ROTTERDAM, Netherlands—Consumers looking to protect their brain in old age would do well to ensure they’re meeting the RDA for vitamin E, suggests a new study out of The Netherlands. Follow-up work from The Rotterdam Study found adults with baseline consumption of vitamin E in the highest third—around 18 mg/d—had a quarter of the chance of having dementia and/or Alzheimer’s a decade later (Arch Neurol. 2001;67(7):819-25. DOI: 10.1001/archneurol.2010.144).
Researchers from Erasmus Medical Center in Rotterdam, with colleagues from Boston’s Harvard University, originally reported in 2002 that higher dietary intakes of the antioxidant vitamins E and C reduced the risk of dementia and Alzheimer’s over six years of follow up (JAMA. 2002;287(24):3223-9). For their new trial, they took a 10-year look at the protective effect against dementia of consuming antioxidant vitamin E, vitamin C, beta-carotene and flavonoids in the diet.
While no positive association was seen for vitamin C, beta-carotene or flavonoid intake, the subjects with the highest vitamin E dietary intake at baseline had a reduced risk of dementia and Alzheimer’s. Those in the highest tertile of vitamin E intake when the study started had a 24 percent reduced risk of being diagnosed with dementia at study’s end; similarly, that level of consumption yielded a 26 percent reduction in Alzheimer’s risk.
Daniel Fabricant, Ph.D., vice president, global government and scientific affairs, Natural Products Association (NPA), noted the study results should set the stage for future research. “By having the baseline of the previous study, the authors were able to provide population-based estimates of dementia risk over a decade, versus most trials which only are able to capture short term risk in a clinical population,” he noted. “From this they were able to tease out the effect the nutrients had in the long term which per their data held up ten years later, specifically that vitamin E does have a statistically significant effect in reducing risk of dementia.”
The researchers did adjust for subjects who had used supplements—primarily antioxidants—at baseline, but the findings were unchanged. They commented that these findings focused on food-based antioxidants, where levels of consumption were several-fold lower than in many randomized clinical trials (RCTs), many of which have not found an association between vitamin E consumption and dementia. Also, dietary vitamin E delivers all eight forms (alpha-, beta-, gamma- and delta-tocopherols and –tocotrienols), versus the isolated alpha-tocopherol generally used in RCTs.
Fabricant noted the focus on dietary intake was a positive in the study. “The study really accounted for many variables in the diet and how healthy habits may influence the findings of such a study,” he said, “which, if nothing else, shows that given the proper metrics there is support in this study for eating a well-balanced diet with food sources of vitamin E, and that all things considered in looking at diet of such a large population there is a sound argument for use of multivitamins to fill gaps.”
In the Rotterdam cohort, major dietary sources of vitamin E included margarine, sunflower oil, butter, cooking fat, soybean oil and mayonnaise. Nuts, seeds and vegetable oils are the primary contributors of vitamin E in the diet; 1 T of wheat germ oil, for example, supplies 100 percent of the U.S. daily value for vitamin E.