Vitamin E (d-Alpha-Tocopherol)

Direct Answer

Vitamin E is the principal fat-soluble peroxyl radical-scavenging antioxidant protecting cellular polyunsaturated membrane phospholipids. Adult RDA is 15 mg (22.4 IU) of d-alpha-tocopherol, with a Tolerable Upper Limit of 1,000 mg (1,500 IU)/day.

Source: NIH ODS / EFSA · Last reviewed Aug 28, 2026

Specs

Nutrient Type	Fat-Soluble Chromanol Lipophilic Vitamin
Adult RDA / RDI	15 mg / day (22.4 IU) of 2R-alpha-tocopherol
Tolerable Upper Limit (UL)	1,000 mg / day (1,500 IU synthetic) (Excess impairs Vitamin K clotting cascade)
Chemical Forms	RRR-alpha-Tocopherol (Natural d-alpha), all-rac-alpha-Tocopherol (Synthetic dl-alpha), Gamma/Delta-Tocopherols
Primary Biological Function	Breaks lipid peroxidation chain in PUFA cell membranes, protects LDL from oxidative modification, maintains erythrocyte membrane integrity
Deficiency Condition	Hemolytic anemia, Spinocerebellar ataxia, Peripheral neuropathy, Loss of vibratory/proprioceptive sense
Top Whole Food Sources	Wheat Germ Oil, Sunflower Seeds, Raw Almonds, Hazelnuts, Sunflower Oil, Spinach, Hass Avocado
Hepatic Alpha-TTP Specificity	The liver secretes only alpha-tocopherol into VLDL via Alpha-Tocopherol Transfer Protein (alpha-TTP); other tocopherols are degraded in bile

Antioxidant Regeneration by Vitamin C

When alpha-tocopherol neutralizes a membrane lipid peroxyl radical, it becomes an alpha-tocopheroxyl radical. Water-soluble ascorbic acid (Vitamin C) at the cell membrane interface reduces the tocopheroxyl radical back into active Vitamin E.