Happiness Is Contagious
Social Networks Affect Mood, Study Shows
Happy Friends Make You Happy
They concluded that the happiness of an immediate social contact increased an individual's chances of becoming happy by 15%, Fowler says.
The happiness of a second-degree contact, such as the spouse of a friend, increases the likeliness of becoming happy by 10%, and the happiness of a third-degree contact -- or the friend of a friend of a friend -- increases the likelihood of becoming happy by 6%.
The association was not seen in fourth-degree contacts (the friends of friends of friends of friends).
Having more friends also increased happiness, but having friends who were happy was a much bigger influence on happiness.
Fowler says the findings do not mean you should avoid unhappy people, but that you should make an effort whenever you can to spread happiness.
"We need to think of happiness as a collective phenomenon," he says. "If I come home in a bad mood, I may be missing an opportunity to make not just my wife and son happy, but their friends."
Richard Suzman, PhD, who directs the behavioral and social research division of the National Institutes of Health, which funded the study, calls the research "pioneering."
"These findings are very strong," Suzman tells WebMD. "From a public policy perspective, this research means we need to consider the societal impact on happiness, or obesity, or smoking. We are only just beginning to understand how social networks influence these things for good or for bad."