Smoking cessation before age 45 was associated with approximately 90% reductions in excess mortality associated with continuing smoking, and quitting between ages 45 and 64 was associated with approximately 66% reduction in this excess risky. But the ideal age to quit smoking and match the risk of dying to that of someone who has never smoked is 35 years. These are the main conclusions of a study that followed 551,388 US adults, published in the journal ‘JAMA’.
Data were extracted from the National Health Interview Survey that was conducted through a questionnaire between January 1997 and December 2018 among adults aged 25 to 84 years at the time of recruitment. The participants were followed up until December 31, 2019.
In this study, smoking was associated with significantly higher all-cause mortality compared with never smoking, regardless of race, ethnicity, or gender. While quitting tobacco was associated with a reduction in excess deaths linked to continued smoking, with the largest declines among those who quit at younger ages.
“Thomson’s study provides the necessary data to establish a motivating next goal of stop smoking before age 35. To my knowledge, it is the third large cohort study to find that smokers who quit before age 35 have mortality rates that are no different than those who have never smoked,” he notes in a comment. Associated with the study was Dr. John P. Pierce, Cancer Control Program, Moores Cancer Center, La Jolla, California.
Participants were considered never smokers if they had not smoked at least 100 cigarettes in their lifetime, and those who had smoked at least 100 cigarettes in their lifetime were classified as ever smokers.
The time it has been since you stopped smoking is also decisive for life expectancy. The longer you don’t smoke, the more benefits. Thus, quitting smoking 5 to 14 years prior to study enrollment was associated with approximately 50% reductions in excess mortality among current smokers, whereas quitting 15 or more years prior to enrollment was associated with decreases of approximately 90% of this excess risk.