

In a series of animal studies (1), researchers found that while asleep the brain is busy cleaning out cellular “trash” and toxins that accumulate during waking hours, including proteins (beta amyloid and tau) associated with Alzheimer’s and other types of dementia. While more research needs to be conducted in humans, it appears that insufficient or disturbed sleep impairs the brain’s ability to get rid of this neural waste. Experts suggest 7-9 hours of sleep nightly.

Choose Brain-Boosting Beverages.

Coffee, green tea and cocoa seem to top the list. Coffee (caffeinated) may improve memory according to new findings (2). While caffeine is known to support mental performance, it has been thought to have little or no effect on longer-term memory retention. Researchers showed that volunteers given caffeine right after standard recognition memory tasks, per-formed better at similar tasks the next day versus those given a placebo. 

Two cups of cocoa daily for a month was shown to improve cognitive function and blood flow in the brain among those with impaired neurovascular coupling (3 )– a measure of blood flow in the brain in relation to nerve cells. Other studies have shown that flavonols found in cocoa help maintain the elasticity of blood vessels, which is important for normal brain blood flow.

A number of recent studies are stimulating interest in green tea’s potential to protect brain cells and promote brain performance.  In one study (4), researchers used magnetic resonance imaging (MRI) to observe the brains of people during tests of working memory – memory that allows the brain to process and store information at the same time. Compared to those getting a placebo, participants given green tea extract had increased activity in an area of the brain where working memory is processed.

Go Mediterranean

Many individual nutrients contribute to maintaining good mental function as we age, including B-vitamins, antioxidants, flavonoids and omega-3 fatty acids. But examining the influence of an overall eating pattern on cognition instead of a single or a few nutrients allows us to study the synergy among these nutrients.

One way of eating that emphasizes brain-supporting nutrients is the Mediterranean diet (Med diet). It includes olive oil as the main dietary fat, and is high in plant-based foods (fruits, nuts, vegetables, beans and minimally processed or whole grains). It also includes ample amounts of fish and seafood, while dairy and meat are eaten more sparingly.

The results of a recent randomized trial found that the Med diet improves long-term mental function in older individuals (5). Study participants assigned to a Med diet plus extra virgin olive oil or nuts fared significantly better on a battery of cognitive tests after 6 ½ years than did those on a low fat diet.

References

1. Xie L, et al. Sleep drives metabolite clearance from the adult brain. Science 342:373-7, 2013.
2. Borota D, et al. Post-study caffeine administration enhances memory consolidation in humans. Nature Neurosci 17:201-3, 2014.
3. Sorond FA, et al. Neurovascular coupling, cerebral white matter integrity, and response to cocoa in older people. Neurol 81(10):904-9, 2013.
4. Borgwardt S, et al. Neural effects of green tea extract on dorsolateral prefrontal cortex. Eur J Clin Nutr  66:1187-92, 2012.
5. Martinez-Lapiscina EH, et al. Mediterranean diet improves cognition: the PREDIMED-NAVARRA randomised trial. J Neurol Neurosug Psych 84:1318-25, 2013. 

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Diet, Fats & Prostate Health: Trying to Unravel the Puzzle

Fats & the Prostate: Trying to Unravel the Puzzle

The research on dietary fats and prostate health has produced conflicting results and left many men wondering whether they should be avoiding some kinds of fats while eating more of others.

When it comes to intake of omega-3 fatty acids from fish, some studies have found no effect on prostate cancer while others suggest that consuming more might be protective. A study published in 2012 even raised the question of whether higher intake of DHA could be detrimental for men with high-grade prostate cancer. (This same study, however, reported that trans-fatty acids – the “bad” fats – were also linked to a lower risk of high-grade prostate cancer – a finding that contrasts with the available evidence and heightens doubts about the study’s findings overall).

All of these confusing results could mean that the relationship between fat and the risk of prostate cancer is complex.

Omega-3s and Prostate Cancer Research

Enter Dr. William Aronson and his colleagues from UCLA. These researchers are trying to shed some light on the effects of low fat diets and omega-3 fats, at least in men who already have prostate cancer.

Their latest study (1) (an analysis of an earlier study they conducted in men who underwent prostate removal), found that men assigned to eat a low fat diet and fish oil had lower levels of pro-inflammatory substances and lower cell cycle progression (CCP) scores than those eating a typical American high-fat diet.

The level of pro-inflammatory compounds is relevant because inflammation is thought to be a factor in prostate cancer development.  CCP score is a measure used to predict cancer recurrence, and lowering scores may help prevent this cancer from becoming more aggressive.

Heart-Healthy Diet May be Prostate-Healthy

A heart-healthy diet that reduces intake of carbs, animal fats and saturated fats, and replaces those calories with unsaturated oils (e.g. olive and canola) and nuts might benefit men with prostate cancer according to a team of Harvard and UC San Francisco investigators.

In their analysis of a large-scale observational study (2), this pattern of eating was associated with lower risk of death in men with prostate cancer that hasn’t spread beyond the prostate (non-metastatic).

These researchers also report that a Mediterranean style of eating was associated with decreased overall mortality in men diagnosed with non-metastatic prostate cancer (3). The Med-style diet is lower in animal fat and has more fats from olive oil, nuts and fish. (It’s also rich in tomatoes and tomato products – a source of the carotenoid lycopene, which has also been linked in some studies to prostate health). 

References

1. Galet C, et al. Effect of a low-fat fish oil diet on pro-inflammatory eicosanoids and cell cycle progression score in men undergoing radical prostatectomy. Cancer Prev Res 7:97-104, 2014.
2. Richman EL, et al. Fat intake after diagnosis and risk of lethal prostate cancer and all-cause mortality. JAMA Intern Med173:1318-326, 2013.
3. Kenfield SA, et al.  Mediterranean diet and prostate cancer risk and mortality in the health professionals follow-up study. Eur Urol [Epub ahead of print], Aug, 2013.

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Multi Use & Cataract Risk; Nutrients & Genetic Risk of AMD

2013 Findings for Nutrition & Ocular Health

Several studies with positive findings mark the end of 2013, emphasizing that dietary choices and smart supplementation can support our visual health.

The December issue of Staying Healthy covered two new studies: a meta-analysis suggesting the importance of consuming lutein and zeaxanthin to help forestall nuclear cataract (the most common type of age-related cataract), and a clinical trial which found that supplemental lutein, zeaxanthin and docosa-hexaenoic acid (DHA) improved macular pigment density in patients with early age-related macular degeneration (AMD).    

This issue highlights two additional studies published late last year that are worthy of mention. One examines the role of certain nutrients in people who inherit a high genetic risk of developing AMD (1), while the other is a large-scale trial of multivitamin use and cataract risk (2).

Fish, Lutein-Rich Foods Protective for AMD

In the first study, a team of researchers from Australia, the Netherlands and the US combined data from two large population studies, the Rotterdam Study and the Blue Mountains Eye Study – large studies where people were followed for 15 years. The team wanted to examine whether nutrients could influence AMD development or progression in people with a high genetic risk of AMD based on two major genes (CFH and ARMS2).

Looking at the interplay between nature (one’s genetic make-up) and nurture (diet and lifestyle choices) may provide a better understanding of why some people with genetic risk for AMD develop the condition, while others don’t. 

The results of their analysis suggest that greater consumption of lutein / zeaxanthin-rich foods and fish is protective against AMD in people with high genetic risk. Those with 2 or more risk alleles (different forms of a gene) who ate fish weekly were 46% less likely to have late AMD. 

The high-risk group also benefited from regular consumption of lutein and zeaxanthin rich foods. Those eating the most of these two carotenoids had a 22% to 25% lower risk for early AMD and any AMD, compared with those eating the least. These dietary associations were not seen in low risk groups – those with no risk allele or only one risk allele.

Even if you’re dealt a poor genetic hand, there are steps you can take to reduce your chance of developing AMD: include fish and green leafy vegetables in your diet, exercise and watch your weight, don’t smoke, and get regular eye exams. 

A Daily Multi Lowers Cataract Risk

Harvard researchers have reported the final results for cataract and AMD from the multivitamin part of the Physicians’ Health Study II (PHS II). PHS II was a long- term trial that included over 14,000 healthy middle-aged men, all physicians.

The multivitamin portion of the trial ended in 2011, and the researchers reported that taking a daily multi lowers the risk of cancer, though not cardiovascular disease. The trial also evaluated the effects of a multi on the prevention of eye disease (cataract and AMD), and cognitive function.   

The results showed that the multivitamin group had a significant 9% lower risk of cataract over the 11-year course of treatment. Although the risk reduction is modest, cataract is so common that even a modest reduction in risk would have a large public health impact. There was no significant benefit or harm of multivitamin supplementation on visually significant (later stage) AMD.  Still to be reported are the results for cognitive function and daily multi supplementation.

References

1. Wang Jie Jin, et al. Genetic susceptibility, dietary antioxidants, and long-term incidence of age-related macular degeneration in two populations. Ophthalmology Nov 28, 2013 [Epub ahead of print].
2. Christen WG, et al. A multivitamin supplement and cataract and age-related macular degeneration in a randomized trial of male physicians. Ophthalmology Nov 20, 2013 [Epub ahead of print].

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New Lutein, Zeaxanthin and Omega-3 Research

Lutein & Zeaxanthin Lower Cataract Risk

Lutein and zeaxanthin are believed to help protect the eye’s lens against cataract formation, but findings from epidemiologic studies haven’t always been consistent.

To shed more light on the relationship between these two carotenoids and age-related cataract, researchers conducted a meta-analysis1. This analysis combined the results of six separate high-quality population-health studies involving 42,000 participants.

The study found that participants eating the highest amount of Lutein and zeaxanthin would expect to have a 25% lower risk of nuclear cataract (a clouding of the central part of the lens).

The researchers also observed a dose-response relationship: Compared with low intakes, the risk for nuclear cataract went down as consumption went up. Specifically, for every 300 micrograms (1/3 of a milligram) of additional Lutein intake daily, the risk of nuclear cataract declined by 3%.

The finding is important because intake of Lutein / zeaxanthin is estimated to be 2 milligrams daily in the US, while about 6 milligrams a day has been linked to cataract risk reduction.

The meta-analysis findings echo the results of the Age-Related Eye Disease Study 2 (AREDS2). In AREDS2, participants with the poorest intake of dietary Lutein and zeaxanthin were 32% less likely to progress to a level of cataract requiring surgery. A 36% reduction in the development of any severe cataract was seen in AREDS2 as well.

While AREDS2 didn’t look at different types of cataract, the meta-analysis did. The researchers found that the risk for other types of cataract – cortical and posterior sub-capsular (cataracts on the edge of or at the back of the lens) were 15% and 23% lower in people who ate higher levels of Lutein and zeaxanthin, but a clear-cut dose-response was not seen for these cataract types.

Carotenoids & Omega-3 in Early AMD

A recent article2 by Tufts University researchers provided an overview of Lutein and zeaxanthin in early AMD. While calling for more research, the authors conclude that Lutein and zeaxanthin appear to diminish the development or progression of early AMD. The results of a new study bolster the article’s conclusion.

In this trial, researchers measured the density of macular pigment in people with early AMD who received either Lutein (12 mg), zeaxanthin (0.6 mg) and the omega-3 fat DHA (280 mg) daily or a placebo.

Early AMD is diagnosed by the presence of yellow-white spots called drusen in the macula. About 14% of people with the early stage of this disease will go on to develop late AMD over time.

Lutein and zeaxanthin are protective pigments concentrated in the macula. DHA was included with the carotenoids because it’s thought to increase the transport of Lutein and zeaxanthin to the retina, where it’s also involved in retinal function.

One year later, the patients getting the carotenoid and omega-3 combination had a significant increase in macular pigment density compared to the placebo-treated group. Some evidence suggests that increasing macular pigment density is related to the risk of developing AMD.

References

1. Le Ma et al. A dose–response meta-analysis of dietary lutein and zeaxanthin intake in relation to risk of age-related cataract. Graefes Arch Clin Exp Ophthalmol Oct, 2013. [Epub ahead of print].
2. Taney LS et al. Lutein and zeaxanthin in early AMD. Retinal Physician, Sept, 2013.
3. Garcia-Layana A et al. Effects of Lutein and Docosahexaenoic Acid Supplementation on Macular Pigment Optical Density in a Randomized Controlled Trial. Nutrients 5:543-51, 2013.

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In the News: Fighting Depression, Multivitamins and Breast Cancer

Depression is a Serious, Worldwide Problem

We have all experienced the everyday mood fluctuations and occasional blues that life can bring. But did you know that about 1 in 6 of us may also experience an episode of real depression during our lifetime? Depression – characterized by overwhelming sadness and hopelessness – affects more than 350 million people worldwide, and is responsible for a good portion of the global burden of disease according to the World Health Organization.

While antidepressant drugs are usually the first line of defense for depression, they don’t work adequately for more than half of patients. Further, many people would like to work with their health care professional to explore additional, non-drug treatment options for depression. Here are two new studies that illuminate some supplementary tools that may help in dealing with this disorder.

Omega-3s Linked to Lower Risk of Depression

Led by a National Institutes of Aging researcher, an investigative team examined whether there was an association between omega-3 intakes and symptoms of depression in over 1,700 U.S. adults using a 20-item depression rating scale (CES-D). Elevated depressive symptoms were seen in about 26% of women and 18% of men.

In this study (1), the highest intakes of omega-3s were associated with a significant 49% reduction in risk of elevated depressive symptoms for women. Evidence that depressive symptoms are inversely related to omega-3 fatty acids is growing, and the results of this study support a protective effect of the omega-3s against these symptoms, at least in women.

More Tools to Help Fight Depression

Results from a new study (2) conducted in the U.K. suggest that counseling and acupuncture hold significant promise in treating depression. This randomized trial is the first to rigorously assess the impact of acupuncture and counseling for patients who continue to experience depression in a primary care setting.

The researchers recruited 755 patients who had seen their primary care doctor for depression in the last 5 years, and who scored moderate-to-severe on a depression rating scale (BDI-II). The participants were randomly assigned to receive up to 12 weekly sessions of acupuncture plus usual care, 12 weekly sessions of counseling plus usual care, or usual care alone.

 ‘Usual care’, which included antidepressants, was available according to need and monitored in all three groups. Most of the patients had experienced recurring bouts of depression, with 76% having had 4 or more episodes.

Compared to usual care alone, those in the counseling and acupuncture groups had significantly improved scores at 3 and 6 months. For those who face recurring depression, both of these interventions alongside usual care may help them cope better.

Multis & Better Survival of Breast Cancer

Women who were diagnosed with invasive breast cancer during their participation in the Women’s Health Initiative (WHI) trial were the focus of a new analysis3.
Of the 7,700+ women who developed the disease (among the 161,608 postmenopausal women in the WHI), about 38% were taking multivitamin and mineral supplements. The vast majority of them reported using multis before their diagnosis.

The researchers found that the risk of dying from invasive breast cancer was 30% lower among those who used multis vs non-users. The association was strong, and was seen even after accounting for other factors that could have affected the outcome. While the findings require confirmation, they suggest that multi supplements may help older women better survive this disease.

References

1. Beydoun MA, et al. Omega-3 Fatty Acid Intakes Are Inversely Related to Elevated Depressive Symptoms among United States Women. J Nutr Sep 4, 2013 [Epub ahead of print].
2. MacPherson H, et al. Acupuncture and counseling for depression in primary care: A randomized controlled trial. PLoS Med 10:e1001518, Sept, 2013.
3. Wassertheil-Smoller S, et al. Multivitamin and mineral use and breast cancer mortality in older women with invasive breast cancer in the women's health initiative. Breast Cancer Res Treat Oct 9, 2013 [Epub ahead of print].

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In theNews: Anthocyanin-Containing Blueberries Reign Supreme

Good Reasons to Put ‘Purple’ on Your Plate

You’ve heard it before: eat more vegetables and fruit everyday, especially blueberries. It’s true that this tiny fruit can support health in big ways. Regular consumption of blueberries has been linked to a lower risk of heart disease and some cancers, and to better cognitive function as we age.

A new study confirms the importance of these berries (along with anthocyanin-containing fruits and a few others). Several other studies shed more light on one way they might be working to help keep blood vessels and the circulatory system functioning smoothly.

Certain Fruits Help Ward-Off Type 2 Diabetes, But Hold the Juice

Investigators have found that when it comes to fruit consumption and the risk of Type 2 diabetes, eating a greater variety rather than eating more is key (1). But are some fruits better than others at lowering that risk?

Harvard School of Public Health researchers set out to answer this question by looking at dietary data from more than 185,000 people, and following them over a 12-year period to see who developed Type 2.

After adjusting for other factors that can affect the chance of acquiring Type 2, they found that consuming blueberries, grapes, apples and grapefruit was associated with a significant reduction in risk, while other commonly eaten fruits such as oranges and peaches didn’t seem to have much of an impact.

Blueberries – which topped the risk-lowering list – resulted in a 26% risk reduction for those consuming 5 servings weekly.

One of the important findings of this study – the first to look at the effects of individual fruits on Type 2 risk – is that it’s best to skip the juice and go for the whole fruit instead. Greater consumption of fruit juices was associated with higher risk. People who consumed one or more servings of fruit juice daily increased their risk of developing Type 2 by as much as 21%.

Anthocyanins Help Keep Vessels Flexible

Epidemiologic studies suggest that increased consumption of anthocyanins (a type of flavonoid found in blueberries, bilberries and grapes) lowers the risk of cardiovascular disease, the most common cause of death among men and women. But how might these flavonoids be protective?

European researchers conducted two randomized, controlled trials, and report that anthocyanins may improve circulatory function in healthy men (2). The German and British collaborators investigated the effect of blueberry flavonoids on the function of the cells lining blood vessels, called the endothelium.

In the first study, they assessed the effects of various doses of anthocyanins on flow-mediated dilation, which is a way to measure the elasticity of blood vessels. As we age, blood vessels tend to lose their elasticity – a literal "hardening of the arteries" that is often a prelude to high blood pressure and cardiovascular disease.

The effective doses of anthocyanins they identified were equivalent to the amounts provided in about 3 ½ to 8 1/2 ounces of blueberries – a fairly easy amount to achieve. Flow mediated dilation increased after only an hour, and again at 6 hours.

The second study revealed that dose matters. The response in flow-mediated dilation improved with increasing dose, but not beyond the level of anthocyanins in 8 ½ ounces. These results suggest that regular consumption of anthocyanin-rich fruits can help maintain flexible vessels and healthy circulation.

References

1. Muraki I et al. Fruit consumption and risk of type 2 diabetes. Br Med J, Aug 28, 2013. [Epub ahead of print].
2. Rodriguez-Mateos A et al. Intake and time dependence of blueberry flavonoid-induced improvements in vascular function: A randomized, controlled, double-blind, crossover intervention study with mechanistic insights into biological activity. Am J Clin Nutr, Sept 4, 2013 [Epub ahead of print].

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In the News: Omega-3s & Stress, Yogurt & the Brain

Omega-3s May Help Blunt the Effects of Stress

Stress is a normal part of life. But scientists have long known that prolonged, unmanaged stress can negatively affect one’s health. There’s a well-documented link, for example, between mental stress and heart disease, high blood pressure, chest pains or irregular heart beats.

Evidence gained over the years also indicates that omega-3 fatty acids found in fish oil help protect against cardiovascular disease, yet the underlying protective mechanisms are still not fully clear.

Could there be a connection between mental stress and omega-3s when it comes to heart heath?

Results of a new NIH-funded study (1) suggest that there is, and that these fatty acids can blunt the detrimental effects of mental stress on the cardiovascular system.

In the study, participants underwent a mental stress protocol before and after 8 weeks of taking either a placebo or fish oil supplement daily (providing 1.6 grams of EPA and 1.1 grams of DHA). The stress protocol consisted of participants doing a mental arithmetic drill as fast as they could for 5 minutes.

The fish oil supplements significantly lessened the stress-provoked increases in heart rate and muscle activity compared to placebo.

In short, the study provides new evidence that fish oil reduces the way the heart beats in reaction to mental stress, and could be one way in which the omega-3s benefit cardiovascular health.

Can We Count Yogurt as a “Brain Food”?

In keeping with the topic of the mind-body connection, another unique study2 conducted at UCLA is the first to show an interaction between probiotics (friendly bacteria) and the brain in people.

We usually associate probiotics with digestive health, but the new research provides pretty compelling evidence that probiotics can also affect brain activity.

In this study (2), women ate either a probiotic-rich yogurt, or an unfermented yogurt without probiotics twice daily for a month.

The women then underwent an MRI before and after completing an emotion-recognition task. The task entailed viewing a series of pictures of people with angry or scared faces and matching them to other faces showing the same emotion.

The MRI provided images of the brain at rest and during the reaction to the emotion-matching task.

Changes in brain activity were clearly seen only in the probiotic-consuming group.

The “at rest” images showed greater connectivity between the midbrain and the thinking associated areas of the brain’s cortex. The probiotic group also showed less brain activity during the task, suggesting that they were better able to process emotion and sensation than the placebo group.

