Is happiness contagious?

Is happiness contagious? Two Harvard researchers, Nicholas Christakis and James Fowler, believe the answer to that question is a resounding YES! based on their exhaustive analysis of data from the Framingham heart study of fifteen thousand people. Christakis and Fowler meticulously traced family and friendship links between the Framingham study subjects and found perceived closeness strongly correlated with health habits. For example, if a person’s co-workers quit smoking, the person is likely to do the same. If close friends/family of the same gender become obese, a person is likely to follow suit.

Christakis and Fowler believe that emotional mirroring (I want to be like that person) and peer pressure explain the correlations, interpreting social networks as a causal factor in human behavior. “People are connected, and so their health is connected,” they conclude.

Critics contend that the study highlights correlation rather than causation. Homophily (wanting to be with like people) and environment provide two better explanations of the health commonalities among friends and family.

To defend their work, Christakis and Fowler analyzed data from five hundred pairs of twins. That data supported their contention that social networking directly effects one’s health, for better or worse. Furthermore, they argue based on that additional research that perhaps as much as half of a person’s connectedness to others is a function of genes; highly connected people removed from one network tend to gravitate toward the center of another network. Changing behavior by understanding the influence of connectivity is thus not easily done, especially among people who tend to be loners. (Clive Thompson, “Is Happiness Catching?” New York Times, September 12, 2009)

The conclusions of Christakis and Fowler’s research dovetail with the research that shows people who are active in a religious organization tend to be healthier than people who are not involved in religion (click here or here to link to my blog on some of that research). Most religious communities constitute affirming, mutually supportive networks in which people seek to develop and to sustain healthy lifestyles. Religion generally promotes an optimistic view of life.

Two important implications emerge from their research. First, people who wish to develop or to sustain a healthy lifestyle should actively cultivate relationships with healthy, optimistic people. Second, one practical way to love one’s neighbors is to encourage them to develop and to sustain relationships with healthy people.