Burton, G.W., Traber, M.G., Acuff, R.V., Walters, D.N., Kayden, H., Hughes, L., and Ingold, K.U. Humana Plasma and Tissue Alpha-Tocopherol Concentrations in Response to Supplementation with Deuterated Natural and Synthetic Vitamin E. Am. Kitabchi, A.E., Wimalasena, J. and Barker, J. Specific Receptor Sites for Alpha-Tocopherol in Purified Isolated Adrenocortical Cell Membrane. Hosomi, A., Arita, M., Sato, Y., Kiyose, C., Ueda, T., Igarashi, O., Arai, H., and Inoue, K. Affinity for Alpha-Tocopherol Transfer Protein as a Determinant of the Biological Activities of Vitamin E Analogs. The first, and most important, is as an antioxidant that protects cells and other body components from free radical attack. Oxidative damage resulting from free radical attack has been linked to the onset of premature aging, cancer, coronary heart disease, cataracts and an array of degenerative diseases.
Vitamin E stimulates the immune response.
Some studies have shown lower incidence of infections when vitamin E levels are high, and vitamin E may inhibit cancer initiation through enhanced immunocompetence. Vitamin E also has a direct chemical function. It inhibits the conversion of nitrites in smoked, pickled and cured foods to nitrosamines in the stomach. Nitrosamines are strong tumor promoters. Vitamin E has a regulatory effect on gene expression.