Vitamins and antioxidants are good for you, right? Well, in the latest issue of The Cochrane Library, a group of scientists in Denmark reviewed almost 70 studies on the effects of vitamin or antioxidant supplements and found no evidence that they help you live longer. They even found evidence that beta-carotene, Vitamin A, and Vitamin E supplements may actually shorten your life.

After statistically analyzing data gathered from 67 randomized studies including over 200,000 participants, the scientists found that Vitamin A supplements increased the risk of death in healthy individuals by 16%. Vitamin E was associated with a 7% increased risk, and beta carotene increased by risk of death by 4%. Although Vitamin C supplements were not associated with higher mortality, they were also not shown to prevent disease.

Fruits and vegetables are the main sources of dietary antioxidants, but many people use supplements because they do not eat enough for their daily requirement. Theoretically, antioxidants overcome the damaging effect of oxygen on cells by neutralizing the effect of harmful free radicals. However, it is not known whether antioxidants taken in pill form, rather than as part of a healthy, balanced diet, are processed in the same way by the body. The reviewers of this study suggested that antioxidant supplements might interfere with the body's natural immunity.

So, for now, there is no magic pill, and, for healthy people, supplementation hasn't been proven to be better than a balanced diet.