Serum vitamin C and thiocyanate levels in smokers

ABSTRACT

Twenty-eight healthy males, non-smokers as well as 28 healthy male smoker subjects matched for age and body weight constituted the material of the present study. Serum thiocyanate and plasma ascorbic acid levels were estimated during fasting in both groups. Moreover, each of the smoker subjects were asked to smoke two cigarettes within five to ten minutes after which by ten minutes serum thiocyanate and plasma ascorbate were measured again to evaluate the immediate effects of smoking on the previous two parameters. Smokers showed significantly lower mean plasma vitamin C and significantly higher mean serum thiocyanate levels compared -to nonsmokers. Also, in smokers, plasma vitamin C mean level after smoking 2 cigarettes was significantly lower compared to the corresponding mean in the same subjects before smoking. Moreover, plasma ascorbic acid levels were inversely and significantly correlated to the age of subjects whether smokers [n 28, r-0.4l2. P<0.05] or non-smokers [n 28. r-0.577. P<0.05], but in smokers in addition, such levels were also inversely and significantly correlated to the number of cigarettes smoked per day [n=28, r=-0.515, P<0.05] and to the duration of smoking in years [n=28. r=-0.480, P<0.05]. Low vitamin C levels in smokers could result from decreased intake, decreased absorption, increased excretion and increased usage for synthesis of catecholamines whose synthesis and release are stimulated by nicotine of cigarette smoking