Australasian Science: Australia's authority on science since 1938

How Much Weight Do Quitters Gain?

Fear of weight gain is a commonly cited reason for not quitting smoking, despite evidence that quitting will result in better overall health.

Now researchers at the University of Tasmania’s Menzies Institute for Medical Research have quantified the weight gain for smokers who quit, and the difference in weight gain between quitters and continuing smokers.

Jing Tian and Dr Seana Gall analysed data from 63,403 quitters and 388,432 continuing smokers, and found that people who quit smoking gained an average of 4.1 kg over about 5 year – 2.6 kg more than the weight gained by continuing smokers.

The difference in weight gain was greater in women than men, and greater in studies conducted in North America than in Asia. “The reasons for the weight gain after smoking are complex but probably related to changes in brain activity and metabolism after quitting,” said Gall, who was senior author of the research published in Obesity Reviews.

“We don’t want our findings interpreted as an incentive to keep smoking,” Gall said. “Other studies suggest that this small amount of weight gain does not offset the many health benefits of quitting smoking.