Acute effects of smoking cessation on antioxidant status

Smokers have a lower antioxidant status than nonsmokers which may contribute to their higher risk of vascular disease. To determine if antioxidant status improves 84 hr after smoking cessation, nine middle-aged fasting male smokers were studied. Six stopped smoking after the first day while three maintained their usual smoking pattern as ascertained by blood carboxyhemoglobin measurements. After smoking cessation, significant increases were seen in total plasma vitamin C levels (mean +/- SEM, 19 +/- 7%; P < 0.05) and in low density lipoprotein (LDL) alpha- and beta-carotene. No change after smoking cessation was detected in other parameters including plasma lipids, alpha-tocopherol, and copper-induced LDL oxidizability. However, there was a 34 +/- 13% (P < 0.05) increase in plasma gamma-tocopherol after smoking cessation explicable by increases in LDL and high density lipoprotein (HDL) gamma-tocopherol. That this increase was related to smoking status was supported by the correlation between the rise in plasma gamma-tocopherol and the selfreported daily cigarette consumption at entry into the study (r = 0.874, P = 0.016). Moreover, plasma gamma-tocopherol levels were significantly lower at baseline in the smokers studied (n = 9) when compared with a matched group of nonsmokers (1.43 +/- 0.19 vs. 2.87 +/- 0.51 mu M). These results point to a special relation between gamma-tocopherol and smoking status and indicate that increases in plasma antioxidant vitamins can be detected very soon after the cessation of smoking.