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Which Vitamin Boosts Brain Power
Vitamin E has been touted for its anti-aging and anti-cancer benefits because, as an antioxidant, it counters the destructive action of molecules called free radicals. Now a study has shown vitamin E may also help the memory loss and impaired thinking that occurs in the elderly.
Researchers at the Rush Institute for Healthy Aging in Chicago conducted a three-year study involving nearly 3,000 people older than 65 to investigate the cognitive effects of vitamin E in food and supplements.
By comparing the average scores of four different tests of memory and perception, the researchers were able to track change in cognitive function with age. The participants also completed dietary questionnaires periodically, which enabled the researchers to determine their vitamin E intake.
The study found that the higher the intake of total vitamin E, the less change there was in the people’s average test scores each year. And those men and women who consumed the most vitamin E had a 36 percent lower rate of decline in their average test scores than those who consumed the least vitamin E. Other antioxidants, such as vitamin A, carotene and vitamin C, had little effect on the results.
Those who took supplements but got little vitamin E from food appeared to have the same protective benefit from the vitamin as those who consumed high amounts of E in their diets, says Martha Clare Morris, an assistant professor at Rush-Presbyterian-St. Luke’s Medical Center. Several clinical trials are underway to compare protection from cognitive decline in people taking a supplement or a placebo, she says. In this study, the majority who took a supplement reported taking 400 IU a day.
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