09/15/2008 05:12 am ET Updated Nov 17, 2011

Why Friendship Is Good For Your Health

"You got to have friends to make that day last long," sings Bette Midler. But good friends may help your life last longer, too, according to an Australian study. Conducted by the Centre for Ageing Studies at Flinders University, the study followed nearly 1,500 older people for 10 years. It found that those who had a large network of friends outlived those with the fewest friends by 22 percent.

Why is this so? The authors suspect that good friends discourage unhealthy behaviors such as smoking and heavy drinking. And the companionship provided by friends may ward off depression, boost self-esteem and provide support. Also, as people age, they may become more selective in their choice of friends, so they spend more time with people they like.

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