Vitamin E, also known as tocopherol or gestational glycoside, is a group of fat soluble compounds that include four tocopherols and four tocotrienols. It is found in edible oils, fruits, vegetables, and grains. Vitamin E cannot be synthesized by the body itself but need to be obtained from the diet or supplements. The main four components of natural vitamin E, including naturally-occurring d-alpha, d-beta, d-gamma and d-delta tocopherols. Compared to the synthetic form (dl-alpha-tocopherol), the natural form of vitamin E, d-alpha-tocopherol, is better retained by the body.

As a natural, oil-soluble antioxidant, tocopherol concentrate (a mixture of various isomers of natural tocopherol) is widely used in food processing industries such as whole milk powder, cream, meat products, processed seafood, dehydrated vegetables, fruit juices, frozen foods, and convenience foods. It also possesses both antioxidant and nutritional fortification functions in infant formula, therapeutic foods, and fortified foods. Its physiological effects include maintaining reproductive function and improving lipid metabolism. Clinically, it is used to prevent and treat recurrent miscarriage, threatened miscarriage, and menopausal disorders.