ABSTRACT
Antioxidants are chemicals that obstruct the action of other chemicals known as free radicals. Free radicals are highly reactive and have the potential to cause damage to cells, including damage that may lead to cancer. Free radicals are produced naturally in the body. Unusually high concentrations of free radicals in the body can be caused by exposure to ionizing radiation and other environmental toxins. The body makes some of the antioxidants it uses to neutralize free radicals, known as endogenous antioxidants. Nevertheless, the body relies on external (exogenous) sources, primarily the diet, to obtain the rest of the antioxidants it needs, known as dietary antioxidants. In laboratory and animal studies, the presence of increased levels of exogenous antioxidants has been shown to prevent the types of free radical damage that have been associated with cancer development.
