All About Antioxidants and Vitamins -

Vitamin E (Tocopherol)

Until recently, pharmacology textbooks have dismissed the fat soluble vitamin E as unimportant some have even said that it is of no medical relevance in humans. Tocopherol was first discovered in 1922 when it was found that female rats required an unknown substance in their diets to sustain normal pregnancies. Without it, they could ovulate and conceive satisfactorily, but within about 10 days the fetuses invariably died and were absorbed. Male rats deficient in this substance were also found to have abnormalities in their testes. For these reasons, vitamin E enjoyed a brief reputation as the 'anti sterility vitamin' and was, illogically, recommended as a treatment for infertility, although there was no reason to suppose that the people concerned were deficient in the vitamin. This was the kind of thinking that gave megavitamin therapy a bad name with the medical profession.

Vitamin E has also been used to try to treat various menstrual disorders, inflammation of the vagina and menopausal symptoms, but there is no evidence that it is of any value in these conditions.

Vitamin E was first isolated in 1936 from wheatgerm oil. It was found to be any one of a range of eight very complicated but similar molecules known as 'tocopherols'. It is almost insoluble in water but dissolves in oils, fats, alcohol, acetone, ether and other fat solvents. Unlike vitamin C, it is stable to heat and alkalis in the absence of oxygen and is unaffected by acids at temperatures up to 100oC. if exposed to atmospheric oxygen, it is slowly oxidized. This occurs more rapidly in the presence of iron or silver salts. It gradually darkens on exposure to light. Among the riches natural sources are seed germ oils, alfalfa and lettuce. It is widely distributed in plant materials. The international unit is equal to 1 mg of alpha tocopherols, natural vitamin E varies a little ijn its strength. But for practical purposes of dosage you can consider 1 international unit to be equivalent to 1 mg.