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kaniamazdar
In 1956, Denham Harman at the University of Nebraska proposed that antioxidants would prolong life. He explained that the human body converts food to energy by stripping off electrons and protons from food in a series of chemical reactions that leaves extra electrons to attach to oxygen. Most of the charged oxygen combines with hydrogen to form water, but some sticks to the DNA in cells to damage them and shorten life. He proposed that antioxidants would prevent this and thus prolong life. A recent review of the world's scientific literature shows that he may be wrong. Researchers from Copenhagen University Hospital in Denmark analyzed 68 studies involving 230,000 participants taking antioxidant supplements and found that beta carotene and vitamins A and E, given singly or combined with other antioxidants, shortened the lives of those who took them (JAMA , February 2007).
Current research shows only four possible ways to extend maximum lifespan: exercise, calorie restriction with adequate nutrition, and two chemicals: resveratrol and dichloroacetate (in experimental use only). All these enhance the mitochondria in cells so that they produce far fewer oxidants. None have been shown to extend life by increasing antioxidant production. Mitochondria are the furnaces in cells that turn food into energy. By increasing the size and number of mitochondria, these four factors make the engines far more efficient so that they burn fuel cleaner to produce far less reactive oxygen species. None have been shown to increase antioxidant production.
Taking large doses of antioxidants, such as the vitamins; beta carotene and vitamins A, C and E, produces high tissue levels of these vitamins that the body couldn't possibly be exposed to from food. This could interfere with normal chemical reactions and shorten your life. At this time nobody really knows whether taking antioxidant supplements prolongs or shortens life. More
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