The ambivalence of vitamin E in atherogenesis.

The early events in atherogenesis might be due to the oxidation of low- density lipoprotein. The antioxidant vitamin E, therefore, has received much attention as a potential anti-atherogenic agent. Recent mechanistic studies of the early stage of lipoprotein-lipid oxidation show that the role of vitamin E in this process is not simply that of a classical antioxidant. Unless additional compounds are present, vitamin E can have antioxidant, neutral or pro-oxidant activity. This more complex function is reflected in the results of vitamin-E-intervention studies of atherosclerosis in animals and of controlled prospective trials on the incidence of cardiovascular disease in humans, which, overall, are inconclusive.