The number of cigarettes a person smokes per day and their current body mass index are predictive of changes in their weight after they quit, according to a recent study.
However, researchers at Penn State College of Medicine found that the amount of weight an ex-smoker gains might depend on their starting weights, Reuters Health reported.
Previous studies have found that for some it can 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.
"Nicotine is a metabolic stimulant (speeds up metabolism) and an appetite suppressant (makes people feel less hungry)," Susan Veldheer, lead author of the study, told Reuters Health. "So, when people quit, they tend to eat more because their appetite increases and they lose the metabolic boost they were getting from smoking . . . two things that then lead to weight gain."
For the study, researchers collected and analyzed data from more than 12,000 participants in the National Health and Nutrition Examination Survey, UPI reported. They looked at 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 compared the change in weight for non-smokers, continuing smokers and smokers who quit.
They found that 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, UPI reported.
The researchers then compared the weight gain in smokers who quit and smokers who continued smoking. What they found is 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," Veldheer said.
However, for those who smoke 25 or more cigarettes per day and those who were obese prior to quitting, 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," Veldheer said. "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 detailed in the International Journal of Obesity.
