Research carried out in the US has found that those who stop smoking are able to sleep better.
The study, which was carried out at the University of Rochester's New York Medical Centre, discovered that smoking affects the circadian clock function in the lungs and the brain, leading to disrupted sleep, mood disorders, anxiety and depression.
Scientists monitored two groups of mice during the investigation. One group was exposed to cigarettes while the other was given pure air. Their energy levels and activity patterns throughout the day were analysed, with results showing that the mice that had been exposed to cigarette smoke were much less productive.
It was found that smoking reduced levels of an anti-aging molecule known as SIRTUIN1, which altered how well BMAL1 - a protein used in the operation of the circadian clock - worked.
Researchers are now hoping to expand on these discoveries. Irfan Rahman, one of the scientists who conducted the study, said: "We envisage that our findings will be the basis for future developments in the treatment of patients who are suffering with tobacco smoke-meditated injuries and diseases."