The Power of Social Circles

We all know that laughter is contagious. But what about healthy lifestyle habits? They’re infectious too. And people’s social networks—whether in person or online—can have a tremendous effect on well-being.

Take Calgary office manager Deanna Johnston’s goal to lose weight. She joined a local weight-loss support group and went to regular meetings.

Strangers became friends. Surrounding herself with others who had a similar goal made all the difference. Other people’s desire to lose weight rubbed off on her: she’s lost more than 30 pounds.

“I had lots of support, and I felt like every accomplishment was applauded, small or large,” Johnston says. “There was never any judgment. People who’ve gone through the same thing know what the emotional and physical challenges are like.”

Social connections can save

Alex White knows the value of strong social connections too. A graduate of Montana State University, White was diagnosed with bipolar disorder in his teens. He attempted suicide before gaining control of the illness.

He went on to help develop a website that provides young adults with help for such issues as mental health, relationships, and campus life. By connecting with others online, users end up being completely honest about their experiences, forging new relationships, and providing mutual encouragement along the way.

“I would not be alive today if it had not been for the love, care, and support I received from family, friends, and loved ones,” White says. “StrengthofUs.org is about helping and inspiring each other.”

Research supports health benefits

More and more, scientists and scholars are looking at the evidence behind the kinds of claims that Johnston and White make about the health benefits of social circles.

“Social networks have value precisely because they can help us to achieve what we could not achieve on our own,” explain Harvard Medical School internist and social scientist Nicholas Christakis and University of California at San Diego political science professor James Fowler in the book Connected: The Surprising Power of Our Social Networks and How They Shape Our Lives. (Little, Brown and Company, 2009).

“Students with studious roommates become more studious. Diners sitting next to heavy eaters eat more food. Homeowners with neighbours who garden wind up with manicured lawns. And this simple tendency for one person to influence another has tremendous consequences.”

The notion that personal behaviours rub off on people around us is so promising that it’s being investigated in relation to some of today’s most pressing health concerns.

Smoking

According to QuitNow, an online resource for British Columbians wanting to stop smoking, chances of success are far greater when smokers connect with others who’ve already kicked the habit or are in the process of doing so.

A 2008 study in the New England Journal of Medicine showed that stop-smoking efforts do indeed spread via social connections. Based on the more than 12,000 people who were part of the groundbreaking Framingham Heart Study and assessed between 1971 and 2003, the study found that smoking cessation by a spouse decreased a person’s chances of smoking by 67 percent. Meanwhile, cessation by a friend or co-worker lowered the chances by about 35 percent, and cessation by a sibling reduced the chances by 25 percent.

Weight and fitness

Social connections seem to affect physical fitness, according to economist Scott Carrell of University of California-Davis. Carrell headed a recent study into the spread of fitness habits of more than 3,000 students at the United States Air Force Academy who were monitored between 2001 and 2005.

Researchers concluded that if half of one person’s friends became out of shape, his or her chances of failing the course’s basic fitness requirements tripled.

“In equilibrium, our estimates imply that each out-of-shape individual creates two additional out-of-shape individuals through their social interactions, thus supporting the provocative notion that poor physical fitness spreads on a person-to-person basis,” the researchers wrote.

A 2007 study in the New England Journal of Medicine found that a person’s chances of becoming obese increased by 57 percent if he had a friend who became obese. Among adult siblings, if one became obese, the chance that another would too increased by 40 percent. And if a spouse became obese, the likelihood that the other partner would also gain excess weight increased by 37 percent.

Mental health

Depression appears to be contagious too. A 2010 study in the journal Molecular Psychiatry examined whether depressive symptoms in one person were associated with similar signs in friends, co-workers, siblings, spouses, and neighbours.

It found that people were 93 percent more likely to be depressed if a person they were directly connected to (at one degree of separation) was depressed. People at two degrees of separation (the friend of a friend) were 43 percent more likely to be depressed, while people at three degrees of separation (the friend of a friend of a friend) were 37 percent more likely.

“At four degrees of separation the effect disappears,” the authors noted, “a result that is in line with other results that have shown similar drop-offs after three degrees of separation, including obesity, smoking, happiness, and loneliness.”

Being surrounded by peers who can relate to specific mental-health conditions is proving to be an effective component of treatment.

The Journal of Psychiatric Services in 2008 found that support from trained peers helped people with mental illnesses address certain attitudes, values, and behaviours more effectively in some cases than advice from health professionals.

The bigger picture

By identifying how certain conditions and behaviours can spread via social networks, the potential exists to develop health policies and preventive measures that reach far and wide.

In the meantime, it’s worth considering the impact of your friends on your health—and your impact on theirs.