Although they don’t yet know the signaling pathways involved, the researchers do know that signals are sent from the intestine to the brain, and that friendly bacteria living in the gut can affect those signals.

Scientists now need to figure out how the signals are sent, and how their findings can best be used to benefit people. Probiotics could, for example, help those with abnormal responses to pain and stress related to microflora imbalance.

In the meantime, there are lots of good reasons to support a healthy microflora. Probiotic rich foods include yogurt, milk with acidophilus, fermented foods like kefir, miso, sauerkraut, kimchi and soft cheeses like Gouda and cottage cheese. You can also eat sources of prebiotics (foods that feed friendly bacteria) such as the soluble fibers in fruits, vegetables (jicama, garlic and onions particularly) and whole grains. Pro-and pre-biotic supplements are helpful as well.

References

1. Carter JR et al. Fish oil and neurovascular reactivity to mental stress in humans. Am J Physiol Regul Comp Physiol 304:R523-30, 2013.
2. Tillisch K et al. Consumption of fermented milk product with probiotic modulates brain activity. Gastroenterol 144:1394-1401, 2013.

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Supplement Shown to Benefit Dry Eye, Relieve Symptoms

Dry Eye Is a Growing Public Health Problem

An estimated 20-30 million Americans are affected by dry eye and that number is expected to rise as the US population ages. Dry eye is associated with a number of risk factors that can potentially impact many people such as aging, menopause, computer use, contact lens wear, LASIK, smoking, exposure to air pollution, dry environments, and diabetes mellitus. So it’s no surprise that dry eye is the one of the most common reasons that people visit their eye doctor.

Diagnosis and Treatment is Important

Treating chronic dry eye is important, as it can progress and lead to impaired vision and reduced quality of life. The symptoms of redness, itching, foreign body sensation and discomfort – as well as signs of surface damage in the cornea (the eye’s outer surface) and conjunctiva (the membrane covering the outer surface and inside eyelids) – can all have a detrimental effect on visual performance.

Although treatments such as artificial tears, anti-inflammatory drops, topical corticosteroids and punctal plugs can alleviate symptoms, there can be downsides to each. Artificial tears provide only short-term relief, for example, and topical corticosteroids may have ocular side effects.

Study Backs Fatty Acids, Antioxidants for Dry Eye

Because of these issues, researchers are constantly seeking new ways to treat and manage this condition. The omega-6 fatty acid GLA complemented by the omega-3s EPA and DHA, have shown promise in addressing signs and symptoms of dry eye in some studies. Now, researchers report that a unique blend of fatty acids, antioxidants and nutrient co-factors can meaningfully improve moderate to severe dry eye.

Conducted at Baylor College of Medicine and Virginia Eye Consultants, this randomized, placebo-controlled, double-masked trial examined the effects of a specialized supplement (HydroEye®, ScienceBased Health) on symptoms, signs and other measures in 38 post-menopausal women with moderate to severe dry eye1. Study participants were randomly assigned to receive the nutritional supplement or a placebo (2 softgels twice daily), and were evaluated over a 6-month period.

The results show that women in the supplement group had significant improvement in dry eye irritation symptoms, a smoother corneal surface and lower levels of inflammation than placebo-takers.

Symptoms: Symptoms were assessed using the ocular surface disease index (OSDI), a validated questionnaire that evaluates severity of eye discomfort. The OSDI score began to improve early on with supplementation, and progressively improved throughout the study period. The Improvement in scores reached significance by 3 months, and symptoms were significantly improved over placebo at 6 months.

Inflammation: Inflammation is a hallmark of dry eye. It was assessed in this study by two inflammatory biomarkers (HLA-DR and CD11c). Inflammation was held at bay in the supplement group with no further progression, while it actually worsened significantly in placebo-takers. Inflammation levels were significantly lower in the supplement vs. placebo groups at the study’s end.

Corneal Smoothness: Corneal topography is an imaging technique for mapping the surface curvature of the cornea. Since the cornea is normally responsible for some 70% of the eye's focusing power, its topography is important in determining quality of vision and corneal health. Measurements called topographic corneal regularity indexes were assessed in study participants as measures of corneal smoothness. These indexes have been reported to increase in dry eye. After 6 months, the supplement group maintained corneal smoothness, while the corneal surface became more irregular in placebo-takers.

According to investigator Stephen Pflugfelder, MD, “HydroEye clearly had a positive impact on these patients with moderate to severe dry eye. While this trial studied post-menopausal women, we think the benefits of HydroEye should apply to other populations suffering from dry eye since inflammation is believed to be a common thread in dry eye”.

To learn more about the study, visit: www.sbh.com/HydroEyeTrial.

References

1. Sheppard JD, et al. Long-term supplementation with n-6 and n-3 PUFAs improves moderate-to-severe Keratoconjunctivitis Sicca: A randomized double-blind clinical trial. Cornea 0:1–8, ePub ahead of print July, 2013.

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In the News: Magnesium & Heart Disease; Omega-3 & Skin Health; B-vitamins & AMD

Magnesium Reduces Risk of Heart Disease

Magnesium helps maintain muscle and nerve function, keeps heart rhythm steady, supports the immune system, and helps keep bones strong. It also helps regulate blood sugar levels, promotes normal blood pressure, and is involved in energy metabolism.

Researchers have long been interested in the role of magnesium in preventing and managing disorders such as diabetes, hypertension and cardiovascular disease (CVD). A new review of studies from Harvard’s School of Public Health bolsters the support for magnesium’s role in reducing the risk of CVD. 

The review (1), which included data for over 313,000 people from 16 studies, found that the risk of CVD fell by 30% (for every 0.2 mmol/L increase in circulating magnesium levels). Dietary intake of magnesium (per 200 mg/day increment) was associated with a 22% lower risk of ischemic heart disease.

The recommended daily intake for magnesium is 320 mg for women and 420 mg for men – amounts that many adult Americans fail to meet according to government surveys. To get more of this important mineral, eat a wide variety of leafy green veggies, beans, nuts, whole grains, and fish.

Can Omega-3 Fats Help Protect the Skin?

A preliminary, but promising study suggests that omega-3 fatty acids may have a role in helping to keep skin healthy.

Exposure to UV radiation in sunlight suppresses the skin’s immune system, specifically cell-mediated immunity. This suppression of immune activity can affect the body’s ability to fight skin cancer and possibly infections. 

The omega-3s have been shown to protect against UV-caused immune suppression in mice, but their impact in humans isn’t known.  This led Investigators at the University of Manchester in England to clinically test whether a regular dose of fish oil can boost skin immunity to sunlight (2). 

After 3 months of taking 4 grams of EPA/DHA or placebo supplements, the 79 study participants were exposed to the equivalent of 8, 15 or 30 minutes of summer midday sun using a special light machine. Immune suppression was 50% lower in people receiving EPA/DHA compared to those in the placebo group for the 8 and 15 minutes sun exposure. The authors caution that their results need to be verified in larger trials, and that taking omega-3s should add to the protection against sun damage afforded by sunscreen and protective clothing, but would not replace these measures. They also emphasize that the beneficial changes, though small, suggest that a continuous low level of protection from the omega-3s could provide meaningful skin protection over a lifetime. Additionally, lower doses of omega-3 may be needed when they’re taken for longer periods of time (since checking with your doctor is advised for doses over 3 grams).

B-vitamin Intake Linked to Lower AMD

A clinical trial published in 2009 reported that daily supplementation over time with high dose vitamin B6 and B12, and folic acid could reduce the risk of age-related macular degeneration (AMD) in women.

Results of a new study (3) lend credence to these clinical findings, and suggest that more moderate intakes of folic acid and supplemental B12 may lower AMD risk.

Participants in the Blue Mountains Eye Study were followed for 10 years. Those with elevated blood levels of damaging homocysteine, low levels of folic acid, or vitamin B12 deficiency, were at significantly greater risk of developing early or late stage AMD.

Participants who reported taking B12 supplements were 47% less likely to develop AMD. That’s important because B12 deficiency is fairly common in older people, and supplemental B12 is more bioavailable than dietary sources of this vitamin.

References

1. Del Gobbo LC, et al. Circulating and dietary magnesium and risk of cardiovascular disease: a systematic review and meta-analysis of prospective studies. Am J Clin Nutr 98:160-173, 2013.    
2. Pilkington SM, et al. Randomized controlled trial of oral omega-3 PUFA in solar-simulated radiation-induced suppression of human cutaneous immune responses. Am J Clin Nutr 97:646-52, 2013. 
3. Gopinath B, et al. Homocysteine, folate, vitamin B-12, and 10-y incidence of age-related macular degeneration. Am J Clin Nutr 98:129-135, 2013.

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Understanding the Results of AREDS2

2nd Age-Related Eye Disease Study (AREDS2)

Results of the second AREDS trial (AREDS2) were released in early May (1). The bottom line? Consider taking the original AREDS formula with beta-carotene replaced by lutein and zeaxanthin if you have at least intermediate AMD.

AREDS2 had a complex study design. All participants were randomly assigned to one of four groups: placebo (the control group), lutein (10 mg) plus zeaxanthin (2 mg), omega-3 fatty acids (1000 mg), or both.

Everyone in the trial was also offered the original AREDS formula (vitamins C and E, beta-carotene, zinc and copper). Many opted to take the original supplement, while others agreed to take modified formulas with reduced zinc and/or no beta-carotene.

The main goal of the study was to see whether adding lutein + zeaxanthin or omega-3 fatty acids to an AREDS formula would be more effective in reducing the risk to advanced AMD than taking the AREDS formula alone.

Compared to taking only the AREDS formula, neither the added omega-3 nor lutein/zeaxanthin met the additional 25% decrease in risk that was required to show effectiveness.

However, there were other important sub-group findings – not widely covered by the media – that may well have influenced the main outcome in the lutein + zeaxanthin groups.

Lutein and Zeaxanthin May Be of Benefit

High dose beta-carotene appeared to interfere with the absorption of lutein/zeaxanthin, as evidenced by lower blood levels of lutein/zeaxanthin in those getting the original formula with beta-carotene. In fact, when beta-carotene was removed from the formula, the researchers did find evidence that lutein + zeaxanthin can slow progression to advanced AMD.

Those taking lutein + zeaxanthin and no beta-carotene had an 18% lower risk compared to people getting beta-carotene (and no lutein + zeaxanthin).

In addition, the lutein/zeaxanthin supplements made a real difference for those with the lowest dietary intake of these carotenoids. A 26% reduction in risk of progression was seen for those with the poorest dietary intake who received lutein and zeaxanthin.

The investigators noted that overall, AREDS2 participants tended to have diets richer in lutein and zeaxanthin than the general population. That’s important because a substantial portion of Americans typically consume less than 1-2 mg of these carotenoids daily.

According to the investigators, it’s possible that a greater benefit would have been seen for lutein/zeaxanthin if the diets of the AREDS2 patients had been more representative of the general population.

What About Zinc and Beta Carotene?

Another goal of the study was to assess the effects of lowering the zinc dose from the original 80 mg to 25 mg, and eliminating beta-carotene. Neither of these changes made a significant difference in the effectiveness of the formula.

The higher dose of zinc, however, showed a favorable trend toward better protection, and there was no difference observed between the two zinc doses in terms of safety. Therefore the research group recommends the higher dose of zinc, while noting that the zinc results were not definitive.

AREDS Benefits Are Long-Lasting

In a recently published follow-up study of the original AREDS trial, researchers found that the effects of taking the AREDS supplement are long- lasting (2).

After the original trial ended, participants were followed for another 5 years. At the end of that period, those who had taken the AREDS formula were 25-30% less likely to develop advanced AMD.

Considering the findings of this follow-up study and of AREDS2, there’s every reason to be confident that the AREDS formula (with lutein and zeaxanthin replacing beta carotene) will provide at least similar protection against the progression of AMD.

Cataract

AREDS2 also asked whether adding lutein/zeaxanthin or omega-3s to the original AREDS formula would impact the need for cataract surgery (3). No statistically significant overall effect was seen.

However, again, participants with the poorest intake of dietary lutein and zeaxanthin did benefit by getting supplements of these carotenoids. This group was 32% less likely to progress to a level of cataract requiring cataract surgery. A 36% reduction in the development of any severe cataract was seen as well.

Take Home Message?

While AREDS2 was a complicated trial, the overall message is simple: If you have at least intermediate AMD, discuss taking the AREDS formula (containing lutein + zeaxanthin) with your doctor. This is especially important if you have AMD or cataract and don’t include enough lutein and zeaxanthin-rich leafy greens such as kale, collards and spinach in your diet.

Omega-3s: More Research Needed

AREDS2 found that the omega-3s taken with the AREDS formula did not provide further benefit for those with intermediate to advanced AMD. However, that does not rule out a possible benefit for people with early stage AMD or who are at risk for the disease.

One population health study (4) with over 38,000 women who were free of AMD at the study’s start, reports that regular intake of the omega-3s over a 10-year period significantly lowered the risk of developing AMD. While these findings suggest that the omega-3s could be helpful in primary prevention of AMD, more research is needed to understand what role the omega-3s may play in maintaining visual health.

References

1. The AREDS2 Research Group. Lutein + zeaxanthin and omega-3 fatty acids for age-related macular degeneration. JAMA Ophthalmol Epub ahead of print, May 5, 2013.
2. Chew EY et al. Long-term effects of vitamins C and E, B-carotene, and zinc on age-related macular degeneration Ophthalmology Epub ahead of print, April 11, 2013.
3. The AREDS2 Research Group.
4. Christen WG, et al. Dietary omega-3 fatty acid and fish intake and incident Age-Related Macular Degeneration in women. Arch Ophthalmol 129:921-29, 2011.

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In the News: For Brain Function: More DHA, Less Processed Carbs

Importance of the Omega-3s in the Brain

Both of the omega-3 long-chain fatty acids EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid) are found in brain tissue, but DHA is the most abundant. DHA comprises about 40% of the polyunsaturated fatty acids (PUFAS) in the brain, and 60% of PUFAS in the eye’s retina.

The level of DHA present in brain cell membranes is affected by the type and amount of fatty acids in our diet. DHA brain levels are also affected by our life stage. DHA is crucial in early life for proper brain and visual development. Studies have shown, for example, that pregnant women who consume higher amounts of omega-3s transfer more DHA to their babies.

While DHA levels increase during infancy and early childhood, those levels decline as we grow older. This has led to ongoing research examining whether higher omega-3 intake can improve memory and learning in healthy, older adults with mild memory complaints.

But if DHA is needed to build cognitive capacity in children and, quite possibly, to support mental ability in older people, could it be of any benefit to younger healthy adults? While some researchers have scoffed at the idea of potential DHA benefits in this “in-between age group”, a new study (1) suggests that DHA supplementation can be helpful in younger people – at least those whose diet is low in this omega-3.

Memory and Reaction Time Improved

For the study, British researchers recruited 176 healthy young adults aged 18-45 years. The participants were assigned to take either placebo or DHA supplements daily for 6 months, and were given a battery of computerized cognitive tests at the beginning and end of the trial.

Both episodic memory and working memory improved for the DHA group compared to placebo takers. However the benefits were more pronounced in women, for episodic memory – the memory of events (times, places, associated emotions and other contextual knowledge). Men, on the other hand, benefited more for reaction times of working memory, an area of short-term memory involved in high-speed processing. Reaction times for men increased by 20% following DHA supplementation.

High Carb Intake Linked to Cognitive Risk

If eating more omega-3 rich fish is a good idea for supporting brain function, consuming fewer processed carbs such as processed grains and sugar is also a good strategy according to new study results (2) from the Mayo Clinic.

The investigators obtained dietary information for over 1,200 people 70-89 years of age, and evaluated their cognitive function. Only the 940 participants who showed no signs of cognitive impairment were tracked. Of those, 200 were starting to show mild problems with language, thinking, memory and judgment about four years later.

They found a significantly higher risk of developing mild cognitive impairment for those who ate the most carbs relative to fat and protein. A diet heavy in sugar also raised the risk substantially.

The researchers emphasize the importance of eating a diet with balanced amount of fats, proteins and carbs. A diet overly heavy in easily digested carbs and sugars might contribute to cognitive risk by impacting glucose (blood sugar) and insulin metabolism. Cognitive deficits and decline have been seen in older people with poor glucose tolerance, and insulin insensitivity and diabetes are risk factors for brain function decline and dementia.

References

1. Stonehouse W et al. DHA supplementation improved both memory and reaction time in healthy young adults: a randomized controlled trial. Am J Clin Nutr [ePub ahead of print March 20, 2013].
2. Roberts RO et al. Relative intake of macronutrients impacts risk of mild cognitive impairment or dementia. J Alzheimers Dis ;32:329-39, 2012.

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Turmeric & Arteries; Lutein in early AMD; Calcium & CVD

Curry Spice May Boost Blood Vessel Health

Curcumin is the yellow-orange pigment found in turmeric, the spice used in Indian curry dishes. Researchers have been interested in curcumin for some time, and the compound has shown some preliminary promise in addressing colon polyps and reducing inflammation in arthritis.

The new study (1) looked at the effects of curcumin on the ability of blood vessels to dilate when needed. A key step in the development of atherosclerosis or “hardening” of the arteries occurs when the lining of the vessels (called the endothelium) does not function properly to help regulate blood flow.

Researchers assigned postmenopausal women to one of three groups: one received 25 mg of curcumin daily, another undertook moderate aerobic exercise training, and a third group served as a control.

After 2 months, both the curcumin and exercise groups had significant – and equal – improvements in flow-mediated dilation (FMD). FMD is a test of endothelial function and the ability of vessels to dilate when blood flow increases. In contrast, no improvements in FMD were observed in the control group. Though the study was small, the results indicate that this spice has good heart-health potential.

Lutein May Benefit Visual Acuity in Early AMD

Lutein and zeaxanthin are part of the eye’s macula, the functional center of the retina. The macula provides us with sharp central vision and it contains photoreceptors called cones that provide color vision. Lutein and zeaxanthin, known as macular pigment, play a critical role in protecting the macula from harmful blue light.

The density of macular pigment has been shown to decline with age, and having low macular pigment density is considered a risk factor for AMD. Lutein and zeaxanthin, in fact, are being tested in the 2nd Age-related Eye Disease Study (AREDS2), to see whether they can slow the progression of AMD in people who already have intermediate to advanced stages of the disease. While AREDS2 isn’t studying people with early signs of AMD, new research from the UK sheds some light on the effects of Lutein in early-stage AMD.

In this study (2), patients received either 10 mg of Lutein or a placebo for 12 months. Macular pigment density increased significantly in the Lutein group. Visual acuity, a measure of the sharpness of vision, was unchanged in the Lutein group as a whole, while it deteriorated in the placebo takers.

Further analysis showed that Lutein did improve visual acuity in those who had poor clarity of vision at the study’s start. The investigators suggest that Lutein supplementation may slow the progress of AMD in some patients in the early stages of the disease.

Can Too Much Calcium Cause Heart Disease?

Several studies have recently reported a link between high intake of calcium from diet and supplements and a higher risk of heart disease. The theory is that excess calcium can be deposited in arteries, making them stiff and leading to heart conditions and stroke. A newly published study (3), however, suggests that concern about calcium supplementation doesn’t seem to be warranted.

Investigators performed CT scans on participants in the Framingham Offspring Study four years after collecting information about their diet and supplement use. The CT scans found no association between even the highest calcium intake (from food and supplements combined) and coronary artery calcification.

Though these findings are reassuring, keep in mind that taking higher-than-recommended amounts of calcium offers no benefit. A new analysis (4) of the large Women’s Health Initiative found that 1,000 mg of calcium (+ 400 IU vitamin D) daily substantially lowered the risk of hip fracture in postmenopausal women with no risk of cardiovascular harm.

References

1. Akazawa N et al. Curcumin ingestion and exercise training improve vascular endothelial function in postmenopausal women. Nutr Res 32:795-9, 2012.
2. Murray IJ et al. Lutein supplementation over a one-year period in early AMD might have a mild beneficial effect on visual acuity: the CLEAR study. Invest Ophthalmol Vis Sci 11:1781-8, 2013.
3. Samelson EJ et al. Calcium intake is not associated with increased coronary artery calcification: the Framingham Study. Am J Clin Nutr 96:1274-80, 2012.
4. Prentice RL et al. Health risks and benefits from calcium and vitamin D supplementation. Osteo Inter 24:567-80, 2013.

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The Mediterranean Diet, Green Tea, & Vitamin D

Med Diet Offers Powerful Heart Protection

A widely covered study published in the New England Journal of Medicine offers the most compelling evidence yet that the Mediterranean style of eating is the way to go for better heart health (1).

The Med-style diet had already been shown to help protect people who have cardiovascular disease (CVD). The new study confirms that the diet also protects those at risk of developing it. The odds of having a heart attack, stroke, or dying from CVD fell by a meaningful 30% in those adopting the diet.

The study, which followed over 7,400 women and men, was stopped ahead of time when a clear-cut health disadvantage was seen for the control group on a low fat diet.

