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Vitamin E
Family of eight lipid-soluble compounds (four tocopherols, four tocotrienols), with α-tocopherol the only form maintained in plasma by hepatic α-tocopherol transfer protein (α-TTP) and the form on which the RDA (15 mg/d adult) is based.
Also: Alpha-tocopherol, α-Tocopherol
α-Tocopherol is the principal lipid-phase chain-breaking antioxidant, terminating lipid peroxidation by donating a phenolic hydrogen to lipid peroxyl radicals. Other tocopherols and tocotrienols (γ-tocopherol especially) have distinct activities not captured by the α-tocopherol-based RDA. Deficiency is rare except in fat malabsorption or AVED (ataxia with vitamin E deficiency, α-TTP mutations). Supplementation trials for cardiovascular and cancer prevention have been largely negative or harmful at high doses.
How each textbook covers it
duyff-complete-food-and-nutrition-guide-5e
Modern Nutrition in Health and Disease, 12th ed. — Ch 21: Vitamin E
α-Tocopherol is the principal lipid-phase chain-breaking antioxidant, terminating lipid peroxidation by donating a phenolic hydrogen to lipid peroxyl radicals. Other tocopherols and tocotrienols (γ-tocopherol especially) have distinct activities not captured by the α-tocopherol-based RDA. Deficiency is rare except in fat malabsorption or AVED (ataxia with vitamin E deficiency, α-TTP mutations). Supplementation trials for cardiovascular and cancer prevention have been largely negative or harmful at high doses.
Related terms
Oxidative stress, Polyphenols, Vitamin C