Effect of supplementation with vitamin E on LDL oxidizability and prevention of atherosclerosis.

ABSTRACT

Supplementation of LDL with vitamin E is thought to protect LDL from oxidative modification and prevent the development of atherosclerosis. Large epidemiological studies have revealed that vitamin E levels in plasma are inversely correlated to the incidence of coronary heart disease. Double-blind placebo-controlled trials have reported that supplementation with vitamin E decreases the incidence of coronary events in coronary heart disease (CHD) patients. However, it is not clear how high a dose of vitamin E is needed to prevent formation of atherosclerosis. In animal studies, a diet containing 0.125% vitamin E increased its levels in plasma two-fold and prevented formation of early atherosclerotic lesions in the thoracic aorta of hypercholesterolemic rabbits. Dose-response studies in humans have reported that 400 IU/day vitamin E increased its levels in plasma two-fold and prolonged the lag time before LDL oxidation. It has been reported that oxidizability of LDL was correlated to the atherosclerotic score of coronary angiography in CHD patients. About 400 IU/day vitamin E, which increases its levels two-fold and prolongs sufficiently the lag time before LDL oxidation, might be beneficial in decreasing the individual risk of CHD.