Moving Toward the Med Diet Isn’t Hard

None of the study participants were asked to curb calories, and the two Med diet groups – one that ate nuts daily and the other that consumed extra olive oil – had little trouble sticking with the diet. A diet that doesn’t require calorie restriction and that’s easy to follow is appealing.

The Med diet is rich in fresh fruits and veggies, seafood, whole-grains and mono-unsaturated fats (the type in olive oil). All groups in this study were able to cut back on meats, sweets, dairy and alcohol, but the main difference between interventions was that the Med diet group ate fewer carbs and more fats (mostly from olive oil), fruit, beans and nuts.

Can Green Tea Lower Breast Cancer Risk?

Although a number of population health studies support a link between green tea intake and the risk of breast cancer, there is a need for more randomized clinical trials to help clarify whether green tea has a role in preventing this cancer.

A new report (2) from the National Cancer Institute (NCI) sheds some light on how green tea might influence breast cancer risk. NCI researchers followed nearly

The researchers found that daily consumption of green tea was associated with lower levels of estrogen metabolites in the urine of postmenopausal women.

The polyphenols in green tea, according to the authors, may modify breast cancer risk by interacting with enzymes that metabolize estrogen.

While we await the results of further investigations, experts have concluded that drinking 3-5 cups of this tea daily is safe and healthful.

Vitamin D May Influence Risk of Dying

Vitamin D plays a role in many processes within the body including regulating inflammation, the immune system and the secretion of insulin. These wide-ranging effects have led researchers to explore the relationship of vitamin D to mortality.

In the most recent exploration3, researchers from Vanderbilt University and Meharry Medical College report that people with the highest blood levels of vitamin D were less likely to die earlier than those with the lowest blood levels.

Better vitamin D blood values were most protective against early death from circulatory disease, and lower risk for overall mortality was seen for values that were at least 35-40 ng/mL. Although poor vitamin D levels are most common among African Americans, the study’s findings held true for other ethnic groups as well.

References

1. Estruch R et al. Primary prevention of cardiovascular disease with a Mediterranean diet. NEJM [Epub ahead of print Feb 25, 2013]
2. Fuhrman BJ et al. Green tea intake is association with urinary estrogen profiles in Japanese-American women. Nutr J 12:25 [Epub ahead of print Feb 15, 2013].
3. Signorello L et al. A prospective study of serum 25-hydroxyvitamin D levels and mortality among African Americans and non-African Americans. Am J Epidemiol 177:171-79, 2013.

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Zinc & Eye Health, Berries & Tomatoes for the Heart

Zinc Has Many Functions in the Body

Zinc is found in all parts of the body, and plays a vital role in many aspects of health. Getting an adequate amount of Zinc is important for children to grow and develop, for example, and it’s needed for nerves to function properly. Among all the vitamins and minerals, Zinc shows the strongest effect on our all-important immune system.

As the results of the 1st Age-related Eye Disease Study (AREDS) revealed in 2001, Zinc is also very important in reducing the risk that age-related macular degeneration (AMD) will progress in people with the disease. Zinc is believed to play a role in the development of AMD for several reasons. First, Zinc is highly concentrated in the part of the eye’s retina affected by AMD. Additionally, both the level of Zinc and the activity of key Zinc-requiring enzymes in the retina have been shown to decline with age.

Zinc’s Role in Eye Health Has Ancient Origins

While the benefits of Zinc to the eye’s retina came to the forefront with publication of the AREDS trial, it appears that the role of this mineral in ocular health is rooted in history.

Italian researchers recently analyzed Zinc supplement tablets that were uncovered in a 2000 year-old shipwreck off the coast of Tuscany (1). The supplements were found in the Pozzino, a ship that sank in the 2nd century B.C., and were preserved underwater in oxygen-free metal tins.

The research team believes that the supplements were used to treat eye problems, since the tablets are similar in shape and composition to those described in ancient texts discussing the medicinal use of Zinc. Some of these texts date back as far as 300 B.C.

As we await results of the AREDS 2 trial now in progress, these intriguing findings shed light on the continuity of Zinc use from ancient to modern times.

Higher Lycopene Intake May Reduce CVD Risk

A new study from Tufts and Boston University reports a link between intake of lycopene in the diet and the risk of developing cardiovascular disease (CVD) and coronary heart disease (CHD) (2).

lycopene is a carotenoid found in red and pink-colored fruits and vegetables. However, tomatoes and tomato-based products (e.g. ketchup and tomato sauce) are by far the most important dietary sources of this antioxidant.

The findings, which were based on data from the Framingham Offspring Study, showed that people consuming the most lycopene reduced their risk of developing CVD by 17%, and were 26% less likely to develop CHD.

The average intake of lycopene was 7.9 mg. among the women. One fresh tomato contains about 4 mg, and 1 cup of tomato sauce provides about 25 mg.

Berries May Support Women’s Heart Health

Women who eat three or more weekly servings of blueberries and strawberries could be helping their hearts according to a new study from Harvard (3).

The Harvard team looked at data from 93,600 women aged 25-42 who participated in the Nurses’ Health Study II. Eating the highest amounts of these two berries was associated with a 1/3 reduction in risk of heart attack. This observation held up even among women who ate a diet rich in other fruits and vegetables.

What is it about these berries that could protect against heart attacks? They’re a rich source of flavonoid substances, called anthocyanins, which have been linked to reduced blood vessel hardening and reductions in markers of inflammation – risk factors for heart disease.

References

1. Giachi G, et al. Ingredients of a 2000-year-old medicine revealed by chemical, mineralogical and botanical investigations. PNAS; ePub ahead of print Jan. 7, 2013.
2. Jacques PF, et al. Relationship of lycopene intake and consumption of tomato products to incident CVD. Br J Nutr EPub ahead of print Jan. 15, 2013
3. Cassidy A, et al. High anthocyanin intake is associated with a reduced risk of myocardial infarction in you and middle-aged women. Circulation 127:188-96, 2013.

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Antioxidant Nutrients, Early AMD, & Visual Function

What is Visual Function?

Vision is composed of many simultaneous functions. One function, called visual acuity, measures “sharpness” of vision, or how well we see details when they are presented with good contrast. This is measured by looking at a standard eye chart where you’re asked to read lines of black letters on a white background that get smaller from top to bottom. For example if you can see the smallest line that a person with normal acuity can read at a distance of 20 feet, you’re said to have 20/20 vision.

While visual acuity is the cornerstone of any eye exam, there are other important aspects of vision. Some of these include our ability to adapt to changing light conditions (light and dark adaptation), how well we deal with glare that can impair our vision (glare disability), and how well we see contrasting colors (chromatic contrast).

Macular Pigment and Visual Function

Macular pigment is the yellow spot found in the center of the eye’s retina known as the macula, and it acts like an internal pair of sunglasses. Made up of two antioxidant carotenoids that we get from our diet, lutein and zeaxanthin, the macular pigment plays a critical role in protecting the macula from harmful blue light,

The density of macular pigment is important. Low macular pigment density, for example, is considered a risk factor for age-related macular degeneration (AMD).  Results from a newly published study (1) suggest that macular pigment density can also have immediate effects on visual function.

Researchers from the University of Georgia measured blood levels of lutein and zeaxanthin as well as the density of macular pigment in 150 healthy young participants. They also performed tests to measure chromatic contrast, glare disability, and photo-stress recovery (the time it takes to recover vision after exposure to very intense light).

The research team will next explore whether giving the participants supplemental lutein and zeaxanthin (12 mg combined) or a placebo will improve macular pigment density and these measures of visual function over the course of a year.

Antioxidants and Early AMD

Nearly twelve years ago, The Age-related Eye Disease Study (AREDS) showed that high dose zinc with copper and antioxidants (vitamins C, E, beta-carotene) could slow the progression of AMD, but only in people with moderate to advanced stages of the disease.

Although the findings need to be confirmed in larger and longer clinical studies, a team of investigators from Ireland now reports that a combination of nutrients may also offer some benefit to people with early stage AMD (2).

Over 430 men and women aged 55 or older received either a placebo or a daily supplement containing lutein and zeaxanthin (12.6 mg), vitamin C (150 mg), vitamin E (15 IU), zinc (20 mg) and copper (.6 mg). 

While no significant difference in best-corrected visual acuity was seen between the two groups at the end of 1 year, some of the participants were followed for up to 3 years.

For participants followed for the 3-year period, those getting the supplement were found to read nearly 5 letters more on a standard eye chart than those in the placebo group. Also, those with higher blood levels of lutein had a slower disease progression as assessed by an AMD severity scale at years 1, 2 and 3.

References

1. Hammond BR et al. Glare disability, photostress recovery, and chromatic contrast: relation to macular pigment and serum lutein and zeaxathin. Invest Ophthalmol Vis Sci, ePub Dec. 4, 2012.
2. Beatty S et al. Secondary outcomes in a clinical trial of carotenoids with coantioxidants versus plaebo in early age-related macular degeneration. Ophthalmol, ePub Dec. 5, 2012.

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In the News: Focus on Flavonoids, Vitamin D & Diabetes

A Key Component of Fruits and Veggies

Naturally occurring plant pigments, flavonoids are one of the reasons fruits and vegetables – from blueberries to onions – are so healthful. Eating more flavonoid-rich foods or drinking flavonoid-laden beverages such as green tea and wine, has been linked to a lower risk of chronic diseases including heart disease and stroke.

Some flavonoids act by corralling cell-damaging free radicals, but others influence the way cells receive, send and process signals that help them respond to their environment. Though most flavonoids aren’t well absorbed, the small amounts that do get into the blood stream and tissues seem to have potent effects.

Last month’s Staying Healthy issue featured a study linking dietary flavonoid intake and prostate health. This issue highlights new research1 that illustrates the diverse health-promoting potential of these nutrients.

Cocoa Flavonoids May Boost Mental Function

Prior studies have associated flavonoid intake with a decreased risk for dementia in older individuals. To investigate further, a team of Italian investigators enrolled 90 older individuals with mild cognitive impairment for an 8-week study. Participants were randomly assigned to consume a daily beverage containing low (45 mg), medium (520 mg) or high levels (990 mg) of cocoa flavanols (one class of flavonoids). The team assessed mental function using well-known cognitive tests.

People in both the medium and high level flavonoid groups were faster at completing tests which measure visual attention and mental flexibility, and also had significantly higher scores in verbal fluency. The verbal fluency test consists of giving people 60 seconds to list as many things as possible in a category, such as naming all the fruits and vegetables they can think of.

Improvements in blood pressure and the body’s sensitivity to insulin were also seen in those drinking the medium and high-level beverages. According to the researchers, the enhanced ability of insulin to process blood sugar had the greatest influence on the changes in cognitive function observed.

This study used special high-flavanol beverages, providing much higher flavanols than found in standard hot cocoa mixes on the market. Look for brands that are high in flavanols and low in sugar. Also tea, beans, apricots, berries, apples and some dark chocolate (in moderation) can contribute to overall flavanol intake.

Vitamin D and Diabetic Risk of Heart Disease

People with diabetes have a higher risk of heart disease that comes from developing clogged arteries, or atherosclerosis. The results of a small but intriguing study2 suggest that low levels of vitamin D could be one factor involved in the process of forming artery-blocking plague.

Researchers looked at vitamin D levels in people with and without diabetes who were similar in age, gender and weight. They found that diabetic patients with low vitamin D (defined as less than 30 ng/ml) had certain white blood cells that were more likely to stick to cells in the wall of blood vessels. When they adhere to vessel walls, these white blood cells (called macrophages) can fill up with cholesterol – an important step in the process of plaque formation.

The investigators point out that it’s not yet known whether improving blood levels of vitamin D can actually decrease the risk of developing atherosclerosis in diabetes. However, future trials are being planned that will test this idea.

References

1. Desideri G, et al. Benefits in cognitive function, blood pressure, and insulin resistance through cocoa flavanol consumption in elderly subjects with mild cognitive im-pairment: the Cocoa, Cognition, and Aging (CoCoA) study. Hypertension 60:794-801, 2012.
2. Riek AE, et al. Vitamin D suppression of endoplasmic reticulum stress promotes an antiatherogenic monocyte /macrophage phenotype in type 2 diabetic patients. J Biol Chem 287:38482-94, 2012.

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In the News: “Multi” Use Cuts Cancer Risk; Flavonoids & Prostate Health

Daily “Multi” Reported to Reduce Cancer Risk

Consistent use of a daily multi-vitamin and mineral supplement can pay a healthy dividend for men according to a study (1) newly published in the Journal of the American Medical Association.

The Harvard investigators who conducted the study report an 8% decrease in total cancer occurrence. The reduction in total cancer rate was found to be 12% when they removed prostate cancer from the analysis (no effect on prostate cancer rate was seen). Regular multi use also lessened the risk of dying from cancer by 12%, though that figure was just shy of reaching statistical significance.

The study is unique in a number of ways. It’s the first and only large-scale placebo-controlled trial (the most rigorous type of study) to evaluate a multi-supplement in the prevention of cancer, with over 14,600 physicians 50 years or older participating. Secondly, the physicians were followed for a long time – 11 years on average, with up to 14 years of treatment for some of them.

The study’s findings are important both from a public health and an individual perspective. An 8% decrease in cancer risk may seem modest. But with more than 1.6 million new cancer cases diagnosed yearly in the US, this risk reduction translates into about 130,000 cancers prevented every year.

Along with healthy habits such as not smoking and eating a diet rich in fruits and vegetables, adding a daily multi supplement may well make a meaningful contribution to cancer prevention. As one researcher affiliated with the Fred Hutchinson Cancer Research Center points out, other than quitting smoking there’s no single measure one can take that’s been shown to reduce cancer risk by nearly 10%.

The physicians who took part in the trial were healthy, with good dietary and lifestyle habits. Over 2/3 of them exercised regularly and only 4% smoked (though 40% were former smokers). They were also diligent about taking the supplements over time.

Can consistently taking a good quality ‘multi’ also lower the risk for cancer in less healthy or younger people, women, and those or who aren’t health professionals? While this study can’t provide those answers, it’s reasonable to believe that the impact in the general population could be even greater.

The study also goes a long way in confirming that balanced multis are generally safe to take (adverse effects in the supplement group were minor, with supplement takers slightly more likely to have rashes than those taking the placebo).

Dietary Flavonoids Linked to Prostate Cancer

While multi-supplement use does not appear to reduce the risk of prostate cancer, eating foods rich in compounds known as flavonoids just might offer some hope.

A study (2) presented this month at an international conference on cancer prevention reports that men with the highest intake of total flavonoids had a 25% lower risk of aggressive prostate cancer than those consuming the least total flavonoids. In addition, the risk for aggressive prostate cancer was even lower in men younger than 65, and in current smokers with the highest levels of flavonoid intake. The study included 920 Afro-American and 977 Caucasian men who were newly diagnosed with prostate cancer.

They found that no one type of flavonoid appeared to be responsible for the protective effect. This suggests that it’s important to consume a variety of plant-based foods in the diet, rather than to focus on one specific type of flavonoid or flavonoid-rich foods. Top contributors to total flavonoid intake among the participants were citrus fruits and juices, tea, grapes, berries, onions and greens.

While further research will need to confirm the study’s findings, eating more flavonoid-rich foods is of benefit to overall health.

References

1. Gaziano JM, et al. Multivitamins in the prevention of cancer in men—The Physicians’ Health Study II randomized controlled trial. JAMA, Published online ahead of print October 17, 2012.

2. Steck S, et al. Increased Flavonoid Intake: Reduced Risk for Aggressive Prostate Cancer. 11th Annual AACR International Conference on Frontiers in Cancer Prevention Research, Anaheim, CA, Oct.16-19, 2012.

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Two for the Heart: Potassium & Berry Flavonoids

Potassium Prowess in Fighting Heart Disease

Potassium, sodium’s beneficial chemical cousin, can help bring down blood pressure and may reduce the risk of stroke according to several recent reviews.

In one review (1) of published studies, scientists calculated that if Americans could bring their potassium intakes up to recommended levels, cases of high blood pressure would dip by 10%. Right now, about 1 in 3 adults suffer from hypertension.

The authors of this study concluded that boosting potassium and slashing sodium intake is probably the most important dietary choice we can make (after weight loss) to combat cardiovascular disease.

In another review (2), Swedish researchers analyzed the findings of 10 prior prospective studies that included a total of more than 268,000 participants.

The investigators found that increased potassium intake was linked to a reduced risk of stroke, particularly ischemic stroke, which is the most common type. In fact, for every 1000 mg daily increase in potassium intake, the risk of stroke fell by 11%.

Most people aren’t deficient in potassium. But even moderately low levels of this mineral can contribute to salt sensitivity and high blood pressure, a risk factor for heart disease and stroke.

Unfortunately, most Americans aren’t getting enough potassium. A study published this month (3) which looked at the National Health and Nutrition Examination Survey, reports that the vast majority of US adults consume too much sodium and too little potassium.

Putting a “Potassium Plan” into Action

The simplest way to a better balance between these two minerals is to cut back on processed foods and choose more potassium-rich fruits and vegetables. The American Heart Association advises that the daily intake of sodium should be 1,500 mg or less, while the recommended potassium intake is at least 4,700 mg per day or more.

Curbing Inflammation, Hypertension with Berry Flavonoids

While you’re eating more fruits and veggies to pump up potassium intake, be sure to include berries (blue, black and red), grapes, and vegetables such as eggplant and red onion. That’s because these foods are good sources of red-blue antioxidant pigments called anthocyanins (a type of flavonoid).

Research suggests that anthocyanins can help dampen low-level chronic inflammation – a risk factor for atherosclerosis and thus heart attacks and strokes. In a new study (4) of 150 people with high cholesterol levels, those receiving 320 mg of anthocyanins for 6 months had a 22% reduction in a biomarker of inflammation (C-reactive protein). Placebo-takers had only a 2.5% reduction.

Analyzing data from about 1,900 women, the authors of a second study (5) report a link between higher intake of anthocyanins and a significantly lower blood pressure (both diastolic and systolic). Higher intakes were also associated with biomarkers of artery stiffness. Stiff, less elastic arteries are seen in atherosclerosis.

The authors note that the anthocyanin intakes associated with these heart-healthy benefits are equivalent to eating 1-2 portions of berries daily – a very achievable goal.

References

1. Houston MC and Harper KJ. Potassium, magnesium and calcium: their role in both the cause and treatment of hyper-tension. J Clin Hypertens 10 (7 Suppl 2):3-11, 2008.
2. Larsson SC et al. Dietary potassium intake and risk of stroke: a dose-response meta-analysis of prospective studies. Stroke 42:2746-50, 2011.
3. Cogswell ME et al. Sodium and potassium intakes among US adults: NHANES 2003-2008. Am J Clin Nutr. 96:647-57, 2012.
4. Zhu Y et al. Anti-inflammatory effect of purified dietary anthocyanin in adults with hypercholesterolemia: A randomized controlled trial. Nutr Metabol Cardio Dis. Epub Aug, 2012.
5. Jennings A et al. Higher anthocyanin intake is association with lower arterial stiffness and central blood pressure in women. Am J Clin Nutr, 96:781-8, 2012.

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Antioxidants & Cancer; Supporting Mental Function

Antioxidant Trio & Pancreatic Cancer Risk

Awareness of pancreatic cancer rose last month with the news that astronaut Sally Ride, the first U.S. woman in space, lost her battle with this disease. Pancreatic cancer, which also claimed the life of Apple co-founder Steve Jobs last year, is relatively rare. The number of people affected by pancreatic cancer yearly is fairly low: a little more than 250,000 globally. It has, however, the worst survival rate of any cancer.

While genes, smoking and type-2 diabetes are all major risk factors for pancreatic cancer, it’s thought that diet, too, could play a role. In support of that idea are new findings that increasing dietary intake of certain antioxidants may help cut the risk of developing this cancer by up to two-thirds (1).

Findings from the ‘EPIC’ Study

U.K researchers tracked the health of nearly 24,000 people who took part in the European Prospective Investigation of Cancer (the EPIC study). Participants completed comprehensive food diaries that detailed the types and amounts of every food they ate, including the methods used to prepare it. The researchers analyzed the nutrient intakes of those who developed pancreatic cancer within 10 years of entering the study, and compared that with the intakes of about 4,000 healthy people to see if there were any differences.

They found that those with the highest intake of vitamins C, E and selenium were 67% less likely to develop the disease than those consuming the least. If this association holds true, 1 in 12 of these cancers might be prevented, according to the researchers.

Tips for Staying Mentally Sharp

There are many factors that can affect our ability to concentrate and be mentally sharp on any given day. Examples include: what we eat, whether we are physically active, how we manage stress, and whether or not we’ve had a good night’s sleep.

Drinking caffeinated coffee is probably the most popular way to gain a temporary mental boost. (Research also suggests that this morning routine may have even more enduring effects on mental well-being and health. Moderate coffee consumption – 2-3 cups daily – has been linked to lower risk of depression, Parkinson’s, and ischemic stroke, as well as a significantly reduced risk for type 2 diabetes).

