ROLE OF VITAMIN E ON OXIDATIVE STRESS IN SMOKERS

Abstract

Cigarette smoke contains numerous oxygen free radicals that when inhaled, overwhelm antioxidant defenses and produce a condition of oxidative stress. This study investigated whether or not supplementation with vitamin E can affect the state of oxidative stress in healthy smokers. In this randomised double blind trial, 32 smokers received 200 mg of vitamin E or placebo daily for 8 weeks. All smokers in the vitamin E group completed the trial whilst only nine in the placebo group completed the trial. Plasma vitamin E concentrations increased significantly [P<0.02] in the vitamin E group. The release of malondialdehyde [MDA] from erythrocytes was not significantly different between the two groups at baseline and was clearly reduced [P<0.01] after 8 weeks of vitamin E supplementation. Vitamin E increased erythrocyte superoxide dismutase activity [P<0.02] and decreased gluthathione peroxidase activity [P<0.02]. No changes were detected in plasma MDA. We conclude that daily supplementation with 200 mg of vitamin E for 8 weeks improved the oxidative stress state in smokers.