How Much Weight Will You Gain After You Quit Smoking?

  • Share
  • Read Later
Comstock Images / Getty Images

Your heart and lungs will thank you for kicking your cigarette habit, but your waistline may not. A new study of weight gain after quitting finds that ex-smokers may end up packing on a few more pounds than they expected.

On average, say French and British researchers, people may gain about 10 lbs. after kicking the habit. That’s substantially higher than the roughly 6 lbs. often quoted in quit-smoking literature handed out to smokers, and double the 5 lbs. that many female smokers report being willing to tolerate before attempting to quit, according to the authors.

Weight gain has long been associated with quitting — not surprisingly, considering that nicotine is an appetite suppressant and a stimulant — and many people who start smoking or don’t quit cite fear of ballooning weight as a reason. But the new findings back up what any doctor will tell you: you’re still better off quitting.

(MORE: Should Movies With Smoking Be Rated R?)

For the new study, published in BMJ, the research team closely examined data from 62 previous randomized controlled trials of quit-smoking programs involving people who were motivated to quit. All of the studies assessed weight changes among participants, and the researchers separated out those who used quit aids like nicotine replacement therapy or the drugs buproprion (Zyban) or varenicline (Chantix) from those who quit without treatment. “We kept these groups separate because these pharmacotherapies could have a small effect on weight gain in the short term,” the authors write.

The authors looked at weight gain in participants who had succeeded in quitting smoking for at least 12 months. On average, quitters who didn’t rely on drugs or nicotine replacement to kick cigarettes, had gained 2.5 lbs. one month after quitting, 5 lbs. at two months, 6.3 lbs. at three months, 9.3 lbs. at six months, and 10.3 lbs. at 12 months.

But these numbers aren’t set in stone, the researchers say. The study found great variability in the amount of weight people gained. Some people even lost weight. For instance, says study author Henri-Jean Aubin, professor of psychiatry and addiction medicine at Hôpital Paul Brousse, in France, a quarter of ex-smokers gained less than 2 lbs. or lost weight after quitting, while an equal number gained more than 17 lbs.

(MORE: Social Smoking Is No Better for Your Brain)

“Although our study has confirmed that there is substantial weight gain on average during the first year of continuous abstinence, a prediction of average weight gain will be wrong for most individual smokers,” says Aubin, adding, “The good news is that after the first [three months], weight gain is decelerating substantially. Nearly 20% of the smokers actually lose weight after one year of continuous abstinence.”

So, while it’s true that some quitters will gain a significant amount of weight, a great many will actually lose extra fat — an added health bonus on top of putting out cigarettes for good.

In an editorial accompanying the new study, Esteve Fernández, an associate professor of epidemiology at the University of Barcelona, and Simon Chapman, a professor of public health at the University of Sydney, argue that many real-world quitters may fare better than those included in the review. The data in the study include only those smokers who volunteered for clinical trials and attended smoking-cessation clinics, a “self-selecting minority of smokers who may differ in important respects from those who quit without professional assistance,” the authors write:

Those who decide they need help to stop smoking tend to lack self-efficacy. They might have similar problems with the dietary and physical activity behaviors important in weight control. So these results may not be generalizable to all smokers who quit because two-thirds to three-quarters of ex-smokers stop smoking without professional help or interventions.

(MORE: Can the Quit-Smoking Drug Chantix Help People Kick Alcohol, Cocaine?)

Fernández and Chapman urge potential quitters not to be put off by the new findings, noting further that previous studies have found that ex-smokers may gain weight in the short term after quitting, but not in the long term. “Modest weight gain does not increase the risk of death,” they write. “Smoking does.”

Aubin says physicians should stress the long-term benefits of quitting to their patients and encourage them to start exercising, which not only helps reduce weight gain, but also may help them stay quit.

“Quitting smoking at age 40 increases life expectancy by nine years, even taking into account the possible post-cessation weight gain. If their smoking patients do not take steps now to quit smoking despite the risk of weight gain, when will they do it?” he says.