In the News: B12 & the Brain, Omega-3 & Broccoli for Ailing Hearts
B12 May Help Retain Brain Volume with Age
Maintaining optimal blood levels of vitamin B12 is important, as low levels appear to increase the risk for impaired mental function and neurological disorders. A new study now indicates that failure to get enough B12, or absorb it well, may actually cause the brain to shrink.
The participants in this study, who had an average age of 73 with no mental impairments at the beginning, were divided into 3 groups based on their B12 levels. They underwent MRI scans to measure brain volume and physical and mental exams annually. At the end of the 5-year study period, the group with the lowest B12 levels (below 308 pico-moles/L) lost twice as much brain volume as those with the highest levels. The same researchers are now conducting a study to see whether improving B12 levels will actually prevent brain shrinkage.
It's estimated that up to 25% of the elderly may be B12 deficient. Poor dietary intake or absorption of this vitamin, found only in foods of animal origin including meat, milk, eggs, as well as some fortified cereals, is usually the problem. Most commonly, the age-related decline in stomach acid makes it difficult to digest B12. In addition, some people don't make enough of a small protein called intrinsic factor, which is needed for efficient B12 absorption. The Institute of Medicine recommends supplemental B12 for those over 50, and those with a lack of intrinsic factor often need medical intervention.
Fish Oil Helps Survival Rates in Heart Failure
According to new research, a daily supplement of fish oil omega-3 reduced mortality and cardiovascular-related hospital admissions for patients with heart failure, while statin drugs had no beneficial effect in the same group of patients.
Years ago, a group of Italian researchers (the GISSI) documented the preventive benefits of fish oil in those who had a heart attack by reducing their subsequent risk of sudden death. This same research group has recently published the results of the first large-scale double blind trial investigating the effectiveness of fish oil in chronic heart failure.
In the first trial, 6,975 patients with symptomatic heart failure were randomized to receive either 1 gram daily of omega-3 (EPA and DHA in ethyl ester form) or placebo. After nearly 4 years of follow-up, the risk of mortality was reduced by 9% and hospitalization for cardiovascular causes decreased by 8%.
In contrast, chronic heart failure patients assigned to get 10 mg of a statin drug (rosuvastatin) fared no better in terms of survival or hospitalization rates than those getting placebo. Even though the statin lowered LDL cholesterol and the inflammation marker CRP, the investigators theorize that once heart failure is established, statins may not allow patients to escape the underlying heart-disease process.
Broccoli May Reverse Heart Vessel Damage
Researchers report that compounds such as sulforaphane in broccoli may help counter processes thought to lead to vascular disease in diabetes. The investigators concluded that sulforaphane may function as a "dietary activator", preventing dysfunctional responses of endothelial cells that line the interior of blood vessels caused by elevated blood sugar. Endothelial cell dysfunction is common in diabetics.
The research team found a 73% in reduction in free radicals, which are known to increase in diabetics. While this study was conducted in cultured human endothelial cells, it may help explain why large-scale studies have linked high intake of broccoli, Brussels sprouts and cabbage to a lower risk of developing diabetes.
- Vogiatzoglou A, et al. Vitamin B12 status and rate of brain volume loss in community-dwelling elderly. Neurology 71:826-32, 2008.
- GISSI-HF Investigators. Effect of n-3 poly-unsaturated fatty acids in patients with chronic heart failure: a randomized, double-blind controlled trial. Lancet Aug. 29, 2008 [epub ahead of print].
- GISSI-HF Investigators. Effect of rosuvastatin in patients with chronic heart failure: a randomized, double-blind placebo-controlled trial. The Lancet 372:1231-9, 2008.
- Xue M, et al. Activation of NF-E2-related factor-2 reverses biochemical dysfunction of endothelial cells induced by hyperglycemia linked to vascular disease. Diabetes 57:2809-17, 2008.