Aside from taking coffee or tea breaks, the results of two new studies suggest some other ways to help support mental focus:

Keep Your Water Bottle Handy. According to studies in both young men and women, even mild dehydration can alter mood and the ability to think clearly, leaving subjects feeling “cranky” and tired (2,3). In the most recent evaluation, researchers compared the results of cognitive tests taken when participants were not dehydrated, and when they were mildly dehydrated – either from gentle walking or simply from being sedentary.

In women, mild dehydration caused headaches, fatigue, and difficultly concentrating. While the symptoms were not as pronounced for men, mild dehydration also caused some difficulty with mental tasks, as well as fatigue, tension and anxiety.

Try Aroma Therapy. Researchers report that the scent given off by the essential oils of the herb rosemary may improve mental performance (4). Subjects in the experiment were exposed to varying levels of the rosemary aroma, and blood levels of one of rosemary’s main chemicals (1,8-ceneole) was measured.

Results indicate that blood levels of the compound absorbed from the scent were related to mental performance. Higher blood levels resulted in improved results on speed and accuracy tests.

References

1. Banin PJR, et al. Dietary antioxidants and the aetiology of pancreatic cancer: a cohort study using data from food diaries and biomarkers. Gut [Epub ahead of print].
2. Ganio MS, et al. Mild dehydration impairs cognitive performance and mood of men. Br J Nutr 106:1535-43, 2011.
3. Armstrong LE, et al. Mild dehydration affects mood in healthy young women. J Nutr 142:381-8, 2012.
4. Moss M, Oliver L. Plasma 1,8-cineole correlates with cognitive performance following exposure to rosemary essential oil aroma. Ther Adv Psychopharm 2:103-113, 2012.

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Glaucoma: Looking Beyond Eye Pressure

Eye Pressure Basics

Intraocular pressure (IOP) is the fluid pressure inside the eye. Elevated IOP, called ocular hypertension, can damage the optic nerve and lead to glaucoma – and eventually, vision loss.

Not everyone with glaucoma has high IOP, however. Normal-tension glaucoma (or low-tension glaucoma) is a condition in which optic nerve damage and vision loss occur despite normal pressure.

Beyond IOP

Based on findings of two large trials (1-3), experts agree that lowering IOP reduces risk of glaucoma progression both for those with elevated IOP and with normal-tension. But research also confirms that IOP is not the only risk factor, since the disease progresses despite good IOP reductions in about 20% of cases.

This finding has led to over a decade of research to identify risk factors other than IOP that might be addressed to protect the optic nerve. Though there’s a long way to go, progress has been made in the area of optic nerve protection (neuroprotection).

Retinal ganglion cells are a type of nerve cell (neuron) that transmits visual information from the retina to the brain to form images. The long “tails” of these nerve cells, called axons, make up the optic nerve. In glaucoma, ganglion cells in the retina die or become dysfunctional. So the goal of neuroprotection is to favorably alter factors that affect nerve cell survival.

Neuroprotective Strategies: Nutrients & Botanicals

Unstable ocular blood flow is thought to be an important contributor to ganglion cell death. Studies have reported that Gingko biloba can increase ocular blood flow. In a recent study, normal tension glaucoma patients taking ginkgo were reported to lose peripheral vision (known as visual field) at a slower rate (4).

A combination of flavonoids from bilberry and pine bark has also been tested in patients with ocular hypertension (but no signs of glaucoma), with results suggesting an improvement in ocular blood flow (5).

Disturbed blood flow can produce oxidative stress, where damaging free radicals outnumber the anti-oxidants needed to quench them. There are a number of antioxidants – CoQ10, vitamin E, and others – found to be protective of retinal ganglion cells in lab studies.

Neuroprotective Strategies: Drugs & Treatments

A number of promising treatment options are being tested. One topical drug, brimonidine, slowed visual field loss in people with normal tension glaucoma better than the IOP-lowering drug timolol, even though both similarly reduced IOP (6). Brimonidine, in addition to lowering IOP, may offer neuroprotection by enhancing or activating factors that protect neurons, or by blocking release of harmful compounds.

A strategy in early testing stages is to salvage poorly functioning retinal ganglion cells. One idea is to implant encapsulated cells in the eye that produce neuro-protective substances. Another approach could be to improve ganglion function by electrical stimulation (since these cells become dysfunctional with loss of electrical stimulation and ability to pass electrical signals).

Though more research on nutritional and other treatments is needed, progress to date is encouraging. Neuroprotective strategies, combined with standard IOP-lowering treatments, may well improve the outlook for glaucoma patients in the years to come.

References

1. Collaborative Normal-Tension Glaucoma Study Group: Comparison of glaucomatous progression between untreated patients with normal-tension glaucoma and patients with therapeutically reduced intraocular pressures. Am J Ophthalmol 126:487-97, 1998.
2. Collaborative Normal-Tension Glaucoma Study Group: The effectiveness of intraocular pressure reduction in the treatment of normal -tension glaucoma. Am J Ophthalmol 126:495-505,1998.
3. Leske MC, et al. Factors for glaucoma progression and the effect of treatment: The early manifest glaucoma trial. Arch Ophthalmol 121:48-56, 2003. 
4. Lee J, et al. Effect of ginkgo biloba extract on visual field progression in normal tension glaucoma. J Glaucoma [Epub ahead of print May, 16, 2012].
5. Steigerwalt RD Jr., et al.  Mirtogenol® potentiates latanoprost in lowering intraocular pressure and improves ocular blood flow in asymptomatic subjects. Clin Ophthalmol  4:471-76, 2010. 
6. Krupin, et al. A randomized trial of brimonidine versus timolol in preserving visual function: results from the Low-pressure Glaucoma Treatment Study. Am J Ophthalmol 151:671- 81, 2011.

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Getting a Handle On Blood Pressure

Blood Pressure Basics

About 1 in 3 U.S. adults have high blood pressure according to the Centers for Disease Control, which increases the risk for heart disease, stroke, and kidney disease. It’s also been linked to a higher risk of eye conditions such as diabetic retinopathy and some types of cataract.

Blood pressure doesn’t stay the same all the time, dipping during the night, and rising when we’re excited, nervous or active. But levels that stay above 120/80 mmHg most of the time can raise the risk of health problems. (Systolic pressure is the first number, and diastolic the second number). Blood pressure also tends to go up with age, but there are ways to delay or prevent this.

Blood Pressure-Lowering Strategies

Some people with hypertension will require medication to keep their blood pressure under control. But for most of us, making healthy choices can mean avoiding, delaying or reducing the need for drugs. The key to control is losing weight, being physically active, and watching your diet.

Shedding extra weight – even just 10 pounds – can reduce blood pressure. And, generally, the more weight you lose, the greater the blood pressure reduction. Since carrying too much weight around the waist raises the risk for elevated blood pressure, watching your waistline is important too.

Regular physical activity – about 30-60 minutes on most days – can lower blood pressure by as much as 9 points. Boosting your intake of potassium and magnesium-rich foods while lowering sodium-containing foods and added salt can reduce blood pressure by another 2-9 mmHg.

Research on Nutrients & Blood Pressure

Research suggests that other nutrients may also be helpful in keeping blood pressure levels in check.

Vitamin B2 (riboflavin). From Ireland comes a report that about 1 in 10 people could significantly lower their blood pressure by raising their intake of vitamin B2. Hypertension is often linked to a particular genetic or inherited factor found in around 10% of the population.

The researchers found that for these people, B2 was able to lower blood pressure to target levels while having no adverse effects on those who didn’t have the gene (1). They saw this response even in people already taking blood pressure-lowering drugs.

The test to determine whether you fall within this genetically-at-risk group may not always be readily available. But it’s safe, say the authors, for anyone to get more of this B-vitamin from dairy or fortified foods, and/or taking a B-containing multivitamin supplement.

Vitamin C. Researchers from Johns Hopkins recently analyzed 29 controlled trials looking at vitamin C’s effect on blood pressure (2). The analysis revealed that vitamin C supplementation (median level of 500 mg) was associated with reductions of almost 4 mmHg for systolic pressure, and about 1.5 mmHg for diastolic readings. For those who already had hypertension, the benefits were even better: a decrease of nearly 5 and 2 mmHg for systolic / diastolic pressures, respectively.

Cocoa-Rich Chocolate. A research team from the UK, Australia and Harvard, analyzed 42 studies (1,297 total participants) that examined the effects of cocoa-rich chocolate on blood pressure and other cardiovascular risk factors (3).

They concluded that consuming chocolate has mild blood-pressure lowering effects, as well as other heart-healthy benefits. Some research (4) suggests that 1-2 ounces daily of dark, cocoa-rich chocolate (at least 50% cocoa) is sufficient to achieve these effects while still keeping calorie intake reasonably low.

References

1. Wilson CP, et al. Riboflavin offers a targeted strategy for managing hypertension in patients with the MTHFR 677TT genotype: a 4-y follow-up. AJCN 95:766-72, 2012.
2. Jursachek, SP et al. Effects of vitamin C supplementation on blood pressure: a meta-analysis of randomized controlled trials. AJCN 95:1079-88, 2012.
3. Hooper L, et al. Effects of chocolate, cocoa, and flavan-3-ols on cardiovascular health: a systematic review and meta-analysis of randomized trials. AJCN 95:740–51, 2012.
4. Ellinger S, et al. Epicatechin ingested via cocoa products reduces blood pressure in humans AJCN [Epub ahead of print], May 2, 2012.

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In the news: Vitamin C & Exercise, Veggies & Breast Health

Vitamin C May Help Overweight Exercisers

If you are cutting calories and moving more to shed some weight, the findings of a new study might be news you can use. The study reports that daily supplements of vitamin C may decrease heart rate during moderate exercise, helping exercisers feel less exertion and fatigue (1).

In this small but carefully conducted trial, 20 obese men and women were put on a calorie-restricted diet and assigned to receive either 500 mg of vitamin C daily or a placebo over a 4 week period. The diet was also controlled for vitamin C content.

At the beginning and end of the trial, the volunteers used a treadmill for 60 minutes at 50% intensity of predicted maximal oxygen consumption – the maximum capacity of an individual’s body to transport and use oxygen during exercise.

There was no difference in breathing between the groups, and they both lost similar amounts of weight. However the vitamin C takers had, on average, 11 fewer heartbeats per minute during exercise compared to those taking a placebo.

The group getting vitamin C also reported feeling that the treadmill session took less effort and that they felt less fatigue, as assessed by a questionnaire and by a scale that rates perceived exertion.

Perceived exertion – how hard you feel like your body is working – typically correlates with heart rate: If one is lower, the other is likely to be lower too. The researchers suggest that their findings could be a factor in helping people stick to their exercise routine, since both calorie cutting and physical activity are needed for effective weight loss.

Cruciferous Veggies May Improve Survival For Breast Cancer Patients

Members of the cabbage family, called cruciferous vegetables, include greens like mustard, collard, kale, and bok choy, cauliflower, broccoli, Brussels sprouts, turnips, watercress, radishes and more.

These veggies are well known for providing nutrients that we’re all familiar with, such as fiber, carotenoids (e.g. lutein) and folic acid. But they are also a unique source of lesser-known compounds called glucosinolates.

When digested, glucosinolates are turned into other compounds (isothiocyanates and indoles) that have anti-cancer properties. High intakes of crucifers have been associated with a lower risk of lung and colorectal cancer in some population-health studies.

Evidence linking these veggies to breast or prostate cancer has been limited. However, the newly published findings of a collaborative research project between Vanderbilt University and scientists at Shanghai Centers for Disease Control and Prevention, suggest that eating more of these veggies may benefit women who’ve had breast cancer (2).

The researchers monitored nearly 4,900 Chinese breast cancer survivors, analyzing their diets at 6, 18 and 36 months post-diagnosis.

They found that women who ate higher amounts of crucifers during the first 3 years after being diagnosed with cancer had a higher rate of survival.

Compared to women eating the least crucifers, those who had the highest daily intake had a 62% lower risk of dying from breast cancer, and a 35% reduced risk of breast cancer recurrence.

Chinese women typically eat higher amount of crucifers than do their American counterparts. They also eat different kinds of crucifers – more bok choy, turnips and greens, while broccoli and Brussels sprouts are the most common crucifers eaten by American women. Putting more crucifers on the menu might benefit all of us, especially women with a history of breast cancer.

References

1. Huck CJ, et al. Vitamin C status and perception of effort during exercise in obese adults adhering to a calorie-reduced diet. Nutr [Epub June 5, 2012].
2. Xiao SO, et al. Cruciferous vegetable consumption linked to improved breast cancer survival rates. Presented at the Annual Conference of the American Association for Cancer Research, Chicago, April 3, 2012.

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Latest Cataract Research

The “ABCs” of Cataract

A cataract is the clouding of the eye’s lens due to clumping of lens protein and discoloration of the lens because of age, smoking, sunlight exposure, the use of certain drugs, and diabetes.

The lens consists mostly of water and protein. When the protein clumps up, it clouds the lens and reduces the light that reaches the retina, causing blurred vision. Most age-related cataracts develop from protein clumping.

The clear lens also slowly colors with age. This gradual darkening doesn’t affect the sharpness of the image transmitted to the retina, but it can make it more difficult to distinguish between colors such as blues and purples.

Nuclear cataract, which occurs in the central portion of the lens, is the most common type of cataract among older people, especially women. Cataract can develop in other locations too. Cortical cataract is found at the outside edge of the lens, while posterior subcapsular cataract (PSC, the least common type) forms at the back surface of the lens beneath the lens capsule.

Helping to Keep Cataracts at Bay

Damage to lens proteins can happen gradually from a variety of causes, including the formation of free radicals due to light exposure. Antioxidants such as vitamin C and lutein / zeaxanthin are believed to play an important role in mopping up those free radicals or filtering out harmful blue light.

Two recently published studies suggest that there are steps we can take to help protect the eye’s lens. One study identifies risk factors that we can do something about, while the other report adds weight to the idea that lutein and zeaxanthin may play a protective role.

Lutein & Zeaxanthin Tied to Cataract Risk

Finnish researchers recently looked at whether blood levels of lutein and zeaxanthin are related to nuclear cataract in over 1,600 older participants (1).

People who had the highest blood levels of lutein and zeaxanthin had a 40% lower risk of having nuclear cataract, compared with the group who had the lowest blood levels.

Risk Factors linked to Cataract Types

University of Southern California researchers tracked risk factors for different types of cataract in nearly 6,000 people participating in the Los Angeles Latino Eye Study (2).

It’s no surprise that older age increased the risk for most of the cataract types except PSC, where higher systolic blood pressure and a history of diabetes were identified as risk factors.

For cortical cataract, a history of diabetes and higher hemoglobin A1c raised risk, while smoking and myopia (myopic refractive error) emerged as risk factors for nuclear type cataract. Myopia is nearsightedness, where distant objects appear out of focus. Hemoglobin A1c is the best measure of blood sugar control over time.

Finally, myopic refractive error, history of diabetes, higher systolic blood pressure, and presence of large drusen were independent risk factors for mixed cataract, where more than one lens location was involved. The presence of large drusen is predictive of developing advanced macular degeneration (AMD).

Steps We Can Take

In addition to getting regular eye exams and not smoking, make sure to:

• Eat lots of fruits and vegetables, especially the green leafy type, to increase lutein & vitamin C
• Consume low-glycemic, fiber-filled carbohydrates
• See your doctor regularly and keep blood sugar levels under control, if you have diabetes and/or high blood pressure. It’s also important to drop excess weight

References

1. Karppi J, et al. Plasma lutein and zeaxanthin and the risk of age-related nuclear cataract among the elderly Finnish population. Br J Nutr published ahead of print, 2012.
2. Richter GM, et al. Los Angeles Latino Eye Study Group. Risk factors for cortical nuclear, posterior subcapsular, and mixed lens opacities: the Los Angeles Latino Eye Study. Ophthalmol 119:547-54, 2012.

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Food, Mood and Brainpower

What Should We Be Eating for Brain Health?

What we eat seems to have significant implications for the brain: unhealthy diets may increase risk for conditions such as depression and dementia, while healthy diets may be protective. This issue of Staying Healthy highlights some of the research from the last few years to provide a practical resource for brain-friendly nutrition strategies.

The Basics: Med-Type Diet + Physical Activity

A noteworthy study (1) published in 2009 found that people who follow Mediterranean dietary patterns – that is, a diet high in fruits, vegetables, nuts, whole grains, fish, and unsaturated fat (e.g. olive oil) – are up to 30% less likely to develop depression than those who typically consume meatier, dairy-heavy fare. Olive oil lovers may also be less likely to develop mild mental impairment and Alzheimer’s, particularly when they engage in regular physical activity (2,3).

Berries, Chocolate Fight Oxidative Stress

Polyphenols, namely anthocyanins, found in berries and other red and purple fruits and vegetables may slow cognitive decline through their antioxidant and anti-inflammatory properties. In aging animals, for example, a diet high in strawberry, blueberry, or blackberry extract led to better nerve function and behavior involving learning and memory (4). Recent work suggests that berry extracts might stimulate the process by which cells clear debris, such as proteins linked to mental decline and memory loss (5). Berry anthocyanins may also reduce CVD risk by reducing oxidative stress and favorably effecting the expression of inflammatory genes (6).

Chocolate – the darker the better – seems to help scavenge free radicals and improve functioning of the arteries, likely via the polyphenols it contains. A 2010 study reported that consumption of 6 g of chocolate daily – a standard Hershey bar weighs 43 g – was linked to a 39% lower risk for stroke and heart attack (7).

Fish Oil for Mental Health, Brainpower

In a 2010 study, fish consumption correlated with a lower risk for psychotic symptoms (8). Other work suggests that fish oil may help prevent psychosis in high-risk individuals (9). Another reason to put fish on your menu? Low blood concentrations of the omega-3s are associated with smaller brain volume and poorer performance on mental acuity tests in older people (10). Oily, cold-water fish, such as salmon, herring, and mackerel, have the highest omega-3 levels.

What About Coffee and Alcohol?

Both may play a supportive role, but only when consumed in moderation. And when drinking alcohol, the best bet is to go with red wine.

The world's most widely used stimulant might do more than just wake us up: A 2011 review (11) found that daily coffee drinking cut stroke risk by 17%. Another study (12) reports that women who drink about 2 cups of coffee per day have a 15% decreased risk for depression, compared with those who rarely drink it. Limited alcohol use has been tied to a lower risk for overall and Alzheimer dementia (13), a finding supported by a recent German study (14). Moderate alcohol intake may also protect against cerebrovascular disease, with red wine having the added benefit of providing the antioxidant resveratrol.

Foods to Limit?

Diets rich in high-fat dairy, and fried, refined, and sugary foods have been found to increase the risk for depression (15-18). It's good to keep these foods to a minimum, since saturated fats and refined carbs can have detrimental effects on neurotrophins (nerve cell-protecting proteins), the immune system and oxidative stress – all factors known to play a role in depression.

Go easy on the salt shaker too. Too much salt has long been known to increase blood pressure and stroke risk, but now there is some evidence that high salt intake, as well as diets high in trans or saturated fats, can impair mental processes (19,20).

References

1. Sánchez-Villegas, A et al. Association of the Mediterranean dietary pattern with the incidence of depression. Arch Gen Psychiatry 66:1090-98, 2009.
2. Scarmeas N, et al. Mediterranean diet and mild cognitive impairment. Arch Neurol 66:216-25 2009.
3. Scarmeas N, et al. Physical activity, diet, and risk of Alzheimer disease. JAMA 302:627-37, 2009.
4. Medscape.com. New mechanism for berries' potential brain benefits. http://www.medscape.com/viewarticle/727764.
5. Berry extracts and brain aging: clearance of toxic protein accumulation in brain via induction of autophagy. Program and abstracts of the 240th National Meeting of the American Chemical Society; August 22-26, 2010; Boston, Massachusetts.
6. Basu A, et al. Berries: emerging impact on cardiovascular health. Nutr Rev 68:168-77, 2011.
7. Larsson SC, et al. Chocolate consumption and risk of stroke in women. J Am Coll Cardiol. 58:1828-29, 2011.
8. Hedelin M, et al. Dietary intake of fish, omega-3, omega-6 polyunsaturated fatty acids and vitamin D and the prevalence of psychotic-like symptoms in a cohort of 33000 women from the general population. BMC Psychiatry 10:38, 2010.
9. Amminger GP, et al. Long-chain omega-3 fatty acids for indicated prevention of psychotic disorders: a randomized, placebo-controlled trial. Arch Gen Psychiatry. 67:146-154, 2010.
10. Tan ZS, et al. Red blood cell omega-3 fatty acid levels and markers of accelerated brain aging. Neurology 78:658-64, 2012
11. Larsson SC, et al. Coffee consumption and risk of stroke: a dose-response meta-analysis of prospective studies. Am J Epidemiol 174:993-1001, 2011.
12. Lucas M, et al. Coffee, caffeine, and risk of depression among women. Arch Intern Med 171:1571-78, 2011.
13. Wayerer S, et al. Current alcohol consumption and its relationship to incident dementia Age Ageing 40:456-63, 2011.
14. Peters R, et al. Alcohol, dementia and cognitive decline in the elderly: a systematic review. Age Ageing 37:505-12, 2008.
15. Sanchez-Villegas A, et al. Fast-food and commercial baked goods consumption and the risk of depression. Pub Hlth Nutr 15:424-32, 2012.
16. Jacka F, et al. Association of Western and traditional diets with depression and anxiety in women. Am J Psychiatry 167:305-3, 2010.
17. Jacka FN, et al. A prospective study of diet quality and mental health in adolescents. PLoS One 6:e24805, 2011.
18. Frieden TR and Briss PA. We can reduce dietary sodium, save money, and save lives. Ann Intern Med 152:526-527, W182, 2010.
19. Fiocco AJ, et al. Sodium intake and physical activity impact cognitive maintenance in older adults: the NuAge Study. Neurobiol Aging 33: 829.e21-829.e28, 2012.
20. Parrott MD and Greenwood CE. Dietary influences on cognitive function with aging: from high-fat diets to healthful eating. Ann N Y Acad Sci 1114:389-97, 2007.

