Smile, and your friend's friend smiles, too
December 05, 2008
Health Reporter
The whole world might not smile with you. But your happiness is remarkably contagious and can be felt by strangers up to three degrees of separation away, a large new Harvard University study says.
Your joy, like a rock dropped in the water, sends out ripples of well-being that have measurable impacts on the contentment of other people, even your friends' friends' friends, says Dr. Nicholas Christakis, a professor of medical sociology at Harvard and the lead study author.
"It's not that we've shown that emotions spread from person to person. We kind of knew that already," says Christakis, whose paper appeared yesterday in the British Medical Journal.
"What's interesting is that emotions spread from person to person to person, and from person to person to person to person."
And the feeling that spreads most vigorously is happiness, says Christakis, who calls the phenomenon an "emotional stampede."
He says our social networks, which bind diffuse individuals in a vast cloth of communications, is replete with emotions and that your feelings are measurably dependent on those of perfect strangers.
"It's a quilt and there's little patches. And some of them are happy patches and some of them are unhappy patches," he says. "And whether or not you're happy depends not just on what you choose to do, your own choices and actions and thoughts, but also on which patch you happen to occupy."
The study, which looked at 5,000 people over two decades, suggests having a happy friend can increase your probability of contentment by some 15 per cent.
That contagion remains robust far down the line, with your happiness increasing by a significant six per cent the chances of someone being joyful at three degrees of separation.
The paper used data gathered by the huge and ongoing Framingham Heart Study – begun in 1948 – which includes data on emotional states that are relevant to cardiovascular health. It also took such thing as economic well-being, social status and education into account before making its findings.