Better to Get Nutrient From Food Than Supplements
But don't try taking a shortcut by taking vitamin E supplements instead. A new study shows that supplements simply don't provide the same protective effect as the real thing from natural sources, such as walnuts, pecans, sesame seeds, wheat germ, spinach, and other dark, green leafy vegetables.
Researchers reviewed current research on the effects of vitamin C, vitamin E, and beta-carotene on the risk of developing Parkinson's disease and found that only vitamin E eaten in its natural form appears to have a significant impact in reducing the risk of Parkinson's.
But before you reach for the walnuts, researchers say further study is needed to confirm vitamin E's potentially anti-Parkinson's effects before doctors can start recommending dietary changes in hopes of preventing the disease in people at risk.
Parkinson's disease is a progressive neurological disease that causes the loss of muscle control. Although the exact cause is unknown, Parkinson's disease is thought to be the result of a combination of risk factors, such as aging, a family history of the disease, and various environmental factors, including diet.
Vitamin E May Protect Brain
In the study, researchers reviewed studies on vitamin C, vitamin E, and beta-carotene and Parkinson's disease risk published between 1996 and March 2005. The results appear in the May 19 online edition of Lancet Neurology.
Overall, seven studies showed that diets that contained a moderate amount of vitamin E reduced the risk of developing Parkinson's disease by 19%.
Moderate vitamin E diets were those that fell in the middle range of intake of the vitamin in each of the studies included. According to the federal government, the recommended dietary allowance (RDA) for vitamin E is 15 milligrams of the alpha-tocopherol form of vitamin E. Alpha-tocopherol is the form of the vitamin that the body uses.
Although eating larger amounts of vitamin E appeared to further reduce Parkinson's risk, researchers say too few studies contained data on this to draw any firm conclusions.
But seven studies on vitamin C and four on beta-carotene did not indicate that diets rich in these nutrients had a protective effect against Parkinson's disease.
The American Dietetic Association gives the following examples of how much vitamin E is in a variety of foods:
- 24 almonds. About a handful has 7.4 milligrams
- Hazelnuts. 20 nuts has 4.3 grams
- Broccoli. 1 cup cooked has 2.9 milligrams
- Wheat germ. 1 tablespoon has 1.3 milligrams
- Avocado. 1 ounce has 0.4 milligrams