Antioxidants are chemicals that block the activity of other chemicals known as free radicals, which are formed naturally in the body. Free radicals are highly reactive and have the potential to cause damage to cells, including damage that may lead to cancer. Cells may function poorly or die if this occurs.

    To prevent free radical damage the body has a defence system of antioxidants. Antioxidants are molecules which can safely interact with free radicals and terminate the chain reaction before vital molecules are damaged.

   An antioxidant is a molecule that inhibits the oxidation of other molecules. Oxidation is a chemical reaction that can produce free radicals, leading to chain reactions that may damage cells. Antioxidants such as thiols or ascorbic acid (vitamin C) terminate these chain reactions.

   Antioxidants are classified into two broad divisions, depending on whether they are soluble in water....