Happiness can spread like the measles.
That is the conclusion of a study of more than 4,700 people, followed over 20 years, all part of the Framingham Heart Study social network.
This large study finds that happiness can ripple through a cluster of people who may not even know each other.
And happiness can spread through your social circle including your spouse, sibling, or next-door neighbor.
The study is published in the British Medical Journal BMJ and was conducted by medical sociologists or social epidemiologists at Harvard University.
Nicholas A. Christakis, a medical sociologist at Harvard University who helped conduct the study said of happiness, "But it also depends on the choices and actions and experiences of other people, including people to whom you are not directly connected. Happiness is contagious."
The contagious nature of happiness can affect another for as long as a year and is strongest if the social ties live within a mile. Also those people who already had a friendship that was mutual are most affected.
On the opposite side of the coin, unhappiness can spread as well, but the ability to spread to many is not as strong as the emotion of happiness.
For example, take one happy person in a network. The chance that happiness would spread within the network increased between eight and 34 percent. And even people outside that network would feel the effects, though the effect dropped from about 15 to 10 percent to about six percent, reports the Washington Post.
The research echoes previous findings that quitting smoking can permeate social circles as can obesity. This landmark study shows we are not individual entities acting on our own, but social creatures.
Stanley Wasserman, who studies social networks at Indiana University, said: "We've known that one's network ties are important, but we've never looked at anything on this scale. The implications are you can't look at individuals as little entities devoid of their social context."
Martin Seligman, a psychologist at the University of Pennsylvania calls this, “a pathfinding article.”
The findings may help explain why some countries have people who just seem to be happier. Researchers suggest this may be an evolutionary survival tool that leads to better work performance, greater job satisfaction, good family relationships and a more satisfying social life.
“Laughter and singing and smiling, tune the group emotionally,” according to Seligman. They get them on the same wavelength so they can work together more effectively as a group.” #