ANTIOXIDANTS. Antioxidants are specific organic compounds that are active in the prevention of very rapid harmful chemical chain reactions with oxygen or nitric oxide, that is, oxidation reactions. In the body, oxidation reactions generally involve highly reactive molecules called free radicals. Free radicals reside primarily in the mitochondria of cells. When free radicals are released from the mitochondria in numbers sufficient to overwhelm the protective biochemical systems of the body, they become a threat to some cellular structures such as lipids, proteins, carbohydrates, and nucleic acids in cell membranes. Compromised cellular structure alters cellular function, and may lead to the initiation of the disease process. In severe oxidative stress, cell death may occur. Antioxidants react with the free radicals before they are able to react with other molecules, thus providing protection from oxidation reactions (Cross et...