Background: The aim of the present study was to examine the association between smoking status and relative body weight at different educational levels in Finland during 1978-1995.
Methods: The data for the study were derived from separate cross-sectional health behavior surveys conducted annually by the National Public Health Institute (n = 3,418-5,037, response rate 68-84%). Relative weight was compared among current smokers, ex-smokers, and never smokers. Mean body mass index (BMI) was used as the measure of relative weight. Educational level was measured by the number of school years.
Results: During 1978-1995, relative weight increased in all smoking categories. Among men, ex-smokers weighed most, irrespective of study year or educational level, whereas among women ex-smokers showed a mean BMI comparable with that of never smokers. Among current and never smokers, both men and women, the association between smoking status and mean BMI varied according to educational level: current smokers weighed less than never smokers at the lowest educational level, whereas at the highest educational level they weighed more than never smokers.
Conclusions: The association between smoking status and relative weight varied according to educational level. The finding suggests that the association between smoking status and relative weight is modified by social and behavioral factors.