Benefits of quitting smoking include improved lung function, improved circulation and decreased risk of diseases, such as heart disease, cancer and peripheral vascular disease. Health changes occur within 20 minutes after smoking a cigarette, and health continues to improve for years after quitting.
Benefits of quitting smoking, and how quickly they occur, vary for each person based on several factors, including how frequently and how much was smoked.
Lung function improves about two weeks to three months after the smoker has quit. Within one to nine months, the cilia in the lungs grow back, which helps keep the lungs clean. Ten years after quitting, the likelihood of being diagnosed with lung cancer is half that of a smoker.
Circulation in the gums and teeth improves to the level of a non-smoker within 10 to 14 days. Circulation throughout the body improves considerably within three months.
The smoker's heart attack risk drops within three months. Within one year, the risk of heart attack, coronary artery disease and stroke is less than half that of a smoker. Stroke risk continues to decline and reaches non-smoker levels within five to 15 years. By 15 years, risk of coronary artery disease is also that of a non-smoker.
For females that quit smoking, risk of death from all smoking-related diseases is equal with a non-smoker's after 20 years.