Body mass index and lung cancer risk in never smokers

An elevated risk of lung cancer associated with lower levels of body mass index (BMI) has been reported in previous studies.1-9 However, the interpretation of the association between low BMI and lung cancer is complicated by the fact that weight loss may be a sign of smoking. In general, smokers tend to be lighter than non-smokers,1, 10-15 and it is believed that nicotine is responsible for the effect of smoking on body weight because nicotine appears to increase the metabolic rate. We have recently performed a casecontrol study of subjects participating in a mass-screening program and found an increased risk of lung cancer for lower BMI in male patients.16 Most of them were current smokers.16 However, the inverse Radiol Oncol 2006; 40(4): 239-44.