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In the News: Vitamin C in Heart Failure, Diabetes Risk; Vitamin D & Rhinitis

Vitamin D and Chronic Rhinitis: A Connection?

Chronic rhinitis is a common condition with multiple causes, and is characterized by inflammation of the inner lining of the nose. People with rhinitis suffer from symptoms such as a runny and itchy nose, nasal congestion, and sneezing. And chronic rhinosinusitis (CRS), inflammation of the nose and sinuses, is actually one of the most common health challenges, affecting an estimated 14% of US adults.

When it comes to vitamin effects on the immune system, vitamin D is one that takes center stage. Researchers are interested in this vitamin because it directly affects many cells (e.g. dendritic cells and macrophages) that are involved in immune and other processes underlying nasal and sinus inflammation.

Studies (1) have found low levels of vitamin D in patients with CRS and allergic fungal rhinosinusitis, and those low levels correlated with elevated levels of dendritic cells. Insufficient blood levels of vitamin D have also been observed in Afro-Americans with CRS compared with age and sex matched healthy controls.

More research is needed to better understand the relationship between vitamin D and CRS, allergic and chronic rhinitis. But in the meantime, it’s a good idea to get enough vitamin D for many reasons including bone and possibly heart health.

Low Vitamin C Linked to Inflammation in Heart Failure, Plus Diabetes Risk

Low intake of vitamin C is not uncommon, and can adversely affect our health. Just last year, for example, researchers found that heart failure patients who didn’t consume enough vitamin C had higher levels of inflammation as measured by the biomarker CRP (2).

Those heart failure patients with low C intake and more inflammation were twice as likely to die of cardiovascular disease within a one-year follow-up. Nearly 40% of the patients had inadequate intake of the vitamin.

Getting adequate vitamin C has also been linked to the risk of developing diabetes.

In the most recent study to explore this relationship, researchers looked at blood levels of vitamin C and hemoglobin A1c (one of the best measures of diabetes risk) among non-diabetic participants in the U.S. National Health and Nutrition Examination Survey (NHANES) (3).

The investigators saw a clear relationship between low blood levels of the vitamin and higher risk for diabetes (higher A1c) that was more pronounced in people 18-44 years old, in women, and in those of Hispanic origin.

Vitamin C and D Interact

In the same study, blood levels of vitamin D were also examined, since high rates of vitamin D deficiency have been found in people that are obese, and past studies have also linked low vitamin D levels to type 2 diabetes.

The link between poor vitamin C status and diabetes risk was even more pronounced in younger and female NHANES participants who additionally had lower vitamin D blood concentrations.

Interactions between these two vitamins have been identified in other studies: vitamin C is needed to turn vitamin D into its active form within the body. The current findings suggest that this interaction may be important. So be sure to get some sunshine, eat lots of vitamin C-rich fruits and vegetables, and take a daily multi-nutrient supplement that includes both vitamins C and D.

References

1. Waleed M, et al. Review. Vitamin D and chronic rhinitis. Curr Opin Allergy Clin Immunol 12:13-17, 20012.
2. Song EK, et al. Vitamin C Deficiency, High-Sensitivity C-Reactive Protein, and Cardiac Event-Fee Survival in Patients with Heart Failure. Circulation 124:A14667, 2011.
3. Kositsawat J and Freeman VL. Vitamin C and A1c relationship in the National Health and Nutrition Examination Survey (NHANES 2003-2006. J Am Coll Nutr 30:477-483, 2011.

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In the News: Olive Oil, nuts for Hearts, ‘Slow Carbs’ Cool Inflammation, Omega-3s Aid Weight Training

A Winning Combination

Three newly published studies confirm the benefits of following a Mediterranean diet – a way of eating that includes fruits, vegetables, nuts, beans, whole grains, wine, fish and olive oil. (To learn more, see Staying Healthy from Aug, 2008).

Fine-tune this diet to make sure the carbohydrates are fiber-filled and low glycemic index. Then add in some strength training and fish oil. The result? A winning combination to enhance health as we age.

Olive Oil & Nuts Help Fight Atherosclerosis

A traditional Mediterranean diet rich in virgin olive oil and nuts may be a good way to control risk of cardiovascular disease (CVD) for some people, according to Spanish researchers. The investigators recently reported initial results (1) from a long-term study tracking some 7,500 people at risk for heart disease

In the trial, 187 volunteers at risk for CVD were placed into one of three groups: one followed a traditional Mediterranean diet (Med diet) and were free to consume virgin olive oil daily as desired; A second Med-diet group supplemented their diet with about 1 ounce of nuts (walnuts, almonds and hazelnuts) daily; And those in the third group – who served as controls – were given individual counseling and educational material on how to follow a low-fat diet.

Among volunteers 55 years and older, carotid artery thickness (measured by ultrasound) was lower in both the Med-diet + olive oil and Med-diet + nut groups compared to those curtailing the overall fat in their diet. This finding, however, applied only to those who had some carotid artery thickening at the study’s start.

According to the researchers, modifying the dietary pattern of people with some thickening of the artery wall at the start of the study, gained results in one year that even pharmaceutical drugs usually don’t achieve.

All Carbs are not Created Equal

Since chronic inflammation in the body is linked to a broad range of health risks, researchers at the Fred Hutchinson Cancer Research Center set out to see whether the type of carbohydrate consumed can impact the inflammatory process (2).

Eighty healthy but obese or overweight men and women were assigned to a diet containing either slowly digested carbs or carbs that are more rapidly digested. They ate one diet for 28 days, followed by the other diet for the same amount of time. Both diets provided equal amounts of carbs, proteins, fats and calories, so that the type of carbohydrate was the sole difference between the two.

A 22% reduction in a key biomarker of inflammation, c-reactive protein or CRP, was seen during the slow carb diet period. A small, but favorable effect was also observed in levels of a hormone that helps regulate fat and sugar metabolism.

Slowly digested carbs, such as whole grains, beans, and other high-fiber foods, are also called low-glycemic index foods.  High glycemic index carbs like white flour, sugars and fiber-poor foods are more quickly digested. 

Omega-3s Enhance Strength Training in Older People

Aerobic exercise such as regular walking, running or biking, is great for the heart. But with age, it’s also important to focus on maintaining strong muscles. While the benefits of strength training have been know for decades, a new study suggests adding fish oil can maximize nerve and muscle responses to that training (3).

Women 64 or older received fish oil (400 mg EPA and 300 mg DHA daily) or placebo, before and/or during a 90-day strength program. Strength training boosted muscle torque (the rotating force needed to lift weights), but the effects were even more pronounced in those supplemented with omega-3s. The fish oil groups were better able to rise from a chair, for example, which can be difficult for the elderly.

References

1. Murie-Fernandez, M et al. Carotid intima-media thickness changes with Mediterranean diet: a randomized trial (PREDIMED-Navarra). Atherosclerosis 219:158-62, 2011. 
2. Neuhouser ML, et al. A low-glycemic load diet reduces serum c-reactive protein and modestly increases adiponectin in overweight and obese adults. J Nutr 42:369-74, 2012.
3. Rodacki CLN, et al. Fish-oil supplementation enhances the effects of strength training in elderly women. Am J Clin Nutr Epub Jan, 2012

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Young hearts & omega-3s; Antioxidants & Stroke Risk; Diet & genetic risk of AMD

Omega-3s & Heart Health in Young Women

The cardiovascular health benefits of omega-3 fatty acids are well-documented in men and older men and women. But whether a fish-rich diet is important for heart health in younger women is an area that – until recently – has received little attention.

Now, the first study to focus exclusively on women of child-bearing age reports that diets plentiful in omega-3s may help protect younger women’s hearts too (1).

The research team analyzed data from nearly 49,000 initially healthy pregnant women (average age of 30), whose dietary habits were assessed at 3 intervals over an 8 year period. The women were then followed by checking hospital records for cardiovascular-related admissions. Because very few of these women were found to take fish oil supplements, those that did were excluded from the analyses.

Women who rarely or never ate fish had 50% more cardiovascular problems than those who consumed fish regularly. And compared to women who ate fish high in omega-3s weekly, the risk of cardiovascular disease (CVD) was 90% higher for those who rarely ate these omega-3 fish sources. Because they saw a strong association with CVD in women who were still in their late 30’s, the team advises younger women to eat fish as a main meal at least twice a week.

Fish Tip: Concerned about which fish are environmentally safe to eat? Print a Seafood Watch pocket guide from Monterey Bay Aquarium’s website to help you choose ocean-friendly seafood wherever you live or travel.

Dietary Antioxidants & Stroke Risk in Women

In more good news for women, Swedish researchers have found a link between a diet high in fruits, veggies and whole grains (antioxidant rich foods) and the risk of stroke (2). The researchers used dietary information from more than 31,000 women without heart disease and 5,000 with a history of CVD to determine the women’s total antioxidant capacity – the power of the food’s antioxidants to reduce free radicals in cells.

Healthy women with the highest antioxidant intake had a 17% risk reduction for all forms of stroke (hemorrhagic and ischemic) compared to those with the lowest intake. A 57% lower risk of hemorrhagic stroke was seen in women with a history of CVD who fell within the highest ¾ of antioxidant intake.

Reducing the Genetic Risk of Early AMD

Can younger people with an inherited genetic risk for age-related macular degeneration (AMD) delay or even prevent this vision-disabling condition with the right diet? Science has no conclusive answer to this question yet, though higher intakes of lutein/zeaxanthin, as well as EPA/DHA have been linked to AMD risk reduction in a number of studies.

Dutch researchers have also found a strong link between dietary zinc, antioxidants (beta-carotene and lutein/zeaxanthin) and omega-3s, and AMD development in people who carry two of the more common gene forms (variants) known to increase susceptibility to this disease (3).

Carriers of one or both of these genetic variants who consumed more of these nutrients had a significantly reduced risk of developing early AMD. Researchers estimate that, together, these variants probably contribute to late AMD in more than 80% of cases.

The study’s authors urge younger people with family members who have AMD – to consume diets that provide good intakes of these nutrients. In addition to choosing cold water fish for EPA/DHA, zinc can be found in fortified cereals, meats, dairy products, nuts and seeds. Dark green leafy veggies such as spinach and kale, and orange veggies like pumpkin and carrots, are good sources of lutein and beta-carotene.

References

1. Strom M, et al. Fish, n-3 fatty acids, and cardiovascular diseases in women of reproductive age: A prospective study in a large national cohort. Hypertension [Epub ahead of print] Dec 5, 2011.
2. Rautainen S, et al. Total antioxidant capacity and risk of stroke: a population-based prospective cohort of women. Stroke [Epub ahead of print] Dec 1, 2011.
3. Ho L, et al. Reducing the genetic risk of age-related macular degeneration with dietary antioxidants, zinc and n-3 fatty acids. Arch Ophthalmol 129:758-66, 2011.

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In the News:
Omega-3s & IHD in Women; Physicians’ Supplement Use; B-Vitamins & Mental Function

Long Chain Omega-3s Lower IHD Risk

There are different members of the omega-3 family of fatty acids. One member, called alpha-linolenic acid, can be converted to the longer chain omega-3s EPA and DHA which are found in cold-water fish. However, the conversion of alpha-linolenic acid to EPA/DHA is limited, with only about 8-20% actually converted.

Present in flaxseeds and other plant sources, alpha linolenic acid may not be the best omega-3 choice for heart health in women according to results of a newly published trial (1).

In this prospective Danish study, dietary intake data was analyzed from over 3,200 healthy volunteers. During 23 years of study, 471 cases of ischemic heart disease (IHD) occurred.

IHD, the most common type of cardiovascular disease, refers to problems with the circulation of blood to the heart muscle. A partial blockage of one or more of the coronary arteries can result in too little oxygenated blood (ischemia), thus causing symptoms such as chest pain or shortness of breath. A complete blockage of an artery can cause a heart attack.

The researchers found that high intakes of EPA and DHA were associated with a 38% reduction in IHD risk for women. In contrast, high intakes of alpha-linolenic acid did not significantly lower the risk of IHD among women.

Do Physicians Use Supplements?

According to a newly published survey (2), a majority of US physicians within certain medical specialties appear to use supplements and recommend them to their patients.

Nine hundred physicians were surveyed; 300 cardiologists, 300 orthopedists, and 300 dermatologists. The survey results obtained were in line with the prevalence of use reported among the general public in the most recent National Health and Nutrition Examination survey, where 54% of adults said they had taken supplements in the past month.

Fifty-seven percent of cardiologists said they use dietary supplements at least occasionally, as did 75% of dermatologists and 73% of orthopedists. Regular dietary supplement use was reported by 37% of cardiologists, 59% of dermatologists, and 50% of orthopedists.

The product most commonly reported to be used was a multivitamin, but over 25% in each specialty said they used omega-3 fatty acids and over 20% said they used some botanical supplements. Seventy-two percent of cardiologists, 66% of dermatologists, and 91% of orthopedists reported recommending supplements to their patients.

B-vitamins May Slow Mental Decline

In the February issue of Staying Healthy (Protecting our Brain: Recent Research), scientists reported that a daily combination of folic acid and vitamins B6 and B12 slowed the rate of brain shrinkage or atrophy in people with mild cognitive impairment (MCI). Brain atrophy is a common sign of MCI, and can be an early warning to signs of dementia.

In a follow-up report, the Oxford and Oslo-based researchers looked specifically at participants in this intervention trial who had elevated homocysteine levels at the study’s start. Two years of B-vitamin treatment reduced levels of this amino acid, which has been previously linked to dementia.

Compared to placebo takers, people in the B-vitamin group with high initial homocysteine levels fared better on mental tests such as correct word recall, semantic memory (which refers to meaning, understanding and other concept-based knowledge), and global cognition which tests a range of cognitive functions.

References

1. Sadowa Vedtofte M, et al. Dietary alpha-linolenic acid, linoleic acid, and n-3 long-chain PUFA and risk of ischemic heart disease. Am J Clin Nutr 94:1097-103, 2011.
2. Dickenson A, et al. Use of dietary supplements by cardiologists, dermatologists and orthopedists: report of a survey. Nutr J 10:20, 2011.
3. De Jager CA, et al. Cognitive and clinical outcomes of homocysteine-lowering B-vitamin treatement in mild cognitive impairment: a randomized controlled trial. Int J of Geriatric Psych [Epub ahead of print] July, 2011.

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Latest Research on Diabetes & Nutrition

Diabetes: Once Rare, Now a Major Concern

According to an exhibition on diabetes and endocrinology at the Royal College of Physicians of Edinburgh, the first reference to diabetes in the literature dates back to 1550 BC when “the passing of too much urine” was mentioned in an Egyptian manuscript. Considerably later, in the 1st century AD, the Greek physician Aretaeus wrote the first complete clinical description of the disease. Noting the prominent symptom of excessive urination, Aretaeus coined the term diabetes, from the Greek meaning ‘siphon’ (1).

Once described as ‘rare’ by the ancient Egyptians, diabetes is now a major global health concern with over 220 million affected worldwide. Diet and exercise are key to preventing type-2 as well to help avoid complications in those who have the disease. Various issues of the Staying Healthy newsletter have reported on the impact of physical activity, the benefits of countering oxidative stress, and the consumption of low-glycemic carbohydrates to help control blood sugar levels. This issue highlights some intriguing new research on dietary strategies that could prove helpful in combating the condition. An important drug-nutrient interaction is also discussed.

Omega-3’s May Fight Insulin Resistance

Increased intake of omega-3 fatty acids was recently reported to improve biomarkers of insulin resistance2. Insulin resistance, or inefficient use of insulin by cells, can be a forerunner of type-2 diabetes. In this study of 167 men and women with altered blood lipid profiles, volunteers took either 1 gram softgels containing concentrated EPA and DHA or placebo 3 times daily for 6 months. Those taking the omega-3 had improved levels of HDL, triglycerides, and adiponectin – a protein made by fat cells. This protein helps regulate fat and glucose metabolism, and influences the body's response to insulin. Markers of insulin resistance also improved after administration of a high fat test dose.

Calorie Restriction Reduces Fat Deposits

Obesity can cause insulin resistance. That’s why weight loss is so important for people at risk for, or with, type-2. Research has also shown that excess calories can be stored as fat in the pancreas and liver, where it interferes with insulin production. This may increase the risk of developing type-2 in some people.

In a pilot study3, investigators at the University of Newcastle, gave a very low calorie diet (600 calories daily) for 2 months to 11 patients who had developed type-2 later in life. They were matched to a non-diabetic control group and monitored to measure the production of insulin and fat content of the pancreas and liver.

Scans showed that fat levels in the pancreas returned to normal. In fact, the diet appeared to reverse the symptoms of diabetes, with 64% of the participants remaining diabetes free for 3 months after the trial ended. These remarkable findings need to be tested in larger trials. Extremely low-cal diets should only be undertaken under close medical supervision.

Metformin and Vitamin B12 Depletion

There’s been increasing concern over the risk of vitamin B12 deficiency in people taking the common diabetes medication metformin4 (e.g. Glucophage). According to some studies, 10-30% of people taking this drug show evidence of decreased B12 absorption. If you’ve been taking the drug for several years or you take a high dose, it’s worth asking your health care provider to check your B12 levels. Checking blood levels of B12 should always be done with signs of B12 deficiency, especially those related to nerve problems such as numbness, pain or tingling in the hands or feet.

References

1. Graphic and exhibition information attributed to NutraIngredients, June 6, 2011, and Royal College of Physicians, www.rcpe.ac.uk
2. Derosa G, et al. Effects of n-3 PUFA on insulin resistance after an oral fat load. Eur J of Lipid Sci Tech, Epub ahead of print, June, 2011.
3. Lim EL, et al. Reversal of type-2 diabetes: normalization of beta cell function in association with decreased pancreas and liver triacylglycerol. Diabetologia 54:2506-14, 2011.
4. Kos E, et al. The effect of metformin therapy on vitamin D and B12 levels in patients with Diabetes Mellitus Type 2. Endocr Pract. Epub ahead of print, September, 2011.

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In the News: Omega-3s & Mood, Vitamin E & Lung Health, Resveratrol & Insulin

Fish Oil May Ease Depression and Anxiety

The findings of two new studies add to the growing body of evidence suggesting that fish oil may positively affect mood, behavior and mental well-being.

In the first study (1), university researchers from Australia recruited 50 people aged 65 and older with mild cognitive impairment to participate in a 6-month long trial. Volunteers received supplements of EPA-rich fish oil, DHA-rich oil, or linoleic oil daily.

Those assigned to the predominately EPA fatty acid group scored better than the linoleic acid group on the Geriatric Depression Scale – a validated questionnaire commonly used to identify depression in older people. The DHA-rich group, on the other hand, displayed improvements in verbal fluency.

These results, according to the study’s authors, indicate that both EPA and DHA omega-3 fatty acids are important for fighting symptoms of depression and boosting neurological function. Since symptoms of depression may increase the risk of progressing from mild cognitive impairment to dementia, the researchers also call for larger and longer trials to see whether fish oil can reduce the risk of dementia in this population.

Evaluating the effects of fish oil in healthy young adults was the objective of the second study (2). Ohio State University investigators enlisted 68 medical students who were given either high dose EPA plus DHA or a placebo.

Results showed a 14% reduction in levels of an inflammatory biomarker, and a 20% decrease in anxiety symptoms with the omega-3 supplement. Inflammation is believed to be involved in hormonal stress responses, and those hormones could influence a key brain region for fear and anxiety.

Vitamin E Could Decrease Lung Disease Risk

Daily supplements of vitamin E might reduce the risk of chronic obstructive pulmonary disease (COPD) by about 10% in women over 45, according to a study from Cornell University (3). COPD, which causes wheezing, shortness of breath, chest tightness and other symptoms, affects about 12 million Americans according to the National Institutes of Health.

Oxidative stress in lung tissue, the result of oxidants outnumbering antioxidants, is believed to contribute to COPD. In addition, population health studies consistently report that higher antioxidant blood levels are associated with lower risk of COPD and asthma.

