Weight concerns and smoking in a general population: the Inter99 study

No previous studies have explored weight concerns in relation to smoking habits, or investigated how weight concerns affect smoking cessation in a general population.

Inter99 is a population-based lifestyle interventional study, conducted in 1999-2001 in Copenhagen, Denmark, comprising 30-60 year old men and women. All daily smokers (N=2408) were offered help to quit. The baseline investigation (N=6784) was used for analysing associations of smoking status with weight concerns (cross-sectional design). To analyse how weight concerns affected smoking cessation we included the 1387 daily smokers attending 1-year follow-up; 221 of these were verified quitters (longitudinal design).

Daily smoking men and women had a significantly lower body mass index than never smokers (men: 3%, women 5%) but reported to be significantly less concerned of their weight (men: OR=0.64, 95%CI=0.4-0.9), women: 0.78(0.6-1.0)). Ex-smoking normal weight women were significantly more likely to be frequently concerned of their weight than never smoking normal weight women (OR=2.06, 95CI%=1.6-2.7). Fifty-two percent of the women and 32% of the men with a previous quit attempt reported that weight gain was a reason for relapse. Neither weight concerns nor eating patterns were predictive of point abstinence at 1-year follow-up.

Smokers are believed to be very concerned of their weight but in this population-based study, daily smokers more frequently ate what they wanted, had a lower BMI and were significantly less concerned of their weight than never smokers. Weight concerns and eating patterns did not predict abstinence at 1-year follow-up. It seems that weight gain and weight concerns are independent factors.