One Cigarette Takes 20 Minutes Off Your Life Expectancy, According to New Study

Mar. 15, 2025

Stock image of a person smoking a cigarette.Photo: Erik Jonsson/EyeEm/Getty Images

“20 cigarettes at 20 minutes per cigarette works out to be almost seven hours of life lost per pack,” saidDr. Sarah Jackson, a principal research fellow in the UCL Alcohol and Tobacco Research Group and lead author of the study, perCNN.

Dr. Jackson and her team based their research on higher-quality data for mortality outcomes in Britain than had been available for previous studies.

Stock image of a person smoking a cigarette.© Getty Images

After adjusting for other variables that might influence the results, like smokers' socioeconomic status, researchers used an updated cigarette-per-day average of 11.5 for men and 9.5 per day for women, figures which were factored into the ultimate calculation for life expectancy.

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Stock image of a cigarette.Cludio Policarpo / EyeEm/Getty Images

Cludio Policarpo / EyeEm/Getty Images

In the United States, cigarette smoking causes one in every five deaths per year, according to theCenters for Disease Control and Prevention. The agency also says the life expectancy of a smoker compared to that of a non-smoker is at least 10 years shorter.

But according to theAmerican Lung Association, “the body begins to repair the damage and continues to repair itself for many years,” beginning as soon as 20 minutes after a smoker quits. The heart rate returns to normal after smoking, and over the next 12 to 24 hours, the level of carbon monoxide in the blood drops and the risk of heart attack is slashed as well.

“Stopping smoking is, without a doubt, the best thing you can do for your health,” Jackson said, per CNN. “And the sooner you stop smoking, the longer you’ll live.”

source: people.com