The researchers analyzed data from over 38,500 women who took part in the Women’s Health Study (WHS). In the WHS, women received either 600 IU of vitamin E every other day plus 100 mg of aspirin every other day, or placebos. The finding of a 10% risk reduction was observed in both smokers and non-smokers.

Resveratrol May Boost Insulin Sensitivity

Could an antioxidant found in red wine, grapes and peanuts affect the efficiency of insulin? Though more study is needed, results from a pilot study (4) conducted in 19 type 2 diabetic men, suggests that resveratrol could prove to be helpful.

The patients took 5 mg of resveratrol or placebo twice daily for 4 weeks. Those getting resveratrol had far fewer signs of oxidative stress, and higher levels of a protein that triggers cells to take up and use the sugar glucose. Oxidative stress is thought to be a factor in insulin resistance, which renders cells less able to absorb glucose circulating in the blood stream.

References

1. Sinn N, et al. Effects of n-3 fatty acids, EPA v. DHA, on depressive symptoms, quality of life, memory and executive function in older adults with mild cognitive impairment: a 6-month randomised controlled trial. Br J Nutr 2011 Sep 20:1-12. [Epub ahead of print].
2. Kiecolt-Glaser JK, et al. Omega-3 supplementation lowers inflammation and anxiety in medical students: a randomized controlled trial. Brain Behav Immunity 2011 Jul 19. [Epub ahead of print].
3. Agler AH, et al. Randomised vitamin E supplementation and risk of chronic lung disease the Women’s Health Study. Torax 66:320-25, 2011.
4. Brasnyo P, et al. Resveratrol improves insulin sensitivity, reduces oxidative stress and activates the Akt pathway in type 2 diabetic patients. Br J Nutr 106:383-9, 2011.

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In the News: Omega-3 & Arteries, Vitamin D & Diabetes, Multis & ‘Premies’

Keeping Arteries Pliable and Elastic

While the major function of blood vessels is to deliver blood to the tissues and return it to the heart, vessels serve a variety of functions. For example, the arteries, or vessels that lead away from the heart, can expand or contract to help regulate blood pressure.

Healthy arteries are soft, pliable and elastic. This allows them to expand easily so blood can flow without much resistance. However, as we age, arteries often become stiffer and don’t open as readily. Arteries can stiffen as a consequence of arteriosclerosis (hardening of the arteries), and when the elastic fibers within the artery wall begin to fray due to mechanical stress with time. Stiff arteries can increase the risk for high blood pressure, heart attack, and stroke.

Omega-3s Reduce Vessel Stiffness

Fish oils support heart health in a number of ways. They’ve been found to lower high triglycerides and to mildly reduce elevated blood pressure. They may also help by lowering heart rate and promoting a normal heart beat rhythm.

Recently, a team of researchers from Melbourne, Australia conducted the first review of studies designed to examine whether fish oils can also be of help in arterial stiffness (1). Analyzing data from 10 clinical trials revealed that the omega-3s effectively improved measures of arterial stiffness. According to the authors, promoting vessel flexibility is one more way that omega-3s can contribute to cardio-protection.

Multis May Cut the Risk of Premature Births

Meeting vitamin and mineral needs around the time of conception is important to promote healthy pregnancy outcomes. Getting adequate folic acid, for example, can greatly reduce the chance for neural tube defects in babies. Zinc, and vitamins C and E have also been linked to lower risk of having a pre-term birth, possibly by reducing the impact of oxidative stress on the placenta.

Investigators now report that women who began using multivitamin supplements around the time of conception had a lower their risk of giving birth prematurely (2).

The researchers followed over 35,000 women participating in the Danish National Birth Cohort, recording multivitamin use during a 12 week period around the time they became pregnant. Regular multi use was associated with a 16% reduction in risk of pre-term birth, and a 20% reduction in risk of pre-term labor. There was also a 17% lower risk for giving birth to underweight babies, relative to length of gestation. The authors conclude that taking a multivitamin supplement around the time of conception may be a safe and simple strategy to improve pregnancy outcomes, similar to folic acid supplementation.

Vitamin D Shows Anti-Diabetes Potential

Beta cells in the pancreas produce insulin, and decreased functioning of these cells can predict the risk of diabetes. Because inadequate levels of vitamin D have been linked to impaired insulin secretion, researchers at Tufts University decided to study the effect of this nutrient in people at high risk for developing type 2 diabetes (3).

Ninety-two participants were assigned to receive 2,000 IU vitamin D daily with or without calcium (800 mg of calcium carbonate), or the calcium alone for 4 months. At the end of the study, a marker of beta-cell function improved by 26% in those receiving vitamin D, compared to a 14% decline in the no-vitamin D group. While further study is needed, the results could be promising for people with pre-diabetes.

References

1. Pase M, et al. Review Article. Do long-chain n-3 fatty acids reduce arterial stiffness? A meta-analysis of randomised controlled trials. British Journal of Nutrition, Epub July 6, 2011.
2. Catov JM, et al. Periconceptional multivitamin use and risk of preterm or small-for-gestational-age births in the Danish National Birth Cohort. American Journal of Clinical Nutrition 94:906-12, 2011.
3. Mitri J, et al. Effects of vitamin D and calcium supplementation on pancreatic B cell function, insulin sensitivity, and glycemia in adults at high risk of diabetes: The calcium and vitamin D for Diabetes Mellitus (CaDDM) randomized controlled trial. American Journal of Clinical Nutrition 94:486-94, 2011.

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Tips for Aging Gracefully

Keeping Age-Related Changes at Bay

While accepting the changes that come with age is one aspect of healthy aging, there are also age-related changes that we can do something about. Declines in skeletal muscle mass, strength, flexibility and balance occur naturally, for example. But it’s never too late to slow, improve or even help reverse these changes.

Regular physical exercise for its aerobic benefits is certainly part of the exercise prescription for older adults. That would include activities such as brisk walking, leisurely cycling, swimming or golf. But to improve balance, flexibility, muscle mass – and even aerobic capacity – Tai Chi and moderate strength training can also help us age as gracefully as possible.

T’ai Chi: Gentle Movements for Wellness

Developed in the 12th century in China, this ancient martial art is now practiced world-wide as a low-impact, aerobic form of exercise for promoting health. In China, it’s considered the most beneficial exercise for older people because it’s gentle and readily modified to fit individual health needs. It’s even widely practiced in Chinese hospitals and health clinics.

The simplest t’ai chi style consists of 13 movements. When done in a slow, relaxed and flowing series of movements, flexibility, suppleness and balance are emphasized rather than strength. Deep, relaxed breathing in a focused manner helps keep the mind calm and alert (1).

T’ai Chi Research Findings

The National Center for Complementary and Alternative Medicine, a branch of the National Institutes of Health, has sponsored studies of t’ai chi that have investigated its effects in people with osteo-arthritis, for instance, as well as stress reduction and well-being in cancer survivors. But research also shows that it can generally improve quality of life and general functioning in many people.

In a 2008 review (2) of 26 studies examining the effects of t’ai chi on blood pressure in patients with or without cardiovascular conditions, 22 of the studies reported reductions in blood pressure without any adverse effects. The reviewers concluded that t’ai chi may serve as a practical complement to conventional methods for managing hypertension. Other studies have reported benefits in older healthy adults with sleep problems (3), and higher bone-mineral density in postmenopausal women who practice t’ai chi long-term (4).

If t’ai chi sounds appealing, websites for the following organizations may be helpful: American T’ai Chi Association (www.americantaichi.net); T’ai Chi for Health (www.taichiforhealthcommunity.org); and International Taoist T’ai Chi Society (www.taoist.org).

Strength Training For Stronger Muscles

Skeletal muscles reach peak mass by the 3rd decade of life, and muscle fibers decrease in size and number with each subsequent decade. Up to 30% of muscle mass may be lost by the time we’re 80. It’s clear that strength training increases muscle size and strength, but what kind of a program should we be following?

Experts generally suggest doing a single set of 10-15 repetitions using 8-10 different exercises performed 2-3 times weekly (5). And the training program should involve all major muscle groups.

It doesn’t have to be complicated, and a great resource for women wanting to get started is the revised edition of Strong Women Stay Young by Miriam Nelson, PhD of Tufts University. Dr. Nelson's research, published in the Journal of the American Medical Association, show that strength training does more than help firm up sagging upper arms. It also improves balance, energy, and helps control weight. The strength training program can be done at home with small free weights.

References

1. Horowitz S. T’ai Chi, Gentle movements for wellness. Altern Compl Therapies 15:75-80, 2009.
2. Yeh GY, et al. The effect of tai chi exercise on blood pressure: A systematic review. Prev Cardiol 11:82-89, 2008.
3. Irwin MR, et al. Improving sleep quality in older adults with moderate sleep complaints: A randomized controlled trial of tai chi. Sleep 31:1001-08, 2008.
4. Wayne PM, et al. The effects of tai chi on bone mineral density in postmenopausal women: A systematic review. Arch Phys Med Rehabil 88:673-80, 2007.
5. Nied RJ and Franklin B. Promoting and prescribing exercise for the elderly. Am Fam Phys 65:419-26, 2002.

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Tackling Health Risks in Teens & Young Adults

Hypertension on the Rise in Younger People

Traditionally, high blood pressure has been considered an adult disease, not a condition common among young adults or teens. However a new study (1) reports that nearly 1 in 5 younger adults have blood pressure readings that meet the definition of hypertension. Alarmingly, only about ¼ of those with high blood pressure in the study were aware that they had it.

Researchers from the University of North Carolina analyzed data on more than 14,000 younger adults aged 24-32, and found that 19% had blood pressure readings higher than 140/90. Previous estimates were about 4% in this age group. The study authors believe that the obesity epidemic is behind their findings, because hypertension is strongly associated with overweight. Due to the huge increase in obesity among children and teens, many experts warn that high blood pressure is now a significant health concern for them as well.

Tips for Fighting Overweight

One of the key reasons that many kids & teens carry around extra pounds is lack of physical activity, plain and simple. Of course the right eating plan can pay big dividends too. Have an overweight young person in your family? Here are some resources that can help:

• Explore the government website www.letsmove.gov/ for ‘how to’ information and motivational tools.
• On that same website, or at www.MyPlate.gov, you’ll find information on the new graphic designed to show what portions of foods make for healthy eating. Replacing the harder to understand Food Pyramid, the “plate” (see picture) is great for teens in that it’s simple, and it doesn’t say what you have to eat or what you can’t eat. And you don’t have to worry about portion sizes – just follow the pro-portions, use an 8” plate, and you’ve got it made.
• For a more structured dietary approach, try this site which gives practical advice about the DASH diet (Dietary Approach to Stop Hyper-tension). Richer in potassium, magnesium, calcium, protein, and fiber compared to the typical diet, DASH has not only been shown to lower blood pressure, it may help teens stay slim as well. A newly published study (2) found that adolescent girls (aged 9-19) whose food intake most resembled DASH, had the smallest gains in body mass index (BMI) over 10 years, and the lowest BMIs at the end of the follow-up period.

Also keep in mind that teens can benefit from a calcium, magnesium and vitamin D supplement, if they’re not meeting recommended intakes from food alone. And although the evidence for fish oil reducing blood pressure is preliminary, a fish oil supplement is probably a good idea for those who shy away from fish.

Higher Protein Breakfast May Cut Snacking

While everyone knows that eating breakfast is important, it’s estimated that 60% of teens regularly skip this meal. A recent study (3) that monitored brain signals associated with motivation and eating behavior among obese teen girls, found differences in those signals 3 hours after eating a high protein breakfast.

Passing up breakfast has been associated with unhealthy snacking, overeating and weight gain. These findings provide more evidence that a higher intake of protein at this meal can be a valuable strategy to help control appetite and regulate food intake.

References

1. 1. Nguyen QC, et al. Discordance in national estimates of hypertension among young adults. Epidemiol 22:532-541, 2011.
2. Berz JP, et al. Use of a DASH food group score to predict excess weight gain in adolescent girls in the National Growth and Health Study. Arch Pediatr Adolesc Med 165:540-46, 2011.
3. Leidy HJ, et al. Neural responses to visual food stimuli after a normal vs. higher protein breakfast in breakfast-skipping teens. Obesity [ePub May, 2011].

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In the News: Healthy Flavonoids, Vitamin D & AMD Risk

Flavonoids are a “Hot” Research Topic

Flavonoids, also referred to as bioflavonoids, are polyphenol antioxidants found naturally in plants. Flavonoids are nutrients found in fruits, vegetables, herbs, wine, cocoa and teas. There are many different families of Flavonoids, and various families are thought to have protective effects against chronic diseases. We consume an estimated 190 mg of Flavonoids daily, and researchers are trying to better understand their contribution to health and to determine optimal intakes. The results of two new studies, which focus on citrus Flavonoids, illustrate the potential benefits of Flavonoids and suggest that higher intakes are warranted.

Citrus Flavonoids Lower Blood Pressure

Researchers studied the effects of orange juice (OJ) and its major flavonoid, hesperidin, on blood pressure and blood vessel function in overweight but otherwise healthy men (1). About 1/3 of the men had elevated blood pressure, but were taking no anti-hypertensive medications.

During 3 successive 4 week periods, the men drank either 17 oz of orange juice daily, a control drink with 300 mg hesperidin capsules (the same amount as the orange juice contained), or a control drink along with a placebo capsule.

At the end of both the OJ and hesperidin test periods, diastolic pressure was significantly lower than after the placebo period. Diastolic pressure (the second number in blood pressure readings) measures the pressure in blood vessels between heart beats, when the heart is resting. Even a decrease of just 3-4 points in diastolic pressure could translate into a 20% reduction in the incidence of coronary heart disease.

The researchers also tested a variety of measures of blood vessel activity, including the ability of vessels to dilate. Both OJ and hesperidin showed positive effects compared to placebo.

More Flavonoids, Less Inflammation

In another study (2), researchers examined flavonoid intake and blood markers of inflammation in a large group of women. The investigators found that women eating the highest amount of total flavonoids had the lowest blood levels of one marker (IL-8). Among foods, higher intakes of grapefruit were linked to lower levels of two more markers (CRP and TNF-R2). Finally, citrus flavonoids in particular were associated with lower levels of another inflammatory marker (IL-18).

Why is this finding important? Well, most people are aware of acute inflammation – the redness, swelling and pain encountered with injury. However, it’s long-term unresolved inflammation that is believed to underlie many chronic diseases, including ocular conditions such as age-related macular degeneration (AMD), dry eye and glaucoma.

Vitamin D May Protect Against AMD in Women

Higher blood levels of vitamin D are associated with a lower risk of developing AMD, according to new research (3). Looking at vitamin D and AMD status in over 3,000 postmenopausal women, investigators found that higher blood levels of this “sunshine vitamin” decreased the risk of early AMD in women under 75. For those over 75, the association was borderline.

In terms of vitamin D intake from supplements and foods, those consuming the highest amount (on average about 600 IU) daily, had a 59% lower risk of AMD compared to those getting the least (about 300 IU on average).

This is the second study to report a relationship between vitamin D and AMD. The vitamin has anti-inflammatory actions, and inflammation plays a role in AMD development. Specifically, the vitamin may interfere with the destructive inflammation that happens in the early stages of the disease at the interface of the retina’s blood supply (choroid) and the pigment-containing cells of the retina.

References

1. Morand C, et al. Hesperidin contributes to the vascular protective effects of orange juice: a randomized crossover study in healthy volunteers. Am J Clin Nutr 93:73–80, 2011.
2. Landburg R, et al. Selected dietary flavonoids are associated with markers of inflammation and endothelial dysfunction in U.S. women. J Nutr. 141:618-25. Epub Feb 16, 2011.
3. Millen AE, et al. Vitamin D status and early age-related macular degeneration in postmenopausal women. Arch Ophthalmol 129:481-89, 2011.

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Omega-3 Lowers AMD Risk: Strongest Evidence to Date

Good Habits + Omega-3: A Winning Strategy

Staying physically active, eating well and not smoking can improve your chances of avoiding age-related macular degeneration (AMD), according to study findings reported in the previous issue of Staying Healthy.

In terms of eating habits, that study found benefit for people who ate fruits and vegetables (sources of eye-healthy lutein and polyphenols), and whole grains, which have less impact on blood sugar fluctuations. Also beneficial was avoiding excessive salt and added sugar, using low fat dairy, and keeping saturated fats to a minimum.

While the researchers didn’t look specifically at intake of fatty acids from fish, many other studies have. And the results have been pretty consistent: getting enough omega-3 fats can also up your odds of keeping the macula healthy as we age.

Adding to that evidence is new research from Harvard showing that regular omega-3 intake can significantly lower the risk of AMD by up to 45%. It’s the strongest evidence to date, according to the investigators, that the omega-3s may actually help prevent AMD.

Investigators Follow Women with no AMD

The Harvard research team analyzed information on eating habits collected from over 38,000 women who participated in the Women’s Health Study. None of the women, who were 55 years of age on average, were diagnosed with AMD at the beginning of the study. After 10 years of follow-up, 235 of the participants had developed signs of the disease, most in the early stages of AMD development.

The investigators found that women who regularly consumed DHA, EPA and fish had a 35% to 45% lower risk of visually significant AMD. Looking at fish intake, one or more servings per week was associated with a 42% reduction in risk compared to one or fewer servings per month.

The team also observed that the apparent benefit of EPA and DHA was more pronounced in women who consumed higher levels of omega-6 intake. This suggests that both the level of omega-3 fats and its ratio to omega-6 fats is important in determining the risk of AMD.

How Might Omega-3 Help Protect the Macula?

There are many ways that DHA and EPA might act to decrease AMD risk. For example, both DHA and EPA influence inflammatory and immune processes thought to play a role in the development of the disease. These fatty acids enhance production of compounds called resolvins and neuroprotectins, which dampen and resolve inflammation. Both fatty acids may also help maintain or improve blood flow in the eye’s choroid – a highly vascular tissue layer located under the retina.

AMD Prevention is Key

An estimated 9 million US adults 40 years and older show signs of AMD, and treatment options are limited.

Most cases of severe vision loss are associated with advanced AMD – either the dry or wet form – which affects an estimated 1.7 million people. For those with moderate risk of developing advanced AMD, the antioxidant combination tested in AREDS has been shown to slow progression of the disease. There are also some treatment options for those with late-stage wet AMD.

But, for the additional 7.3 million who have early AMD there is no recognized means of prevention. That’s why it’s important to determine whether adopting a healthful lifestyle, including getting enough omega-3 and lutein, could make a difference in helping prevent this disease.

References

Christen WG, et al. Dietary omega-3 fatty acid and fish intake and incident Age-Related Macular Degeneration in women. Archives of Ophthalmology. March 14, 2011. [Epub ahead of print]

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In the News: Healthy Habits & AMD, Diet & Kidney Function

Healthy Habits May Lower AMD Danger

Habits that help protect your heart – eating well, exercising and not smoking – are also good for your eyes according to new research from the Carotenoids in Age-Related Eye Disease Study (CAREDS) (1). The researchers concluded that adopting these lifestyle habits could reduce the number of people who develop advanced AMD, the leading cause of blindness among older Americans.

Of the 1,300 CAREDS participants who had provided detailed dietary and lifestyle data 6 years earlier, about 200 of them now showed signs of AMD – all but a few of them in the early stages of the disease.

Participants were divided into groups based on the quality of their diets. Points were awarded for eating vegetables, fruits, whole grains, and low-fat dairy, with points deducted for added sugar, salt and saturated fats. The group who ate the healthiest lowered their risk of AMD by 46%.

In terms of physical activity, the most active women were 54% less likely to develop the disease. Smoking was not a very strong risk factor when considered alone, but it did become important when grouped together with diet and exercise. Women who scored the highest on a combined healthy living index reduced their AMD risk by a striking 71%.

A healthy lifestyle could help prevent AMD by reducing blood pressure, inflammation and oxidative stress, according to the CAREDS researchers. They also point out that consuming more lutein and zeaxanthin favorably affects the eye’s macula, making it less vulnerable to oxidative damage.

Plant-Based Diet Best for Kidney Disease

People with chronic kidney disease are often advised to reduce their intake of phosphorus. That’s because impaired kidneys are less able to eliminate this mineral, causing blood levels to rise. Elevated blood phosphorus can lead to brittle bones, and is also linked to poorer outcomes for chronic kidney disease patients and those undergoing dialysis.

It can be challenging to restrict phosphorus intake since the mineral is found in so many foods and the dietary plan can be complex. However results from a new study (2) indicate that replacing meat and dairy sources of protein with plant-based alternatives can reduce blood phosphorus in kidney disease patients.

Telling patients just to use more vegetarian vs. meat products and less processed foods would be much easier than asking them to follow the complex renal plan, explained the study investigators.

This small trial compared the effects of a diet rich in plant protein to one higher in animal protein. Even though both diets provided equivalent amounts of protein and phosphorus, only the plant-based eating pattern lowered blood levels of the mineral. That’s probably due to the fact that most plant phosphorus is in the form of a compound (phytate) which isn’t absorbed.

The researchers were even more excited to find that the plant-based diet lowered levels of a phosphorus-regulating hormone (FGF-23). This hormone rises as kidney function declines, and is associated with increased mortality in kidney patients.

