People who smoke heavily and have a higher body mass index (BMI) are more likely to gain weight after quitting smoking, according to new research at Pennsylvania State College of Medicine.
“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 registered dietitian in the Department of Public Health Sciences, Pennsylvania 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.”
It is well known that quitting smoking may lead to some weight gain but just how much depends largely on the individual. For some it may be just a few pounds, but for others it can be more than 25 pounds. Unfortunately, factors that can help predict the amount of weight a smoker may gain are not well understood.
To better understand the relationship between quitting smoking and weight gain, the researchers analyzed data from 12,204 participants enrolled in the National Health and Nutrition Examination Survey. They looked at participants’ BMIs and the number of cigarettes they smoked per day before quitting to see how these factors may have affected weight change over 10 years.
The researchers compared the former smokers’ change in weight with that of non-smokers and continuing smokers. “People tend to put on some weight over time and everyone in the study gained weight. The non-smokers gained about a pound a year for 10 years,” said Veldheer.
The researchers then compared the weight gain in former smokers and smokers who continued smoking. For those who smoke(d) 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 quitting-related weight gain, and obese smokers reported 16 extra pounds of weight gain.
“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.”
The findings are published in the International Journal of Obesity.