Definition

A natural fat-soluble antioxidant with potential chemopreventive activity. Also known as tocopherol, vitamin E ameliorates free-radical damage to biological membranes, protecting polyunsaturated fatty acids (PUFA) within membrane phospholipids and within circulating lipoproteins. Peroxyl radicals react 1000-fold faster with vitamin E than with PUFA. In the case of oxygen free radical-mediated tumorigenesis, vitamin E may be chemopreventive.