Staying Active Helps Reduce Weight Gain in the Belly After Quitting Smoking

A recent 10-year twin study was published on June 29 in the International Journal of Obesity entitled, "Associations of smoking status and leisure-time physical activity with waist circumference change—10-year follow-up among twin adults." The study suggests that staying physically active after quitting smoking may significantly reduce the weight gain in the belly often seen in former smokers.

The researchers tracked pairs of twins in Finland who quit smoking at different times and maintained varying levels of activity. Those who remained more active showed far less gain in central body fat, referred to as weight circumference (or WC) in the study, than their sedentary counterparts. Leisure-time physical activity (LPTA) was shown to be of particular importance. "Among those who quit daily smoking, the mean WC increase was 8.4 cm... Quitters who smoked daily at baseline increased WC by about 2 cm more than continuing smokers... Smoking cessation seems to be associated with WC increase, but familial confounding may be involved in this process. LTPA appears to mitigate increase in WC independently of smoking status and familial influences," the study explains.

Quitting smoking can add as much as 10 years to life expectancy, but the possibility of weight gain can give pause to potential quitters. The researchers suggest that physical activity, particularly leisure-time movement like walking or cycling, may blunt the metabolic changes that lead to weight gain after nicotine withdrawal. Since fear of post-quit weight gain sometimes discourages people from quitting, these findings offer a practical solution—move more to offset the changes.

The findings strengthen prior evidence that smoking cessation doesn’t have to result in long-term weight issues if exercise is part of the plan. As quitting remains one of the best decisions for long-term health, adding even moderate movement may help people stick with it and feel better during the process.