The primary function of vitamin E is as an antioxidant, which is very important. Vitamin E is protective because it helps reduce oxidation of lipid membranes and the unsaturated fatty acids and prevents the breakdown of other nutrients by oxygen. This protective, nutritional antioxidant function is also performed and enhanced by other antioxidants, such as vitamin C, beta-carotene, glutathione (L-cysteine), and the mineral selenium.
Oxidation in our body of such substances as the fat molecules, particularly from polyunsaturated fats, and from eating other oxidized fats such as hydrogenated oils and rancid oils, causes the genesis of free radicals, unstable molecules that can lead to cellular and tissue irritation and damage, which lead to chronic inflammation, especially in the vascular lining.
Excess free radical formation comes from a variety of chemical reactions in the body and is the biochemical basis of many diseases, such as atherosclerosis, heart disease, hypertension, arthritis, senility, and probably even cancer. A number of experiments have shown that the antioxidant nutrients such as vitamin E can protect the tissues from oxidation and free radicals.