Millions of people daily pop in antioxidant vitamins considering that it would increase their life span but according to analysis of various studies, evidence has been found regarding the authenticity of these popular supplements. The review of certain studies on thousands of people found no long-life benefit from vitamins A, E and C and beta carotene and selenium. However some studies support the theory that antioxidants work best when they are consumed in food rather than pills. The Cochrane organization in Denmark conducted a research in which after eliminating the lower-quality studies and looked only at the most trustworthy ones, they found a higher risk of death for people taking vitamins: 4 percent for those taking vitamin E, 7 percent for beta carotene and 16 percent for vitamin A. The study's senior author, Dr. Christian Gluud said, "The main message is that prevention by beta carotene, vitamin A and vitamin E cannot be recommended. These three antioxidant supplements may increase mortality." But some researchers now believe antioxidants work only when they are in food, or that people who eat vitamin-rich food are healthier simply because they take better care of themselves. And beta carotene supplements have been found to increase lung cancer risk in smokers.

An estimated 80 million to 160 million people take antioxidants in North America and Europe, about 10 to 20 percent of adults, the study's authors said. And last year, Americans spent $2.3 billion on nutritional supplements and vitamins at grocery stores, drug stores and retail outlets.
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