How Much Weight Will You Gain When You Quit Smoking?

One of the key drivers of smoking, especially amongst younger women, is to control their weight. No doubt cigarettes can reduce appetite and increase metabolic rate thus making it easier to avoid weight gain.

Unfortunately, this also means that many, who try to give up smoking, will probably put on a few pounds – but just how many pounds are we talking about?

This question was addressed in a paper by Henri-Jean Aubin and colleagues from the Université Paris Sud just published in the British Medical Journal.

The authors identified all studies listed in the Central Register of Controlled Trials (CENTRAL) and trials listed in Cochrane reviews of smoking cessation interventions (nicotine replacement therapy, nicotinic partial agonists, antidepressants, and exercise) for randomised trials of first line treatments (nicotine replacement therapy, bupropion, and varenicline) and exercise that reported weight change. They also searched CENTRAL for trials of interventions for weight gain after cessation.

A total of 62 studies were included in their analysis.

In untreated quitters, mean weight gain was 1.12 , 2.26, 2.85, 4.23, and 4.67 kg at one, two, three, six, and 12 months after quitting, respectively.

At 12 months after smoking cessation 13% of untreated quitters gained more than 10 Kg, 34% gained 5-10 Kg, 37% gained less than 5 Kg, and 16% actually lost weight.

There was no differences in changes in body weight between those who appeared concerned about their body weight and those who were not.

Treatment for smoking cessation (nicotine patch or buproprion) did not seem to have much effect in preventing weight gain.

Thus, it appears that smoking cessation is associated with a mean increase of 4-5 kg in body weight after 12 months of abstinence, with most of this weight gain occurring within the first three months of quitting.

However, there is a remarkable variation in weight change is large with about 16% of quitters losing weight and an almost equal number (13%) gaining more than 10 kg – a substantial weight gain by any standard.

If I had to guess, I’d say that those with the strongest addiction are the ones most likely to gain more weight, as they are also the ones most likely to shift their addiction from nicotine to food. Non-dependent smokers will likely fall into the lesser weight gain or even weight loss categories. At least that is a hypothesis that I’d like to see tested.

With or without weight gain, the risks of smoking by far outweigh the risks of even a 10 Kg weight gain – this why fear of weight gain should not discourage anyone from quitting.

On the other hand, as always, it may be far easier to prevent the weight gain in a quitter than to try and lose the weight once the pounds have been packed on.

Thus, prevention of weight gain should probably be an essential part of any smoking cessation strategy.

Edmonton, Alberta

ResearchBlogging.orgAubin HJ, Farley A, Lycett D, Lahmek P, & Aveyard P (2012). Weight gain in smokers after quitting cigarettes: meta-analysis. BMJ (Clinical research ed.), 345 PMID: 22782848