Study: After quitting smoking, it can take up to 25 years for the body to recover

Researchers in South Korea have questioned the idea that the body quickly clears itself after years of smoking. Scientists have found out how long it takes for the cardiovascular system to recover.

Seung Young Shin, PhD, of Korea University Ansan Hospital, and his colleagues conducted a study of 5.3 million former smokers to examine the heart recovery phase after a person quits smoking. Participants were followed for four years and their health conditions, including heart attacks, strokes and heart failure, were recorded. Their smoking history and the number of cigarettes per day they quit were also taken into account.

The results showed that the body’s recovery from smoking depends on individual characteristics. Some participants began to notice improvement within a year, while others would need decades more. The study focused on “pack-years” of smoking. A pack-year is calculated by multiplying the number of packs a person has smoked by the number of years they have smoked.