The Other Gay: Catching Happy :)

When you're smiling, the whole world really does smile with you. At least that's what some new research concludes. Happiness is contagious, and that we pass on our good cheer, even to total strangers. It was previously found that obesity and smoking habits spread socially, as well.

American researchers who tracked more than 4,700 people, as part of a 20-year heart study, also found the transferred happiness is good for up to a year. While the study is another sign of the power of social networks, it ran through 2003, just before the rise of social networking Web sites like Friendster, MySpace and Facebook.

For the study, researchers examined questionnaires that asked people to measure their happiness. They found distinct happy and unhappy clusters significantly bigger than would be expected by chance.

Happy people tended to be at the center of social networks and had many friends who were also happy. Having friends or siblings nearby increased people's chances of being upbeat. Happiness spread outward by three degrees, to the friends of friends of friends. Happy partners and spouses helped, too, but not as much as happy friends of the same gender.

The study estimates that each happy friend boosts your own chances of being happy by 9 percent. Having grumpy friends decreases it by about 7 percent. But it also turns out misery don't love company: Happiness seemed to spread more consistently than unhappiness. But that doesn't mean you should drop your gloomy friends.

Also, according to the research, an extra chunk of money increases your odds of being happy only marginally, notably less than the odds of being happier if you have a happy friend.

Photo: Getty Images

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