Stopping smoking is associated with considerable health benefits and large numbers of smokers want to quit. However, concern about weight gain is one of the reasons people often give for not being able to quit smoking. It often reinforces the decision to continue smoking, particularly in women and young people who may mistakenly believe that smoking is an effective way to control their weight. Even if an individual successfully quits smoking, weight gain can often be the factor that causes relapse. What can we do to help?