Nutrients such as vitamin C, vitamin E, and zinc have antioxidant effects and may be able to avert cardiovascular disease and cancer. This makes sense in the abstract, but trials in which people have taken these nutrients for a long time have not found that they help. Researchers in France reported recently on another trial of antioxidants.

What the researchers wanted to know: Does an antioxidant supplement decrease the risk of cancer and cardiovascular disease in middle-aged people?

What they did: Researchers recruited, through the French media, women ages 35 to 60 and men ages 45 to 60; after weeding out more than 67,000 people who were ineligible for one reason or another (like having extreme diet beliefs or being unwilling to take the risk of getting the placebo), 12,741 people were randomly and secretly assigned to take either a placebo or the antioxidant supplement. The supplement had a little bit of everything—120 milligrams of vitamin C, 30 milligrams of vitamin E, six milligrams of beta carotene, 100 micrograms of selenium, and 20 milligrams of zinc. The people came in every few years for blood tests and physical examinations. The researchers kept up with their health and any adverse events, especially ischemic cardiovascular events and cancer.

What they found: After 7.5 years, there was no difference between the antioxidant supplement and the placebo for cancer risk or risk of ischemic cardiovascular disease. But when the researchers broke the data down into men and women, they did see fewer cancers among men taking the antioxidant, so it's possible that it had some preventive effect in men.

What the study means to you: This particular antioxidant supplement might help prevent cancer in men.

Caveats: There have been several trials on antioxidant supplements, and many have found no protective effect. Also, the researchers lost a lot of patients over 7.5 years, and they don't know what happened to them—they could have died of cancer or just gotten tired of taking a mystery pill.

Find out more: Both the American Heart Association and the American Cancer Society recommend getting antioxidants from plant foods, not supplement pills.

Read the article: Hercberg, S., et al. "The SU.VI.MAX Study: A Randomized, Placebo-Controlled Trial of the Health Effects of Antioxidant Vitamins and Minerals." Archives of Internal Medicine. Nov. 22, 2004, Vol. 164, pp. 2335-2342.

Abstract online: http://archinte.ama-assn.org