Vitamin E

Vitamin E
Tocopherol, or vitamin E, is a fat-soluble vitamin in eight forms that is an important antioxidant. Vitamin E is often used in skin creams and lotions because it is claimed by the manufacturers to play a role in encouraging skin healing and reducing scarring after injuries such as burns.

Natural vitamin E exists in eight different forms or isomers, four tocopherols and four tocotrienols. All isomers have a chromanol ring, with a hydroxyl group which can donate a hydrogen atom to reduce free radicals and a hydrophobic side chain which allows for penetration into biological membranes. There is an alpha, beta, gamma and delta form of both the tocopherols and tocotrienols, determined by the number of methyl groups on the chromanol ring. Each form has its own biological activity, the measure of potency or functional use in the body.

Sources of vitamin E
In foods, the most abundant sources of vitamin E are vegetable oils such as palm oil, sunflower, corn, soybean and olive oil. Nuts, sunflower seeds, seabuckthorn berries and kiwi fruit, and wheat germ are also good sources. Other sources of vitamin E are whole grains, fish, peanut butter, and green leafy vegetables. Fortified breakfast cereals are also an important source of vitamin E in the United States. Although originally extracted from wheat germ oil, most natural vitamin E supplements are now derived from vegetable oils, usually soybean oil.

The actual content of Vitamin E for rich sources is stated in the following list:
Wheat germ oil (215.4 mg/100 g)
Sunflower oil (55.8 mg/100 g)
Hazelnut (26.0 mg/100 g)
Walnut oil (20.0 mg/100 g)
Peanut oil (17.2 mg/100 g)
Soybean oil (14.6 mg/100 g)
Olive oil (12.0 mg/100 g)
Peanut (9.0 mg/100 g)
Pollard (2.4 mg/100 g)
Corn (2.0 mg/100 g)
Asparagus (1.5 mg/100 g)
Oats (1.5 mg/100 g)
Soybean (1.2 mg/100 g)
Chestnut (1.2 mg/100 g)
Coconut (1.0 mg/100 g)
Tomatoes (0.9 mg/100 g)
Carrots (0.6 mg/100 g)

Forms of vitamin E
Alpha-tocopherol is traditionally recognized as the most active form of vitamin E in humans, and is a powerful biological antioxidant.

The measurement of "vitamin E" activity in international units (IU) was based on fertility enhancement by the prevention of spontaneous abortions in pregnant rats relative to alpha tocopherol. It increases naturally to about 150% of normal in the maternal circulation during human pregnancies.

1 IU of vitamin E is defined as the biological equivalent of 0.667 milligrams of RRR-alpha-tocopherol (formerly named d-alpha-tocopherol, or of 1 milligram of all-rac-alpha-tocopheryl acetate (commercially called dl-alpha-tocopheryl acetate, the original d, l- synthetic molecular mix, properly named 2-ambo-alpha-tocopherol, is no longer manufactured).

High Gamma/Delta Vitamin E
All natural, High Gamma/Delta Vitamin E is the most complete formulation of key vitamin
E fractions offering high levels of gamma and delta tocopherol in addition to alpha tocopherol. Numerous studies point to the greater effectiveness of delta and gamma tocopherol fractions versus alpha tocopherol alone.

R, R,R tocopherol
The other R, R,R tocopherol vitamers are slowly being recognized as research begins to elucidate their additional roles in the human body.

Many naturopathic and orthomolecular medicine advocates suggest that vitamin E supplements contain at least 20% by weight of the other natural vitamin E isomers.

[ Tocotrienols
Tocotrienols, with four d- isomers, also belong to the vitamin E family. The four tocotrienols have structures corresponding to the four tocopherols, except with an unsaturated bond in each of the three isoprene units that form the hydrocarbon tail. Tocopherols have a saturated phytyl tail.

Source: Wikipedia