There is a paucity of Indian data on the vitamin E content of foods as well as vitamin E requirement by Indian population. Vitamin E deficiency is not prevalent in our country and ICMR has not yet established a daily allowance of vitamin E for our Indian population. Since the requirement for vitamin E depends on the intake of unsaturated essential fatty acids (linoleic and linolenic acids), the requirement for vitamin E suggested is 0.8mg/ g of essential fatty acids.

A person consuming a large amount of PUFA needs more vitamin E. Fortunately, vitamin E and PUFA tend to occur together in the same foods.

The Food and Nutrition Board in the United States has recommended levels of vitamin E intake for various age groups. They have been given in the below table.

Vitamin E is a fat-soluble antioxidant and one of body’s prime defenders against oxidation. It protects the lipids and other vulnerable components of the body cells and their membranes from oxidation.

Its function as an antioxidant is particularly important in tissues rich in polyunsaturated fatty acids (PUFA) and tissues which are in constant contact with oxygen, like lungs. Vitamin E is particularly effective in preventing the oxidation of PUFA, other lipids, as well as related compounds such as vitamin A. Thus, vitamin E protects the lipids of the membranes from oxidative damage due to highly reactive oxygen species and other free radicals. Vitamin E reduces the harmful free radicals to harmless metabolites. This process is called ‘free radical scavenging’.

Vitamin E protects the unsaturated lipids and vitamin A because it can accept oxygen and get oxidised itself, thereby acting as an antioxidant. It thus exerts a sparing action on vitamin A by preventing its oxidation. Vitamin E also protects fats and oils from oxidation and rancidity, thereby acting as a preservative.

Recent researches have shown that vitamin E may play a role in reducing the risk of heart disease by protecting LDL (low density lipoprotein) cholesterol against oxidation. Vitamin E exerts an especially important antioxidant effect in the lungs, where the exposure of the cells to oxygen is maximal. Vitamin E’s antioxidant property protects not only the lung tissues but also the red blood cells and white blood cells that pass through the lungs. Vitamin E also protects the lungs against air pollutants. In its antioxidant function, vitamin E acts synergistically with selenium (a trace element) to protect the cells from the damaging effects of oxygen species and free radicals. In fact, selenium and vitamin E both have a sparing effect on each other, and also reduce the body’s requirement for each other.

antioxidant function of vitamin E and other nutrients protects our body against conditions related to oxidative stress, such as aging, air pollution, arthritis, cancer, cardiovascular diseases, diabetes and infections. A lot of research is being conducted on the role of vitamin E in the above mentioned areas.

False hopes

When vitamin E was discovered in 1922, it was termed as the ‘antisterility factor’ because of its role in fertility and preventing abortions in rats. However, any of these functions have not yet been proven in humans. It is, therefore, a misnomer to call vitamin E the ‘reproduction vitamin’. Till date, it has not been proven that vitamin E can improve sexual potency, prevent baldness, improve athletic performance or increase life-span in humans. Nonetheless, vitamin E’s role as an antioxidant in protecting the membranes in our bodies from damage, is extremely important.

In 1922, Evans and Bishop discovered another fat-soluble factor and named it vitamin E. This factor was found to be essential for reproduction in rats. Although the same functions have not been proven in humans, the vitamin was named tocopherol (vitamin E) from the Greek tokos meaning ‘childbirth’, pherein meaning ‘to bear’ and ol signifying an alcohol.

Vitamin E comprises a group of compounds known as tocopherols and tocotrienols. These are of different types – alpha, beta, gamma and delta. Of these, alpha-tocopherol is the most active and is also the form which is most abundant in foods.

Being fat-soluble in nature, vitamin E and other fat-soluble vitamins are absorbed along with fat in the presence of bile acids. Small amounts of vitamin E are present in all body tissues, but the bulk is stored in muscle, liver, and adipose tissue.

recognised that vitamin E plays a fundamental role in the normal metabolism of all cells. Its deficiency can affect several organ systems. Its functions are related to several other nutrients. Together with some other nutrients, it plays an important role in the defence mechanisms of the body.

Vitamin E is stable to high temperature and acids but it gets oxidised easily in the presence of oxygen. Thus, it acts as an antioxidant. Vitamin E is soluble in fats and organic solvents but insoluble in water. Normal cooking temperatures are not destructive but freezing, processing and frying result in vitamin E losses.