Can Diet Help Prevent Kidney Disease?

Findings from another new study suggest that a plant-based diet may also help prevent people from developing kidney disease in the first place (3).

In this study of over 3,100 women, those eating the most red and processed meats, saturated fats and added sugar had about twice the risk of developing changes that signal a decline in kidney function.

References

1. Mares JA, et al. Healthy Lifestyles Related to Subsequent Prevalence of Age-Related Macular Degeneration. Arch Ophthal Dec 13, 2010 [Epub ahead of print].
2. Moe SM, et al. Vegetarian compared with meat dietary protein source and phosphorus homeostasis in chronic kidney disease. Clin J Am Soc Nephrol 6:257-64, 2011.
3. Lin J, et al. Association of dietary patterns with albuminuria and kidney function decline in older white women. Am J kidney Dis 57:245-54, 2011.

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In the News: Berries & Vitamin D

Think Purple and Red. Think Health.

Can putting more purple and red produce on the menu really help maintain good health? Mounting evidence says that it can.

Certain red and purple fruits and vegetables owe their color to a type of naturally occurring bioflavonoid called anthocyanins. Bilberries, blueberries, and blackberries are loaded with this flavonoid. Other good contributors include grapes, cherries, raspberries, strawberries, plums, cranberries, and blood oranges. Choosing red cabbage, red onions, and red wines will boost your intake too.

Consuming more anthocyanins, according to two newly published studies, may reduce the risk of developing Parkinson’s as well as support healthier blood pressure.

An Anthocyanin-Rich Diet and Parkinson’s

Experimental studies suggest that anthocyanins may help protect nerve cells and enhance the connections between these cells. Now, Harvard School of Public Health investigators say that if their findings are confirmed, anthocyanins may be one way to reduce the risk of Parkinson’s (1).

A degenerative disease affecting movement and balance, Parkinson’s involves nerve cells in several parts of the brain and nervous system – particularly those that use the chemical messenger dopamine.

After more than 20 years of tracing nearly 50,000 men from the Health Professional Follow-up Study and over 80,000 women from the Nurses’ Health Study, the Harvard team reports that men eating the most flavonoids lowered their risk by 35%. Risk reduction was observed in both women and men who regularly consumed anthocyanin-rich foods specifically.

Anthocyanins Linked to Reduced Blood Pressure

Also led by Harvard researchers, a second study found that the highest intake of anthocyanins – mainly from blueberries and strawberries – reduced the risk of high blood pressure by 12% among people over 60 (2).

The information about blood pressure and diet came from about 150,000 U.S. health professionals. After crunching the numbers, the researchers found that the highest average intakes of anthocyanins ranged from 16 to 21 mg per day – a rather modest amount since a normal serving of blueberries provides in excess of 500 mg. What’s needed now, says this team, are studies that test whether optimal doses of anthocyanin-rich foods can prevent hypertension.

Anthocyanins seem to help regulate blood pressure by influencing the flow of blood through vessels, and the vessels’ ability to expand and contract as needed.

A Role for Vitamin D in Urinary Tract Health?

Adequate vitamin D may increase the body’s immune response, and in doing so, help protect against urinary tract infections (UTIs), according to preliminary but intriguing research from Sweden (3). After menopause, women are more prone to UTIs. And they often have low blood levels of vitamin D as well.

The Swedish scientists measured amounts of a protective, anti-microbial substance made by bladder cells in postmenopausal women before and after they were given vitamin D supplements for 3 months.

Levels of the protective substance went up when the vitamin D enriched bladder tissue was exposed to E. coli bacteria, suggesting that vitamin D prepares the bladder to mount a stronger and faster immune response when bacteria enter the bladder.

In light of the emerging resistance to antibiotics that are used to treat UTIs, we need to fully explore whether improving vitamin D in older women really helps fight off these infections.

References

1. Gao X, et al. Habitual intake of dietary flavonoids and risk of Parkinson disease. Am Acad of Neurology Meeting Abstract, 2011.
2. Cassidy A, et al. Habitual intake of flavonoid subclasses and incident hypertension in adults. Am J Clin Nutr 93:338-47, 2011.
3. Hertting O, et al. Vitamin D Induction of the human antimicrobial peptide cathelicidin in the urinary bladder. PLoS ONE 5:e15580, 2011.

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Protecting our Brain: Recent Research

Brain Volume and Mental Function

With age, the brain tends to atrophy and shrink in volume. For those over 70, 16% experience mild cognitive impairment (MCI), characterized by issues with memory, language and other mental functions. And over ½ of those with MCI progress to Alzheimer’s.

Two new studies suggest that there may be steps we can take to help protect our mental abilities like thinking, reasoning and remembering – all part of what’s termed cognitive function.

Walking To Help Preserve Mental Function

Findings from a University of Pittsburgh study provide more evidence that physical activity can play a key role in protecting our brain as we grow older (1).

The investigators did additional research on nearly 300 of the 1,400+ people who are part of the long term Cardiovascular Health Study. The participants, who were all cognitively normal at the beginning of the study, underwent MRI brain scans 9 years later. After 13 years, they were tested for MCI or dementia.

Based on weekly walking distances, participants were divided into four groups. The average number of blocks walked per week was 8, 21, 45 and 156 in the groups. After the brain scan, only those in the group with the highest amount of walking showed significantly greater volumes in three gray matter areas of the brain.

At the 13 year mark, about 39% of the participants had developed some degree of MCI while the rest still had normal cognition. The researchers found that the larger gray matter volume observed with physical activity reduced the risk of cognitive impairment 2-fold. This study was conducted in people with an average age of 78 – a time of life when the risk for brain deterioration and dementia are greatest. So, it’s tempting to think that starting a walking program even earlier in life may be a good way to help preserve our brain as it ages. For certain, physical activity will benefit the heart, help keep weight down, and reduce the risk of getting a number of chronic diseases.

Extra B-Vitamins May Slow Dementia

Though not all studies examining the effects of B-vitamins in cognitive impairment have reported benefit, recent findings (2) from Oxford University’s Project to Investigate Memory and Aging are heartening. They suggest that supplemental B-vitamins can slow the progress of dementia.

The trial enrolled individuals over 70 with MCI who were given 3 B-vitamins (folic acid, vitamins B6 and B12) or placebo. Of the 271 participants, 168 had MRI brain scans at the start and end of the two-year study.

The brain scans showed that the B-vitamin group had a significantly slower rate of brain atrophy and shrinkage over time compared to placebo. The researchers also reported that at the end of the trial, a greater rate of brain deterioration was linked with lower test scores measuring cognitive function.

The B-vitamins lowered levels of homocysteine – the artery damaging compound once thought to raise the risk of heart disease and stroke. There is evidence, though, that homocysteine is a likely culprit in dementia and some eye diseases like AMD and glaucoma. In this study, among those with the highest homocysteine levels at the study’s start, taking B-vitamins reduced the rate of brain shrinkage by ½ compared to taking placebo.

Accelerated brain atrophy is often seen in people with MCI who go on to get Alzheimer’s. More studies will be needed to see whether B-vitamins can delay the progression of MCI to Alzheimer’s disease.

References

1. Erickson KI, et al. Physical activity predicts gray matter volume in late adulthood: the Cardiovascular Health Study. Neurology 75:1415-22, 2010.
2. Smith AD, et al. Homocysteine-lowering by B vitamins slows the rate of accelerated brain atrophy in mild cognitive impairment: a randomized controlled trial. PLoS One 5:e12244, 2010.

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Diet, Lifestyle and Gout

Gout is on the Rise; Diet & Lifestyle Can Help

Gout, one of the oldest known forms of arthritis, has been become more widespread over the past 2 decades according to research presented at a recent American College of Rheumatology Annual Meeting.

During gout attacks, crystals of a naturally occurring chemical called uric acid (urate) accumulate in joints – commonly in the toes – causing swelling, pain and inflammation. Urate in blood serves as the source of these uric acid crystals: some people make too much urate, while others have a hard time getting rid of it. But whatever the cause, estimates from the National Health and Nutrition Examination Survey (NHANES) are that 32 million US adults have high blood levels of uric acid, a stepping-stone to gout.

Compared with women, men have a greater risk of developing gout. But women can get gout too, often after menopause when estrogen levels decline. Estrogen helps the kidneys excrete uric acid, so uric acid levels can rise in postmenopausal women.

A number of medications can help manage gout, but diet and lifestyle factors play a significant role as well.

Beverages: Some to Curtail, Others OK

Restriction of alcoholic beverages is important in the management of gout. Too much alcohol may reduce excretion of uric acid, and beer in particular contains a high level of purines. Dietary purines are a source of uric acid when they’re metabolized in the body. A glass of wine is usually considered harmless.

A large prospective study found that drinking coffee was associated with a decreased risk of gout, while higher intake of sugar-sweetened soft drinks or fructose was strongly associated with an increased risk. These findings suggest that coffee is probably alright for gout sufferers. But intake of fructose-sweetened drinks should be limited as they appear to reduce uric acid excretion. And everyone – but especially those with a history of kidney stones due to uric acid – should drink an ample amount of water daily to help flush away urate crystals.

Gradual Weight Loss is the Goal

Studies report that gout is often associated with the metabolic syndrome – a condition characterized by abdominal fat, Insulin resistance and high triglyceride levels. Lowering triglycerides with a weight-loss diet has been shown to increase the kidney’s excretion of urate in patients with gout.

Excess weight is a risk factor for gout, and many gout sufferers are, in fact, overweight. But the idea is to shed excess pounds gradually (around 2 ½ lbs monthly) through exercise and calorie cutting. Crash dieting with rapid weight loss could lead to ketoacidosis (a build-up of ketones) and provoke gout attacks.

Watching Purine Intake: Meat and Seafood

Many physicians advise gout patients to reduce their intake of animal-source purines like meats and seafood, which can lower blood urate levels modestly. Some doctors also suggest avoiding other purine-rich foods such as peas and cauliflower. Getting individualized dietary advice is the best bet for those with gout.

What about prevention? One research team followed 47,000+ men with no prior history of gout over a 12-year period. Participants who ate the highest amount of meat were 40% more likely to develop gout than those who ate the least. And those eating the most seafood were 50% more likely to develop it. In this study, though, not all purine-rich foods were associated with an increased risk of gout. Consuming peas, beans, spinach, mush-rooms and cauliflower did not raise gout risk.

Bring on the Bing

Lastly, a pilot study in healthy women found that eating sweet Bing cherries lowered blood urate levels. In a second study, consuming 2 servings of the cherries for a month had anti-inflammatory effects in women. Both findings suggest that this fruit could have beneficial effects for those with high urate levels or gout.

Resources:

1. Tausche AK et al. Gout—current diagnosis and treatment. Dtsch Arztebl int 106:549-55, 2009.
2. Choi HK et al. Purine-rich foods, dairy and protein intake, and the risk of gout in men. NEJM 350:1093-103, 2004.
3. Schumacher HR Jr, Chen LX. The practical management of gout. Cleve Clin J Med 75 Suppl 5:S22-5, 2008.    
4. Keith MP, Gilliland WR. Updates in the management of gout. Am J Med 120:221-24, 2007.
5. Jacob RA et al. Consumption133(6):1826-9 of cherries lowers plasma urate in healthy women. J Nutr 133:1826-9, 2003.

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Trio of Nutrients May Help Combat Type 2 Diabetes

Take Positive Steps to Counter Type 2

When it comes to preventing type 2 diabetes – or controlling blood sugar in those who already have it – the factors with the biggest punch by far are pretty straight forward: lose weight if you need to, exercise regularly, and eat a healthy Mediterranean or low glycemic index diet.

In addition, researchers continue to explore the contribution of individual nutrients in combating type 2. This issue of Staying Healthy highlights recent findings related to omega-3 fats, magnesium and cinnamon.

New Understanding of Omega-3 Benefits

The American Diabetes Association (ADA) already recommends that people with diabetes eat 2-3 servings of fish weekly. That’s because studies have shown that consuming more omega-3s can help stave off coronary heart disease in diabetics, who have a greater risk of developing cardiovascular conditions than non-diabetics.

New research also points to a potential role for the omega-3 fatty acids EPA and DHA in helping to activate anti-diabetic genes (1). The study, carried out in animals, found that these omega-3 fatty acids activate genes that help regulate fat cells and maintain blood sugar balance. The factor activated by the omega-3s (transcription factor PPARy) is one that’s targeted by a number of anti-diabetic drugs. If the findings hold true in humans, it may mean additional benefits for those meeting ADA guidelines for omega-3 intake.

Study Underscores Importance of Magnesium

Low blood levels of magnesium occur in about 25-30% of people with type 2, and are more common in those with poorly controlled diabetes. Many studies have also reported that a better intake of this mineral can lower the risk of developing type 2. Results from a long term study appear to confirm that association (2).

Led by investigators at the University of North Carolina at Chapel Hill, the study recruited nearly 4,500 young adults 18-30 years of age who were free of diabetes and assessed their intake of dietary magnesium. Three hundred and thirty cases of diabetes developed over the next 20 years of follow-up.

People with the highest magnesium intake were 47% less likely to acquire type 2 compared to those eating the least. Those getting the most averaged about 200 mg of magnesium for every 1,000 calories consumed compared with the lowest intake group who got about 100 mg of the mineral per 1,000 calories.

High magnesium consumers also had lower blood levels of inflammatory markers, and less insulin resistance (the inability of some cells to respond to insulin). One of magnesium’s jobs is to help insulin move glucose out of the blood stream and into cells.

As mentioned in the March Staying Healthy, a recently published survey found that less than ½ of US adults consume recommended magnesium levels. Dietary sources include beans, whole grains, broccoli, squash, and green leafy veggies, seeds, and nuts (especially almonds). Dairy, meats, chocolate, and coffee also provide magnesium, as does "hard" water.

Cinnamon Useful for Some Diabetics

From the UK comes a study suggesting that cinnamon may be useful in patients with poorly controlled type 2 diabetes (3). Fifty eight type-2 patients with high HbA1c (a key measure of glucose control) were given 2 grams of cinnamon or placebo daily for 3 months. Compared to placebo-takers, those supplemented with cinnamon experienced a significant reduction in HbA1c as well as a decrease in blood pressure (both systolic and diastolic values).

According to the researchers, this spice could be a useful addition to conventional drugs for diabetics who have trouble controlling their blood sugar levels.

References

1. 1. Yu, YH et al. The function of PPARy and dietary fish oil effect on the expression of lipid and glucose metabolism related genes. J Nutr Biochem (Epub ahead of print) Oct, 2010.
2. 2. Kim DJ et al. Magnesium intake in relation to systemic inflammation, insulin resistance and the incidence of diabetes. Diabetes Care (Epub ahead of print ) Aug, 2010.
3. 3. Akilen R et al. Glycated hemoglobin and blood pressure-lowering effect of cinnamon in multi-ethnic Type 2 diabetic patients in the UK: a randomized, placebo-controlled, double-blind clinical trial. Diabetes Med 27:1159-67, 2010.

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In the News: Blueberries & Metabolic Syndrome, Cancer Risk & HDL, Caffeine & IOP

Healthful Blueberries: Bang for the Buck

Metabolic syndrome is a constellation of disorders that can raise the risk of developing diabetes and cardiovascular disease (CVD). High blood pressure, high triglycerides, abnormal cholesterol, obesity and lots of fat in the abdomen and waist area are among the associated problems. What’s alarming is that up to 25% of Americans are thought to fit the profile for metabolic syndrome, mostly due to the obesity epidemic we face.

Weight loss and exercise are our biggest weapons in the fight against metabolic syndrome. Results of a new study (1) now suggest that regularly eating blueberries can also help reduce some of the adverse health risks associated with this syndrome.

In the study, overweight people with the syndrome who consumed a beverage providing 50 g of freeze-dried blueberries daily for 8 weeks had greater decreases in their blood pressure and biomarkers for inflammation compared to people getting a placebo beverage. Oxidized LDL cholesterol in the blood, which can directly damage the lining of arteries, was also significantly decreased in the “blueberry” group.

Blueberries, like bilberries, are very high in polyphenols – compounds that are believed to be responsible for the berries’ heart-healthy benefits. The volunteers in this study consumed the equivalent of a little more than 12 ounces of blueberries daily – an amount that is fairly easy to achieve.

Higher HDL May Mean Lower Cancer Risk

According to an analysis of 24 randomized, controlled trials, HDL cholesterol (the so-called “good” cholesterol) might reduce the risk of cancer (2). The authors, from Tufts University, report that cancer risk dropped 36% for every 10 mg/dl increase in HDL.

It’s not understood how HDL might help combat cancer. One theory is that it could have antioxidant and anti-inflammatory effects. Or HDL may help the immune system search out and destroy abnormal cells with the potential of growing into tumors. The researchers point out that their study can’t prove that low HDL levels up the risk of cancer. However while we await further findings, it’s still a good idea to keep HDL levels as high as possible since it’s already known to help protect against heart disease. Optimum levels for cardio-protection are at least 60 mg/dl, with higher levels even better.

How can we boost HDL? Regular exercise, weight loss (for those overweight), and not smoking have the biggest impact on bolstering HDL levels. Moderate alcohol consumption has a modest effect, and omega-3 might be helpful as well. A recent study found an association between omega-3 intake and HDL, with a 2.5 mg/dl increase in HDL observed for every 1% increase in omega-3 consumption (3).

High Eye Pressure & Caffeine: Bad Combo?

Moderate coffee intake – about 2-3 cups daily or the caffeine equivalent of about 250 mg – appears to be safe for most people. At that level of intake, the bulk of the evidence indicates that caffeine isn’t cancer-causing, doesn’t cause or worsen CVD or hyper-tension, and doesn’t raise the risk of fibrocystic breast disease or bone loss. Caffeine may even have some benefits: it’s been linked to a lower risk of type-2 diabetes, gallstones in men, and Parkinson’s disease.

For people with glaucoma and elevated intraocular pressure (IOP) however, regular or excessive caffeine intake may not be a great idea. In an analysis of 6 trials, the IOP of normal individuals did not go up when measured 30, 60 and 90 minutes after ingesting caffeine (4). IOP did, however, rise significantly at these time points when people with glaucoma or ocular hypertension were given caffeine.

References

1. Basu A, et al. Blueberries decrease cardiovascular risk factors in obese men and women with metabolic syndrome. J Nutr 140:1582-87, 2010.
2. Jafri H, et al. Baseline and on-treatment high-density lipoprotein cholesterol and the risk of cancer in randomized controlled trials of lipid-altering therapy. J Am Coll Cardiol 55:2846-54, 2010.
3. Buyken AE, et al. Modifications in dietary fat quality are associated with changes in serum lipids of older adults independently of lipid medication. J Nutr 140:88-94, 2010.
4. Li M, et al. The effect of caffeine on intraocular pressure: a systematic review and meta-analysis. Graefes Arch Clin Exp Ophthalmol [Epub Aug 12, 2010]

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New Findings on Nutrients & Mental Function

Diet, Exercise Help Preserve Brain Function

Cognition refers to our ability to process, retrieve and apply information. Cognitive skills are those that people use every day such as memory, learning, reasoning, and decision-making. Though a gradual decline in cognitive function occurs naturally as we grow older, evidence indicates that staying physically active and getting a good supply of essential nutrients are both critical factors in staying mentally sharp.

Studies, for example, have shown that older adults who maintain their level of physical activity with age can slow down their rate of cognitive decline, and that low blood levels of vitamins B12 and folic acid can compromise brain function. Now, preliminary findings from several new studies suggest a potential role for omega-3 fatty acids, vitamin D and flavonoids in helping to counter age-related cognitive impairment.

Omega-3 Boosts Memory for Healthy Adults

The results from two studies were presented in July at the Alzheimer's Association 2009 International Conference in Vienna. One of the studies, which examined the effects of the omega-3 fatty acid DHA in healthy older people with age-related memory complaints, reported improved memory function and heart health.

Nearly 500 people took part in this double-blind, 6 month, multi-site trial. Compared to those receiving a placebo, participants taking supplemental DHA had almost double the reduction in errors on a test that measures learning and memory performance (1). In addition, the researchers noted a decrease in heart rate in the DHA group, while blood pressure and weight did not change.

In contrast to the improvements observed in healthy older individuals, a second study presented at the Conference found that DHA did not benefit mental function in patients with Alzheimer's compared to those getting a placebo (2). The investigators did, however, observe a slower rate of decline on a sub-group of people who carried a gene (the e4 version of ApoE gene) that increases the risk of developing Alzheimer's but doesn't affect progression of the disease. Though more research is needed, it may be that nutritional interventions must occur very early in the disease to make any real difference.

Vitamin D & Mental Function in Older Men

Several recent studies have linked low blood levels of vitamin D with reduced cognitive abilities in older adults. Newly reported results from the European Male Aging Study are in agreement with these previous findings (3). In this study, over 3000 men age 40-79 underwent evaluation of their cognitive skills and vitamin D status.

Lower blood concentrations of vitamin D were associated with poorer performance on a test that measures how fast information is processed and visual short-term memory. This observation underscores the need for health professionals to routinely test blood levels of vitamin D, especially in older people.

