Though it may be hard to believe when you’re a smoker thinking about quitting, stopping the habit can actually improve your mental health rather than unsettle it.

Smokers often think their depression or anxiety will be worse if they quit smoking. Many see smoking as their “tool” for dealing with stress. Even some mental health professionals are reluctant to address smoking with their patients, for fear of making things more difficult for them.

But the opposite is actually true, according to a new study. Quitting smoking can significantly improve mental health in several different ways.

Lighting up a cigarette isn't relieving your stress or anxiety, it’s just easing your withdrawal symptoms.

British researchers analyzed the results of 26 studies measuring mental health markers such as anxiety, depression, positivity, psychological quality of life, and stress, before and up to six months after people quit smoking. They found that ratings of mental health improved on all measures after people quit smoking.

People in the studies had smoked an average of 20 cigarettes/day before stopping.

The benefits were seen in the general population and in those with more significant mental health issues.

Smokers should be “reassured that stopping smoking is associated with mental health benefits,” the authors say.

People often mistake their nicotine withdrawal symptoms for symptoms of mental health problems and think they are too tense to quit. Lighting up a cigarette isn't relieving your stress or anxiety, it’s just easing your withdrawal symptoms.

“Smokers experience irritability, anxiety, and depression when they have not smoked for a while,” the authors write, “and these feelings are reliably relieved by smoking thus creating the perception that smoking has psychological benefits, while in fact it is smoking that caused these psychological disturbances in the first place.”

The British researchers urge mental health professionals to take this phenomenon into account when helping smokers who have mental health issues like depression and anxiety. Doctors first have to be persuaded that quitting smoking will help their patients rather than harm them. Then they have to convince the patient of that as well.

Smokers who want to quit need to remember that as unpleasant as it may be in those first few weeks, quitting will actually make them much happier in long run.

The study was carried out by researchers at the universities of Birmingham, Oxford, and King's College London, and published in BMJ,The British Medical Journal.