Smokers who quit are shown to benefit from an improved mood, according to a recent review of past studies.
Quitting smoking was associated with improvements in mental health similar to taking an antidepressant drug, a team of UK researchers found.
"The main message is that when people stop smoking, they feel better than they did when they were smoking," Dr. Paul Aveyard, one of the review's authors, told Reuters Health.
For the review, researchers compiled data from 26 studies related to smoking cessation. Participants in these studies smoked an average of 20 cigarettes per day initially, and their mental health was assessed before they quit smoking and about six months after.
Compared to people who continued to smoke, the studies showed drops in anxiety, depression and stress and improvements in psychological quality of life among quitters.
One expert not involved in the review noted that withdrawal symptoms from tobacco, such as anxiety, can be confused with mental health problems in smokers.
"It's possible that the emotional withdrawal symptoms are interpreted as an acute worsening of psychiatric symptoms," said Brian Hitsman of the Northwestern University Feinberg School of Medicine in Chicago.
Withdrawal symptoms can also manifest themselves as simply being the result of stress.
"People who quit smoking may feel grumpy, irritable and bad - those feelings are similar to feelings of stress and people conflate the two," Aveyard added.
It is still widely believed that smoking "calms the nerves," but Aveyard and his colleagues are confident quitting is linked to improved mental health.
"It's getting harder and harder to find any real benefits of smoking," Dr. Prabhat Jha, of the University of Toronto Center for Global Health Research in Canada, said.