Wine, Chocolate & Tea for Better Cognition?

Foods like fruits, wine, tea and chocolate are high in polyphenols, particularly flavonoid compounds. Intakes of flavonoids have been linked to a lower risk for age-related cognitive decline and dementia. In a newly published study (4), about 2000 men and women took a battery of tests evaluating learning, memory, attention, and verbal fluency. Their intake of wine, chocolate and tea was also determined.

Performance on the cognitive tests was higher in people consuming up to 10 grams per day of chocolate (typically less than of a chocolate bar) and 2-3 ounces of wine, with the effects stronger for wine consumption. Importantly, the effects were most pronounced for people consuming all three foods.

References

1. Yurko-Mauro K, et al. Results of the MIDAS Trial: Effects of docosahexaenoic acid on physiological and safety parameters in age-related cognitive decline. Alzheimer's Assoc 2009 Inter Conf Presentation #01-04-01, July 2009.
2. Quinn JF, et al. A clinical trial of docosahexaenoic acid for the treatment of Alzheimer's disease. Assoc 2009 Inter Conf Presentation #01-04-02, July 2009.
3. Lee DM, et al. Association between 25-hydroxyvitamin D levels and cognitive performance in middle-aged and older European men. J Neurol Neurosurg Psychiatry 80:722-9, 2009.
4. Nurk E, et al. Intake of flavonoid-rich wine, tea, and chocolate by elderly men and women is association with better cognitive test performance. J Nutr 139:120-7, 2009.

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In the News: Omega-3s, Antioxidants and GLA

Omega-3s, Zinc & "C" May Ease Asthma

Results of new research suggest that a combination of fish oil, zinc and vitamin C can improve the symptoms of bronchial asthma in children (1). Asthma, which affects nearly 20 million Americans, is on the rise according to the American Lung Association.

In this double-blind study, 60 asthmatic children were supplemented with 300 mg of EPA and DHA, 15 mg of zinc, 200 mg of ascorbic acid, a combination of all the nutrients or a placebo for 6 week periods. Lung function was measured, as were markers of inflammation. Symptoms such as wheezing, shortness of breath and the use of rescue inhalers were measured in a standardized test.

The researchers found significant improvement in all the tests when the nutrients were given one at a time. However all three nutrients combined produced the best results.

Omega-3s & Better Blood Pressure in Dieters

One of the many benefits of weight loss is often blood pressure reduction, and results of a recent study suggest that the omega-3s can result in even better reductions - at least in those who have low levels of the omega-3 DHA stored in their cell membranes (2). Low levels of cellular omega-3 are believed to reflect infrequent intake of these important fatty acids.

All of the 324 overweight study participants, aged 20-40, were put on weight loss diets and divided into 4 different groups. One group ate salmon 3 times weekly, while another consumed cod, which is lower in omega-3 content. The third group was given supplements providing about 495 mg of EPA and DHA daily, while the forth group was assigned to a placebo and ate no seafood.

All of the study subjects lost weight - a little over 11 pounds on average. Blood pressure also went down overall, but reductions were greater in those eating salmon or receiving the daily omega-3 supplement compared to people in the cod-consuming group and in placebo-takers who had low stores of the omega-3 to begin with. These observations are in line with a number of other study findings that indicate blood pressure reductions with greater EPA and DHA intake.

GLA Makes Contact Wear More Comfortable

Contact lens wearers commonly experience a feeling of dryness in their eyes. As a result, many people wear their lenses less often or discontinue their use altogether. A recent double-blind, placebo-controlled study examined the effects of 300 mg of supplemental GLA daily in 76 women with contact lens-related dry eye (3). The participants all wore soft contact lens.

The women in the GLA group experienced significant improvement in the sensation of dryness and overall lens comfort at 3 months and at 6 months, when the study ended. Tear meniscus height - a relatively new measurement of tear production - was also greater in the GLA supplementers compared to placebo.

Antioxidants, Exercise Boost Bones in Women

The results of a pilot study in 34 post-menopausal women suggest that a combination of antioxidant supplements and resistance training may help protect against bone loss. The women were assigned to 1 of 4 groups: 1) antioxidants plus exercise; 2) antioxidants and no exercise; 3) placebo plus exercise; or 4) placebo and no exercise. The antioxidants consisted of 600 IU vitamin E and 1,000 mg of vitamin C daily.

At the end of 6 months, measures of bone density revealed that only those women not exercising and getting the placebo experienced significant bone loss in the spine. In contrast, the bone density of those who exercised or took the antioxidants remained constant. These preliminary findings are promising and lend support to previous links seen between higher intake of antioxidants (e.g. lycopene) and better bone density in the spine of women and, for men, in the hip.

References

1. Al Biltagi M, et al. Omega-3 fatty acids, vitamin C and zinc supplementation in asthmatic children: a randomized, self-controlled study. Acta Pediatrica 98:737-42, 2009.
2. Ramel A, et al. Moderate consumption of fatty fish reduces diastolic blood pressure in overweight and obese European young adults during energy restriction. Nutrition [Epub May 30, 2009].
3. Kokke KH, et al. Oral omega-6 essential fatty acid treatment in contract lens association dry eye. Contact Lens Anterior Eye 31:141-6, 2008.
4. Chuin A, et al. Effect of combined antioxidants compared to resistance training on BMD in elderly women: a pilot study. Osteoporosis Inter 20:1253-8, 2009.

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Drink to your Health: Red Wine and Pomegranate Juice

Red Wine and Heart Health

The potential health benefits of wine received wide- spread attention in 1991, when 60 minutes reported on the "French Paradox" - an observation that the French enjoy one of the lowest heart attack rates, despite their penchant for eating lots of saturated fats. While more recent statistics suggest that heart disease in France may have been underestimated in those years, support for alcohol and red wine's apparent heart-healthy role has grown. We're also learning more about how the individual components in wine may contribute to its overall effects.

The Rise of Polyphenols and Resveratrol

The most abundant antioxidants in our diets aren't the ones we're most familiar with, according to Dutch researchers (1). The most plentiful are compounds called polyphenols. About 6000 different flavonoid polyphenols are known, and we may consume as much as a gram of them daily. In contrast, intake of vitamins C, E and beta-carotene combined often amounts to less than 100 mg a day. It is increasingly clear that polyphenols are major contributors to the antioxidant actions of fruits and vegetables.

Wine contains an array of polyphenols, including flavonoids, primarily from the skins of the grapes (which are removed in making white wine). Studies generally show a positive link between dietary flavonoid intake and good health overall, and with cardiovascular health especially (2).

A recently published study (3) suggests that enjoying a glass of wine with fish (both featured in the Mediterranean diet) might maximize omega-3s and explain one way that wine reduces heart disease risk. Moderate wine consumption - 1 glass a day for women, 2 daily for men - was found to boost levels of omega-3 in cell membranes. Because wine had a stronger link with omega-3s than other alcoholic drinks, the scientists think that the polyphenols are key, possibly protecting EPA and DHA from oxidation or stimulating the body to produce more of them.

Trans-resveratrol is another intriguing polyphenol found in grape skins, red wines, and grape juice. In plants, resveratrol acts like an antibiotic, defending the grapevine from disease. Investigators are interested in resveratrol's antioxidant and other properties, as evidenced by its reference in over 2,000 research citations in the National Library of Medicine, including studies at the National Cancer Institute and the National Institute of Aging. One theory holds that polyphenols like resveratrol can help protect the aging brain (4). Another hypothesis is that resveratrol could influence the aging process itself and lead to longer life. Both of these theories need to be confirmed.

Studies have shown that restricting calories increases the lifespan of various animals. It's not clear whether this might hold true in humans where longevity is determined by complex mechanisms, but interest in resveratrol surged when it was found to trigger effects in animals like those prompted by calorie restriction (5).

The Growing Promise of Pomegranates

Pomegranate juice is also chocked full of polyphenols with the capacity to mop up free radicals and interfere with chronic inflammation. This juice, in fact, contains more polyphenols than blueberries, cranberries, green tea, orange juice or even red wine.

Most of the clinical studies exploring the effects of pomegranate juice have been small, but with promising results that warrant further investigation (6,7). Drinking about 2 ounces daily for a year has been shown to reduce the intimal-media thickness of the carotid artery - a measurement of artery walls that's used to track the progression of atherosclerotic disease. In another study, daily intake of about 8 ounces is reported to decrease stress-induced ischemia in patients with heart disease compared to a placebo. It may be that pomegranate polyphenols help protect blood vessels or influence inflammation in artery walls.

References

1. Geleijnse JM, et al. Flavonoids and cardiovascular health: which compounds, what mechanisms? Am J Clin Nutr 88:12, 2008.
2. Erdman JW, et al. Flavonoids and heart health: proceedings of the ILSI North America Flavonoids Workshop, 2005, Washington, DC. J Nutr 137(3 Suppl 1):718S-37S, 2007.
3. de Giuseppe R, et al. Alcohol consumption and n-3 poly-unsaturated fatty acids in healthy men and women from 3 European populations. Am J of Clin Nutr 89:354-62, 2009.
4. Vingtdeux V et, al. Therapeutic potential of resveratrol in Alzheimer's disease. BMC Neurosci 9 Suppl 2:S6, 2008.
5. Barger JL, et al. A low dose of dietary resveratrol partially mimics caloric restriction and retards aging parameters in mice.
6. Basu A, et al. Review, Emerging Science. Pomegranate juice: A heart-healthy fruit juice. Nutr Rev 67:49-56, 2009.
7. Jurenka JS. Review: Therapeutic applications of pomegranate. Altern Med Rev 13:128-44, 2008.

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Four New Studies Underscore Vital Role of Vitamins & Minerals

Latest Findings are Encouraging

Four new studies reinforce previous findings for some essential nutrients, while suggesting potential new benefits for others. Calcium, vitamin D and three of the B-vitamins are featured in a quartet of studies published in the Archives of Internal Medicine.

The Calcium and Cancer Connection

Some previous population-health studies have found a link between calcium intake and cancer, but the evidence has been inconsistent. The calcium-cancer relationship appears to be affirmed in the large National Institutes of Health AARP Diet and Health Study which followed nearly 294,000 men and 199,000 women aged 50-71 for seven years (1).

Women consuming up to 1,300 mg of calcium daily from foods and supplements had a decreased risk of any type of cancer. A 23% lower risk for digestive types of cancer, particularly colorectal cancer, was seen for those women in the top 20% of calcium intake compared to those consuming the least. The highest consumers among men also had a 16% lower risk of cancer in the digestive cancer category.

Higher Vitamin D for Fewer Broken Bones

Though calcium may prove important in cancer prevention, the results of another study suggest that calcium may play second fiddle to higher levels of vitamin D when it comes to protecting bones. Harvard researchers performed a meta-analysis (review) of 12 clinical trials involving vitamin D supplements in over 42,000 adults aged 65 or older (2). They found that supplemental vitamin D was associated with a 14% decrease in the risk of non-vertebral fractures and a 9% decrease in the risk of hip fractures. More importantly, when they looked at 9 of the studies using doses over 400 IU per day, the supplements were associated with a 20% and 18% reduction in non-vertebral and hip fractures, respectively. The researchers noted that while calcium was protective, the mineral did not have an additional effect in individuals taking high doses of vitamin D.

Risk of Colds Influenced by Vitamin D?

vitamin D deficiency has resurfaced in recent years, resulting in diseases such as rickets in children. vitamin D research has also exploded, with better blood levels of vitamin D now linked to lower incidences of cancer, multiple sclerosis and heart disease. Another line of inquiry under hot pursuit is vitamin D's role in the immune system.

In an analysis of the 3rd National Health and Nutrition Examination Survey (3), researchers found that people with low blood levels of this vitamin were more likely to have an upper respiratory tract infection (URTI) which can include colds, sinusitis, pharyngitis and flu. Compared to people with higher vitamin D blood levels (30 ng/mL or more), those with lower values (under 10 ng/mL) were 36% more likely to have had a recent URTI. People with intermediate values (10-29 ng/mL) had 24% higher odds. Whether getting more vitamin D will actually help prevent URTIs needs to be confirmed in controlled trials.

B-Vitamins Lower AMD Risk in Women

Previous studies have suggested an association between age-related macular degeneration (AMD) and elevated blood levels of homocysteine - a compound that can be lowered by folic acid, B6 and B12. To determine whether B-vitamins might help prevent AMD, about 5,400 female health professionals who already had, or were at high risk for, heart disease were given very high doses of these 3 B's or a placebo (4).

After more than 7 years of follow-up, the women assigned to the supplemental B-vitamin group lowered their risk of developing any AMD by 34%. The risk for visually significant AMD was reduced by a solid 41%. These findings are exciting, and the next step is to test whether lower, more reasonable levels of the B's are just as effective when supplemented over time.

References

1. Park Y, et al. Dairy food, calcium and risk of cancer in the NIH-AARP Diet and Health Study. Arch Int Med 169:391-401, 2009.
2. Bischoff-Ferrari HA, et al. A meta-analysis of randomized controlled trials Prevention of non-vertebral fractures with vitamin D and dose dependency. Arch Int Med 169:551-61, 2009.
3. Ginde A, et al. Association between serum 25-hydroxyvitamin D level and upper respiratory tract infection the Third National Health and Nutrition Examination Survey. Arch Int Med 169:484-90, 2009.
4. Christen W, et al. Folic acid, pyridoxine, cyanocobalamin combination treatment and age-related macular degeneration in women. Arch Int Med 169:335-4, 2009.

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Diabetes & Nutrition Part I: New Dietary Findings

Weight is Key to Fending off Type 2 Diabetes

A trio of studies published late last year in the journal Archives of Internal Medicine shed new light on the importance of diet in risk of developing type 2 diabetes - especially the role of calories. The bottom line from all three studies is that calories trump all else, and that our main goal in preventing type 2 should be to eat less high-calorie, low-benefit foods.

Fruit Drinks are Culprits; Fruits & Veggies Help

In the first study (1), which followed nearly 44,000 Afro-American women for 10 years, the risk of developing type 2 was 24% higher for those who consumed two or more soft drinks daily compared with women who drank them rarely. Sipping fruit drinks was even riskier, with a 31% increased risk for those drinking them twice daily.

Diet soft drinks as well as grapefruit and orange juice did not up the risk for diabetes. Unlike other fruit drinks, these juices contain mostly naturally occurring sugars which may have different metabolic effects than the high-fructose corn syrup used to sweeten other juice drinks.

In the second study(2), blood levels of vitamin C (an indicator of fruit and vegetable intake) and fruit and veggie consumption were measured in about 22,000 people without diabetes. After a dozen years, those with the highest vitamin C levels were 62% less likely to develop the disease. A similar but smaller risk reduction of 22% was observed for those eating even modest amounts of fruits and veggies.

In the last study(3), 60% of the nearly 49,000 women participants continued with their regular diet while 40% were assigned to a low fat diet with added fruits, veggies and grains. Although the diet was not designed for weight loss, those in the low-fat diet group lost about 5 pounds more over an 8 year period compared to the "usual diet" group. The researchers concluded that losing weight - rather than eating less fat - was more important in preventing type 2.

For Diabetics, Recommended Diet May Need Changing

...or so suggests a new study(4) that is one of the longest and largest to assess the impact of foods with a low glycemic index (GI). Low GI foods don't raise blood sugar as much as foods with a higher GI.

People with type 2 were assigned to one of two diets. The first emphasized "brown foods" such as whole grain bread and breakfast cereal, brown rice and potatoes with the skin on. This high fiber, high cereal diet is what is usually recommended for those with diabetes.

The other diet focused on low GI foods which included beans, peas, lentils, pasta, quickly boiled rice and certain breads like pumpernickel and rye, as well as oatmeal and oat bran cereals.

Both diets were low in saturated and trans fats. Both groups were told to limit their consumption of white flour and to eat five servings of vegetables and three servings of fruit daily.

At the end of six months, people on the low GI diet kept their blood sugar under better control and had slight reductions in HA1C levels - a measure of blood sugar levels over time. They also experienced significant increases in "good" HDL cholesterol, which is good for heart health. That's important because diabetic men have twice the risk for heart disease and women four times the risk. Also, drugs used to control type 2 have not shown the expected benefits in terms of reducing heart disease.

The bottom line is that high fiber foods are fine, but include beans and nuts and try to eat more low GI foods

References

1. Palmer JR, et al. Sugar-Sweetened Beverages and Incidence of Type 2 Diabetes Mellitus in African American Women. Arch Int Med 168:1487-92, 2008.
2. Harding A-H, et al. Plasma Vitamin C Level, Fruit and Vegetable Consumption, and the Risk of New-Onset Type 2 Diabetes Mellitus: The European Prospective Investigation of Cancer-Norfolk Prospective Study. Arch Int Med 168:1493-99, 2008.
3. Tinker LF, et al. Low-Fat Dietary Pattern and Risk of Treated Diabetes Mellitus in Postmenopausal Women: The Women's Health Initiative Randomized Controlled Dietary Modification Trial. Arch Int Med 168:1500-11, 2008.
4. Jenkins DJ, et al. Effect of a low-glycemic index or a high-cereal fiber diet on type 2 diabetes: a randomized trial. JAMA 300:2742-53, 2008.

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News Bites: Recent Research Findings for Men

Men's Interest in Nutrition Increasing

Several years ago, a Men's Nutrition Survey reported that now more than ever, men are interested in nutrition for health. Of those surveyed, 42% said health maintenance and disease prevention were the most important reasons for eating right. Heart disease, certain cancers, stroke and diabetes are all linked to diet, and several of these diseases tend to hit men in their early 40s. Scientists are also reporting that pre-conceptual nutrition is important for men, so it's never too early to make healthy dietary changes. Recent research, for example, suggests that eating more whole grains and green leafy vegetables - a good source of magnesium and folic acid - is a great idea, as is consuming more colorful fruits and veggies for their healthful carotenoid content.

Folic acid and Healthy Sperm

Folic acid's role in reducing the risk of neural tube defects in infants has made this an important nutrient for women in their childbearing years. Now, the authors of a new study believe their findings are the first to indicate that folic acid could be equally important to fertility in men (1).

Researchers determined the total intake of the nutrients zinc, folate, vitamin C, vitamin E and beta-carotene from food sources and from dietary supplements for healthy, non-smoking men. They then investigated the subjects' rate of aneuploidy. Aneuploidy is a term that refers to the changes in the number of chromosomes. Aneuploidy is linked to infertility and miscarriages as well as Down's syndrome. Between 1-4 % of a healthy man's sperm is thought to have some form of aneuploidy.

Men who had the highest folate intake (between 772 and 1,150 micrograms daily) had 20-30% lower sperm aneuploidy than those who consumed the least. Men who ate the most zinc and beta-carotene also had fewer instances of some sperm abnormalities, but not aneuploidy. It's known that diets low in zinc can reduce sperm counts, while excessive alcohol can reduce zinc levels even further. Keep in mind that this study does not prove that high folate intake causes the enhanced sperm quality, only that there was an association. But the relationship between folic acid and fertility is plausible and warrants further study in controlled trials.

More Magnesium for Fewer Strokes

Sodium, potassium, calcium and magnesium have all been linked to blood pressure. Researchers set out to examine the link between these minerals and the risk of stroke in male smokers. Following over 29,000 men for 13 ½ years, they found that only magnesium lowered the risk of ischemic stroke, and that the risk reduction was more pronounced in men under 60 (2). Ischemic stroke is the most common kind of stroke, and it occurs when an artery to the brain is blocked. Magnesium did not seem to influence the risk for the less common type of stroke, hemorrhagic.

The relationship between magnesium and stroke makes good biologic sense according to the authors. In addition to lowering blood pressure, magnesium can influence cholesterol concentration or the body's use of insulin to turn glucose into energy. "Either of these mechanisms would affect the risk for ischemic but not hemorrhagic stroke. These findings are important because dietary surveys show that a large portion of adults do not meet the RDA for magnesium.

Lycopene and Benign Prostate Hypertrophy (BPH)

Some, though not all, population health studies have reported a lower risk for BPH or prostate cancer with higher intake of lycopene, the carotenoid concentrated in tomatoes. Results of a new pilot study report that supplementation with lycopene slowed progression of BPH. Elderly men diagnosed with BPH were given 15 mg of lycopene or placebo daily for 6 months. Those receiving lycopene had a significant reduction of serum prostate-specific antigen (PSA) levels and no further enlargement of the prostate as assessed by trans-rectal ultra-sonography and digital rectal exam. In contrast, placebo takers had no change in PSA while the prostate continued to enlarge (3).

References

1. Young SS, et al. The association of folate, zinc and antioxidant intake with sperm aneuploidy in healthy non-smoking men. Human Reprod Epub Mar 19, 2008.
2. Larsson S, et al. Magnesium, calcium, potassium and sodium intakes and risk of stroke in male smokers. Arch Int Med 168:459-65, 2008.
3. Schwarz S, et al. Lycopene inhibits disease progression in patients with benign prostate hyperplasia. J Nutr 1308:49-53, 2008.

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