Natural Vitamin E Complex 400 I.U., provided by Douglas Laboratories, contains pure, natural, mixed tocopherols including alpha, beta, gamma and delta tocopherols which assure superior antioxidant protection. Vitamin E is one of the body’s most important antioxidant nutrients. Antioxidants protect healthy cells from oxidative and free radical damage. Free radicals are unstable chemicals formed in the body during metabolism and from exposure to environmental sources, such as air pollution and cigarette smoke. Free radicals are necessary for energy metabolism and immune function, but when an excessive number of free radicals are formed, they can attack healthy cells, especially their membrane lipids, proteins, and nucleic acids. This, in turn, is thought to degrade the structure and function of healthy cellular components. Vitamin E is an especially valuable antioxidant in the cell membranes, where it prevents oxidation of unsaturated fatty acids by trapping free radicals. This helps stabilize and protect cell membranes, especially red blood cells and tissues sensitive to oxidation, such as the lungs, eyes, and arteries. Vitamin E also protects the liver and other tissues from the free-radical damage of toxicants, such as mercury, lead, ozone, nitrous oxide, carbon tetrachloride, benzene, cresol, and various drugs.