Lutein and AMD: Results from CAREDS
The CAREDS Study
A number of studies have looked at the relationship between dietary lutein and zeaxanthin intake and the risk for age-related macular degeneration (AMD). Many - though not all - of the findings from these population health studies suggest that eating more lutein-rich foods is beneficial.
The authors of the Carotenoids in Age-Related Eye Disease Study (CAREDS) now report that a stable intake of these nutrients over time could reduce the risk of AMD by 43% in healthy women under 75.
CAREDS, an off shoot of the Women's Health Initiative (WHI), looked at over 1780 women aged 50-79 who had either high or low intake of lutein plus zeaxanthin when they entered the WHI study. These women were later asked to participate in CAREDS, and researchers determined which of them had developed AMD using special photographic techniques.
Regular Lutein Intake Supports Visual Health
Women with higher intakes of lutein plus zeaxanthin (at least about 3 milligrams or more daily) had a substantial 43% lower risk for intermediate AMD compared to those eating about � of a milligram or less every day. This protective effect was seen in women 75 years and younger who had stable intakes of these nutrients.
Safely Achieving a Lutein-Rich Diet
If a higher and consistent intake of lutein and zeaxanthin is important, how do we go about achieving it?
A commonly eaten, concentrated source of lutein is green leafy vegetables such as spinach. Some people are leery of eating fresh spinach because of the recent contamination of certain fresh spinach brands with the illness-causing, bad bug E. coli 0157:H7. Information about the brands and batches that were recalled can be found at the Center for Food Safety and Applied Nutrition (CFSAN) (http://www.cfsan.fda.gov/list.html).
According to CFSAN, no frozen or canned spinach was implicated in this most recent outbreak.
Should an E. coli 157:H7- related outbreak occur in the future, CFSAN indicates that cooking fresh spinach at 160 degrees Fahrenheit for at least 15 seconds will kill any E. coli O157:H7 present.
Eat a Variety of Lutein-Containing Foods
While terrific, spinach isn't the only source of lutein and zeaxanthin. These nutrients can also be obtained from eating corn, broccoli, peas, squash and other green leafy vegetables like kale, collards and mustard greens. Consuming a wide variety of produce is healthful overall, and the CFSAN website offers a handy booklet of general safety tips for storing and preparing fresh produce and juices called Safe Handling.
Eggs yolks are another excellent source. Though they contain considerably less of these nutrients than spinach, the lutein and zeaxanthin they do contain is very well absorbed according to several recent studies. The good bioavailability is likely due to the fats found in egg yolk. Lutein and zeaxanthin are fat-soluble, so absorption is enhanced when fat is present. While eggs contain 213 mg of cholesterol - and the recommended intake of dietary cholesterol is 300 mg. daily - eggs can fit into the daily cholesterol budget several times weekly if you limit cholesterol from other sources such as meats, poultry and dairy products.
Lutein Supplements Can Also Play a Role
While the ideal intake of lutein has not been pinned down, we do know that the typical American intake of 1-2 mg daily from foods falls short of the 3-7 mg daily that studies suggest may be beneficial. Supplements of lutein and zeaxanthin can also be of help in closing this dietary gap and ensuring regular intake.
Moeller SM et al. Age-Related Macular Degeneration
and Lutein and Zeaxanthin in the Carotenoids in Age-Related Eye Disease Study (CAREDS). Archives of Ophthalmology 124:1151-1162, 2006