People who manage to quit smoking can expect to see an improvement in their mental health, a new study suggests.

According to UK researchers, while it is already well known that quitting smoking reduces the risk of a number of conditions, including cancer and heart disease, less is known about the effect on mental health.

In fact, some people believe smoking actually benefits their mental health, for example, they may smoke when stressed.

The researchers decided to investigate this further, by looking at changes in mental health after quitting the habit compared to continued smoking.

They analysed data from 26 relevant studies, involving adults with an average age of 44 who smoked around 20 cigarettes per day. All were followed up for an average of six months.

The researchers found that quitting smoking was associated with improvements in mental health, including stress, anxiety and depression. Those who quit were more likely to see an improvement in their psychological quality of life and were more positive than those who continued to smoke.

The results were similar among the general population and among people who had been diagnosed with a mental health disorder.

"Smokers can be reassured that stopping smoking is associated with mental health benefits. This could overcome barriers that clinicians have toward intervening with smokers with mental health problems. Furthermore, challenging the widely held assumption that smoking has mental health benefits could motivate smokers to stop," the researchers said.

Details of these findings are published in the British Medical Journal.

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