Heavy smokers and smokers who are obese gain more weight after quitting, said a new study.
For smokers, the number of cigarettes smoked daily and current body mass index (BMI) are predictive of changes in weight after quitting smoking, said researchers at Penn State College of Medicine.
Quitting smoking may lead to some weight gain but how much weight gain depends on the individual, it said. While previous research shows that for some it can be just a few pounds, but for others it can be more than 25 pounds.
However, factors that can help predict the amount of weight a smoker may gain are still not well understood.
“Many smokers are concerned about gaining weight after quitting smoking and this can be a barrier for them when they are considering whether or not to make a quit attempt,” said Susan Veldheer, a dietitian in the Department of Public Health Sciences, Penn State College of Medicine. “Being able to easily identify smokers who may gain more weight when they quit is important so that we can work with patients to tailor their treatment plan.”
The researchers analyzed data from 12,204 participants in the National Health and Nutrition Examination Survey and weighed the number of cigarettes smoked per day and body mass index before quitting, to see how these factors may have affected weight change over 10 years.
The researchers compared the change in weight for non-smokers, continuing smokers and smokers who quit. Then they compared the weight gain in smokers who quit and smokers who continued smoking and found that for smokers of fewer than 15 cigarettes per day, there was no significant difference in the 10-year weight gain between those who quit smoking and those who did not quit.
“This is good news for light to moderate smokers who are concerned about weight gain. It means that in the long term, quitting smoking will not make that big of an impact on their weight,” said Veldheer.
However, for smokers of 25 or more cigarettes per day and those who were obese prior to quitting — BMI of 30 or more — the amount of weight gain attributable to quitting was substantial.
Smokers of 25 or more cigarettes per day reported 23 pounds of smoking cessation-attributable weight gain and obese smokers reported 16 pounds of weight gain that could be directly attributed to quitting.
“Although this may seem like a lot of weight, it is important for all smokers to remember that quitting smoking is the single most important thing they can do for their health,” said Veldheer. “That being said, for heavy smokers and obese smokers, it may be a good idea to work on quitting smoking while also making other healthy lifestyle changes to control their weight.”
Findings were reported in International Journal of Obesity.