Prev NEXT  


Is quitting smoking contagious?

Quitting Smoking Together

If the woman on the left quit smoking, both gentlemen with her are more likely to follow suit. But then they'd be forced to talk to each other.
If the woman on the left quit smoking, both gentlemen with her are more likely to follow suit. But then they'd be forced to talk to each other.
Matt Cardy/Getty Images

Can quitting smoking with another person or group of people improve your chances of success? Dr. Nicholas Christakis and Dr. James Fowler sure think so. They published a study in the New England Journal of Medicine in May 2008 that showed cessation success rates when pairs and groups of people tried to quit together.

The study -- the Framingham Heart Study -- is a federally funded, long-term health research examination of more than 12,000 residents in the Boston, Mass. suburb of -- you guessed it -- Framingham. The health of the people of Framingham was studied over a 32-year period beginning in 1971. Through the supplied contact information, a web of personal ties was established, linking together the participants through their relationships with each other -- friends, co-workers, relatives and neighbors. This web was a key element to carrying out the study of peer influence on smoking cessation. (For more common questions to answers on Smoking Cessation, visit


Out of the 12,000 subjects, there was a roughly 5,000-person subset of smokers, which is about on par with national averages. These 5,000 people had 53,000 social ties with other people in the Framingham study. For the purposes of the study, anyone who smoked more than one cigarette a day was classified as a smoker. The researchers mined information at seven different time points, each about three years apart over a 21-year period. The research indicated that people do tend to successfully quit smoking when giving it a go with another person or group of people.

Not surprisingly, close relationships had the most impact. People with spouses who quit smoking were 67 percent less likely to smoke. With a close friend, those chances move to 36 percent. Co-workers in smaller, more intimate businesses were 34 percent less likely to smoke if a workmate quits. Siblings quitting made the subjects 25 percent less likely to smoke.

The study also confirms that smokers can be influenced by people up to three degrees of separation from themselves. Let's break that down. Say subject "A" is a smoker and he has a friend, subject "B." Subject "B" has a friend, subject "C," who also is a smoker. If subject "A" quits smoking, subject "C" is 29 percent less likely to smoke, even if he doesn't know subject "A" personally. The study even took it one step further, showing that if subject "C" had a friend, subject "D" -- he would be 11 percent less likely to smoke if subject "A" quit. Got all that?

The research also showed that people tend to quit in groups. Smoking clusters formed over the years in Framingham, but as people in the cluster quit, the smokers moved to the outskirts of the social group. These smokers were also more likely to seek out other smokers, forming new clusters.

Some interesting revelations into how education affected smoking cessation were made as well. College educated smokers were more likely to quit than non-college educated smokers, and they were also more inclined to be influenced by educated smokers who had quit.

So what does all of this mean? That undertaking a difficult task is easier to do with the help of someone you love. Nearly 5 million people die each year around the world from smoking-related causes [source: Harvard Univ]. About one-third of these deaths are due to heart disease and stroke -- not a pleasant way to go out.

If you and a friend, relative or spouse smoke, try quitting together. That buddy you take smoke breaks with at work? Give it a go as a team. It's a radical thought, but you could always step out and enjoy some fresh air together instead.

Related HowStuffWorks Articles

More Great Links


  • "Quitting Smoking Is Contagious." Medical New Today. May 23, 2008.
  • "Smoking Causes Nearly 5 Million Deaths Annually Worldwide." Harvard University. September, 12, 2003. releases/press09122003.html
  • "Smoking cessation is contagious, researchers say." July 14, 2008.
  • "Smoking Is Addictive, But Quitting Is Contagious." Science Daily. May 22, 2008.
  • "Study: Friends help friends kick the habit." Associated Press. May 21, 2008.
  • Christakis, Nicholas A. M.D and Fowler, James H. Ph.D. "The Collective Dynamics of Smoking in a Large Social Network." New England Journal of Medicine. May 22, 2008.
  • Park, Alice. "Quitting Smoking Is Contagious." Time Magazine. May 21, 2008.,8599,1808446,00.html