Vitamin E

Vitamin E refers to a group of eight fat-soluble compounds that include both tocopherols and tocotrienols. Of the many different forms of vitamin E, is the most common in the North American diet. It can be found in corn oil, soybean oil, margarine, and dressings. The most biologically active form of vitamin E, is the second-most common form of vitamin E in the diet. This variant can be found most abundantly in wheat germ oil, sunflower, and safflower oils. As a fat-soluble antioxidant, it stops the production of reactive oxygen species formed when fat undergoes oxidation. Amounts over 1,000 mg per day are called Hypervitaminosis E, as they may increase the risk of bleeding problems and vitamin K deficiency.

The primary role of Vitamin E appears to be as an antioxidant. It is believed that it also functions as an activator in certain enzymatic reactions. Vitamin E plays an important role in the protection of Vitamin A, carotene and ascorbic acid from oxidation in the digestive tract and in the body cells. 

By accepting oxygen itself, it helps prevents the oxidation of Vitamin A. In the body tissue Vitamin E plays another important role by reducing the oxidation of the polyunsaturated fatty acids, thereby helping to maintain the integrity of the cell membranes. Thus the protective of Vitamin E enhances the efficient use of vitamin A and ascorbic acid.

In many species of animals deficiency of vitamin E is known to cause reproductive failure in the form of permanent and temporary sterility. No such effect has so far been proved in respect of human being.

Sources
Many vegetables oils such as wheat-germ oil are good sources of tocopherols although they are high in poly unsaturated fatty acids. Good concentration of vitamin E is present in the dark green leafy vegetables, nuts and legumes as well as whole grain cereals. Although food of animal origin is low in vitamin E, liver, heart, kidney, milk and eggs are the animal sources of this vitamin. While human milk provides an adequate amount of vitamin E to the infant, Cow’s milk contains very little of this vitamin.

Daily Allowances.
There is a satisfactory level of vitamin E in the diet through the intake of vegetable oil and margarine. Since this vitamin is also widely distributed in many other food items, a deficiency does not normally develop in human beings. The need for vitamin E is higher when there is an increased intake of polysaturated fatty acid.

Deficiency
Vitamin E deficiency results in increased haemolysis (breakdown) of the red blood cells leading to anaemia. Premature Infant also shows a low level of tocopherol. In some species of animals Vitamin E deficiency is known to cause reproductive failure. In human being vitamin E deficiency is not frequently reported.

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