title: Differences in the association between smoking and relative body weight by level of education.
abstract: OBJECTIVE
  To investigate differences in the association between smoking and relative body weight by sex, age group and level of education.
  
  
  METHODS
  Cross-sectional study.
  
  
  METHODS
  About 36,000 men and women who participated in the Monitoring Project on Cardiovascular Disease Risk Factors in the Netherlands in 1987-1991.
  
  
  RESULTS
  The association between smoking and relative body weight differed by level of education. This difference was more pronounced among men than among women. Male heavy smokers had statistically significantly (P < 0.05) higher mean body mass index (BMI) than never smokers at high educational level, whereas they had a significantly lower mean BMI than never smokers at low educational level. In addition, ex-smokers had significantly higher mean BMI than never smokers in men with high education but not in men with low education nor in women. The difference in the association between smoking and relative body weight by educational level could not be explained by physical activity, fat intake or alcohol consumption nor by factors related to smoking behaviour.
  
  
  CONCLUSIONS
  The association between smoking and relative body weight may differ between subgroups within one population. Therefore adjustment for these subgroups, for example for educational level, may be inappropriate in studies of the BMI-smoking relationship. Also, stopping smoking may have difference effects on weight in these subgroups.
authors.affiliation: The Netherlands Institute for Health Sciences, Erasmus University Medical School, Rotterdam, The Netherlands.
authors.forename: A
authors.initials: A
authors.lastname: Molarius
authors.forename: J C
authors.initials: JC
authors.lastname: Seidell
mesh_terms: D000328:Adult; D015992:Body Mass Index; D001835:Body Weight; D003430:Cross-Sectional Studies; D004522:Educational Status; D005260:Female; D006801:Humans; D008019:Life Style; D008297:Male; D008875:Middle Aged; D012727:Sex Characteristics; D012907:Smoking