Vitamins E and C Called Alzheimer’s Inhibitors

People who eat vitamin E-rich foods like nuts, vegetable oils and leafy vegetables may reduce their risk of developing Alzheimer’s disease by as much as 70%, according to two new studies published to- day .

One of the studies also found that vitamin C-rich foods, such as oranges and tomatoes, can reduce the risk of Alzheimer’s disease.

The studies, published in the Journal of the American Medical Assn., are the first to provide a link between consumption of foods high in antioxidants like vitamins E and C and prevention of Alzheimer’s. Previous studies, which have focused on vitamin intake through nutritional supplements, have produced conflicting results.

Antioxidants have been shown to protect against the effects of so-called “free radicals,” oxygen molecules that can damage brain cells. Researchers think that Alzheimer’s patients have an excess of these toxic free radicals.

The first study, conducted at the Rush Institute for Healthy Aging in Chicago, followed several hundred people over 65 years old for nearly four years. Researchers found that those who consumed the most vitamin E decreased their risk of developing Alzheimer’s by 70% compared to those who ate the least.

People who ate lots of leafy green vegetables, such as kale and collards, often showed the least risk of Alzheimer’s, said lead researcher Martha Morris.

Morris and her colleagues did not see a similar benefit for people taking vitamin E supplements. Morris downplayed the apparent ineffectiveness of vitamin supplements, saying people may not have been taking the supplements long enough. Varying forms of the vitamin in supplements and foods also contribute to the difference, she said.

Other antioxidants and supplements may have a protective effect, “we just don’t know yet,” said Morris. Her group plans to extend the duration of the study to check these possibilities.

A second study, conducted by researchers at Rotterdam’s Erasmus Medical Center in the Netherlands, followed 5,000 people over six years and also showed a similar benefit in eating vitamin E-rich foods. People who most benefited consumed more than 15 milligrams of vitamin E daily.

Bill Thies, vice president of medical and scientific affairs at the Alzheimer’s Assn. in Chicago, said the studies still don’t forge a direct link between vitamin E and Alzheimer’s. Rather they “point a finger in that direction,” he said.

In fact, the two studies conflicted in some respects.

While the Rotterdam study found that foods rich in both vitamins C and E, such as leafy greens, reduced the risk of developing Alzheimer’s, the Chicago study found that vitamin C had no benefits.

The Chicago study also reported that people with a variation of the gene, apolipoprotein E, which is found in many with a family history of Alzheimer’s, did not experience the protective effects of a vitamin E-rich diet. The Rotterdam study found that those with the gene seemed to experience the same protective effects of antioxidants.

Morris and Thies both emphasized that the only way to prove a relationship between antioxidants and Alzheimer’s would be to conduct controlled clinical trials, in which half the participants take vitamin E or eat foods high in vitamin E content, while the other half take a placebo.