At the molecular and cellular levels, antioxidants serve to deactivate certain particles called free radicals. In humans, free radicals usually come in the form of O2, the oxygen molecule. The oxygen molecule wants to be oxidized, and this oxidation process can sometimes be carcinogenic. Free radicals are the natural by-products of many processes within and among cells. They are also created by exposure to various environmental factors, tobacco smoke and radiation, for instance.

Anti Oxidants contribute to the oxidation of free radicals, which are believed to contribute to premature ageing and dementia. Anti Oxidants also protect the eyes, cardiovascular system and central nervous system.