The honest answer is maybe. Some weight gain is normal. The average person who decides to quit smoking gains about seven pounds. But remember, this is the average. Some gain more, some less. And some people gain no weight at all.
If you’re worried about the health risks of gaining weight, doctors say that it would be almost impossible to put on enough pounds to make it worse than smoking. Ultimately, smoking is a bigger health risk than weight gain.
“If you’re thinking about quitting smoking, you shouldn't let a fear of weight gain deter you,” says Jennifer McClure, PhD, Kaiser Permanente Washington Health Research Institute’s lead tobacco scientist. “You can limit your potential weight gain by forming healthier diet and exercise habits.”
There are at least two reasons people gain weight after they quit smoking:
This doesn't mean that you are doomed to gain weight— just that you may need to take some extra steps to keep your weight stable. “Being aware of these factors can help you proactively take steps to maintain a healthy weight,” says Dr. McClure.
It’s the same for smokers and nonsmokers alike: The key to not gaining weight is to eat fewer calories and to burn more calories. Eat smart, incorporate low-calorie snacks to beat cravings, and increase your exercise.
From Kaiser Permanente Washington