Does quitting smoking cause weight gain?

"Research shows that on average people who quit smoking gain around 5kg (11lbs) in the year after they stop smoking."

Dr Louisa Draper

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Many smokers worry that they will gain weight when they quit smoking. Although it’s common to gain weight - up to five kg on average - in the year after quitting, not everyone does. Simple lifestyle changes may help you avoid weight gain after giving up smoking.

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How does smoking affect your weight?

Research shows that on average people who quit smoking gain around 5kg (11lbs) in the year after they stop smoking. Smoking is known to speed up your metabolism, and when you stop, you need fewer calories.

If you are a heavy smoker you could need up to 200 fewer calories a day after giving up. Nicotine is also an appetite suppressant, so you might also find that your appetite increases as soon as you give up smoking.

Why do smokers who quit often report weight gain?

The main reasons are a slowing down of your metabolism (although only slightly) along with higher food intake as food starts to taste better without nicotine dulling your tastebuds.

Some people mistake a craving for nicotine for hunger, and some people find that they miss the physical ‘hand to mouth’ action of smoking a cigarette.

It’s easy to see how replacing a cigarette with a snack, enjoying your food more, having a stronger appetite and a lower metabolism can lead to weight gain if you’re not careful.

How much weight could I gain when I quit smoking?

Researchers at the Kyoto Medical Center in Japan studied 186 patients at a smoking cessation clinic and found that the more addicted they were to nicotine, the more likely they were to gain weight when they quit.

They looked at people with an average age of 60 who had been smoking an average of a pack of cigarettes or more a day. The people who smoked the most before they gave up gained the most in the three months after they gave up - on average about 2.5 pounds.

It was thought that because most of the people involved in the study were using some form of nicotine replacement therapy (NRT) or prescribed stop smoking medicine, this will have kept their weight gain to a minimum compared to people who give up ‘cold turkey’.

How can you prevent putting weight on when you quit smoking?

Smoking is a habit as well as an addiction - it’s not just the nicotine you’re weaning yourself off of. If you were previously smoking 20 cigarettes a day you would have been putting your hand up to your mouth out of habit something like 200 times a day. Without that physical action, some people can feel a little lost so they replace it with eating snacks instead. If this is you, an inhalator might help you replace the physical habit of picking up a cigarette.

Other ways to keep your mouth busy that don’t involve smoking could be chewing gum, sucking a boiled sweet or even flossing with a mint-flavoured dental floss.

Try to eat a little bit less as your metabolism stabilises. Reduce your normal portion sizes slightly - and remember that just because your food tastes better now you aren’t masking all the flavours with nicotine, you don’t have to eat more of it.

Eating more slowly will help you recognise when you’re full as it can take 20 minutes for your stomach’s ‘full’ signal to reach your brain.

Swap high calorie and fatty snacks for healthier options, like fresh fruit, nuts, dried fruit and vegetable sticks. Snack on these if a craving strikes. If you drink alcohol regularly, you could also try cutting out one alcoholic drink a day to prevent a relapse after drinking.

Regular exercise can help to raise your metabolism and counter the effects of the drop caused by losing nicotine. Just 30 minutes a day five days a week can help to increase your metabolism and cancel out any weight gain. It also keeps you busy in those times when you could be tempted to smoke again.

Can NRT help reduce weight gain?

The Japanese study mentioned above would suggest that replacing cigarettes with NRT (nicotine replacement therapy) can help reduce the amount of weight that you gain when you give up. You should make sure that you take all of your stop smoking medicines if they’ve been prescribed by a doctor, and keep up with the NRT of your choice to help keep cravings for nicotine to a minimum.

The less you crave nicotine, the easier it will be to stay away from the cigarettes and avoid replacing them with unhealthy snacks.

Don’t let worrying about your weight put you off quitting. You would need to put on at least four stone in weight before the risk to your health was even close to the risks of carrying on smoking.