New York: Scientists have discovered one of the ways in which smoking cigarettes makes you age faster and puts you at risk of diseases such as chronic obstructive pulmonary disease (COPD) and lung cancer.

Researchers at the University of Rochester in the US found that the toxins in cigarette smoke wipe out a gene that protects the body against premature ageing.

Dr Irfan Rahman, associate professor of environmental medicine and an investigator in the University of Rochester’s Lung Biology and Disease Programme, noted: “You can be 45 years old and look great on the outside, but if you are a smoker or former smoker, your lungs can easily be 60 years old because of the chemical assault.”

Cigarettes contain around 4,700 toxic chemical compounds which decrease the lungs’ production of SIRT1, a protein that helps to regulate chronic inflammation, cancer and ageing.

The University of Rochester team, in collaboration with Finland’s Helsinki University Hospital, confirmed that levels of SIRT1 are significantly lower in smokers than in non-smokers.

This in turn affects genes that help to detoxify the airways, speeding up the ageing process of the lungs.

The findings are published in the American Journal of Respiratory Critical Care Medicine and in the American Journal of Physiology.