Twenty one healthy non-smoking males and nineteen healthy smoking males, matched for age and body weight, were investigated to outline the effect of cigarette smoking on the serum levels of iron (Fe), Copper (Cu), Zinc (Zn) and selenium (Se). As a marker for cigarette smoking, urinary cotinine was chosen and assessed for its simplicity and reliability. Smokers showed significantly decreased mean serum iron (P<0.02) and significantly increased mean urinary cotinine (P<0.001) levels as compared to non-smokers. However, there were no significant differences between the mean levels of serum Zu, Cu and Se in both groups. The low serum iron level in smokers could be explained by the impairment of iron uptake, absorption, mobilization and/or utilization due to both nicotine effect and hypovitaminosis C prevailing among smokers |