Tocopherols (TCP) are a class of organic chemical compounds (more precisely, various methylated phenols), many of which have vitamin E activity. Because the vitamin activity was first identified in 1936 from a dietary fertility factor in rats, it was named tocopherol, from Greek τόκος 'tókos' 'birth' and φέρειν 'phérein' 'to bear or carry', that is 'to carry a pregnancy', with the ending -'ol' signifying its status as a chemical alcohol.

Alpha-tocopherol is the main source found in supplements and in the European diet, where the main dietary sources are olive and sunflower oils, while Gamma-tocopherol is the most common form in the American diet due to a higher intake of soybean and corn oil.

Tocotrienols, which are related compounds, also have vitamin E activity. All of these various derivatives with vitamin activity may correctly be referred to as "vitamin E". Tocopherols and tocotrienols are fat-soluble antioxidants but also seem to have many other functions in the body.

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