Researchers at the US National Institute of Environmental Health evaluated test results of approximately 16,000 people in 16 studies. Dr Normal Edelman, the senior scientific advisor for the American Lung Association said, “The message here is that smoking has an enormous, widespread impact on your genes. Most of it is reversible, but some is not. So if you smoke, you are going to alter your genetic makeup in a way that’s not totally reversible.” There were cases where even after five years of quitting, the genes had not recovered completely – leaving behind genetic footprints.
Talking about these genetic marks, researchers said these marks are caused by methylation, which is the process of alteration of DNA that can either deactivate a gene or alter its function, leading to diseases like cancer.
Roby Joehanes from Hebrew SeniorLife and Harvard Medical School said, “The encouraging news is that once you stop smoking, the majority of DNA methylation signals return to never-smoker levels after five years, which means your body is trying to heal itself of the harmful impacts of tobacco smoking.”