Got to Quit to Live Longer

Smoking cessation helped more people live longer than reduced smoking

/ Author:  / Reviewed by: Joseph V. Madia, MD

(RxWiki News) When it comes to food and alcohol the phrase "everything in moderation" may apply. But when it comes to smoking, simply cutting back may not be enough. 

A recent study followed a large group of people for over 30 years to see whether cutting back on smoking was as effective as quitting smoking to help these people live longer.

The results of this study showed that only quitting smoking altogether, and not just reducing smoking, helped people live to see 75 years of age.

"To live longer, quit smoking altogether."

Carole Hart, PhD, of the Institute of Health and Wellbeing in the School of Public Health at the University of Glasgow in Scotland, led this investigation into whether cutting back on smoking, instead of quitting altogether, worked to reduce health risks over time.

For their study, these researchers used data from two long-term studies in Scotland that included 5,254 men and women between 40 and 64 years of age. Each participant was screened twice, once between 1970 and 1976 and again between 1977 and 1979.

The researchers looked at the medical records of the participants in 2010 to see how changes in smoking habits affected health. By 2010, not all of the participants were still alive.

During the first screening process, the participants were asked how many cigarettes they smoked per day: 0, one to 10, 11 to 20, or 21 or more.

During the second screening process, the participants were asked again about their smoking and then categorized as "increased," "maintained," "reduced" or "quit."

Between the first and second screening, 14 percent of participants from one of the two studies increased their smoking, 59 percent maintained, 10 percent reduced and 17 percent had quit smoking.

Between the first and second screening, 10 percent of participants from the other of the two studies increased their smoking, 65 percent maintained, 13 percent reduced and 13 percent had quit smoking.

The results of the 2010 analysis showed no evidence of a lower risk of dying among smokers who reduced the number of cigarettes they smoked per day compared to smokers who maintained smoking the same number of cigarettes per day.

Among study participants who had increased their smoking, only 54 percent lived to see 75 years of age. Of those who maintained their smoking, 59 percent lived to see 75 years of age. Among smokers who reduced the amount they were smoking, 56 percent lived to see 75 years of age.

Overall, 67 percent of people who quit smoking lived to see 75 years of age.

The study authors concluded that cutting back on smoking should not be promoted as a means of reducing the risk of death.

These authors suggested that cutting back on smoking to help a person wean off smoking altogether may help a person eventually quit, but that a person would have to quit to experience health benefits of lowing the risk of death.

"[C]ontinued smoking, even at low levels, clearly carries substantially increased health risks. Reducing the frequency of smoking should thus primarily be recommended as a short-term step toward cessation," the study authors wrote.

This study was published in July in the American Journal of Epidemiology.

The National Health Service Health Scotland, the British Heart Foundation, Cancer Research United Kingdom, the Economic and Social Research Council, the Medical Research Council, and the National Institute of Health Research provided funding for this project.

Reviewed by: 
Review Date: 
July 5, 2013
Last Updated:
August 19, 2013