By TARA PARKER-POPE


In the quest for better health, many people turn to doctors, self-help books or herbal supplements. But they overlook a powerful weapon that could help them fight illness and depression, speed recovery, slow aging and prolong life: their friends.

Researchers are only now starting to pay attention to the importance of friendship and social networks in overall health. A 10-year Australian study found that older people with a large circle of friends were 22 percent less likely to die during the study period than those with fewer friends. And last year, Harvard University researchers reported that strong social ties could promote brain health as we age.

“In general, the role of friendship in our lives isn’t terribly well appreciated,”said Rebecca G.Adams, a professor of sociology at the University of North Carolina, Greensboro.“There is just scads of stuff on families and marriage, but very little on friendship. It baffles me. Friendship has a bigger impact on our psychological well-being than family relationships.”

In a new book, “The Girls From Ames: A Story of Women and a 40-Year Friendship,” Jeffrey Zaslow tells the story of 11 childhood friends who scattered from Iowa to eight different states. Despite the distance, their friendships endured through college and marriage, divorce and other crises, including the death of one of the women in her 20s.

Two of the friends have recently learned they have breast cancer. Kelly Zwagerman, now a high school teacher who lives in Northfield, Minnesota, said that when she got her diagnosis in September 2007, her doctor told her to surround herself with loved ones. Instead, she reached out to her childhood friends, even though they lived far away.

“The first people I told were the women from Ames,”she said.“I e-mailed them. I immediately had e-mails and phone calls and messages of support. It was instant that the love poured in from all of them.
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In 2006, a study of nearly 3,000 nurses with breast cancer found that women without close friends were four times as likely to die from the disease as women with 10 or more friends. And notably, proximity and the amount of contact with a friend wasn’t associated with survival. Just having friends was protective.

Bella DePaulo, a visiting psychology professor at the University of California, Santa Barbara, whose work focuses on single people and friendships, notes that in many studies, friendship has an even greater effect on health than a spouse or family member.

Exactly why friendship has such a big effect isn’t entirely clear. It may be that people with strong social ties also have better access to health services and care. Beyond that, however, friendship clearly has a profound psychological effect.

“People with stronger friendship networks feel like there is someone they can turn to,”said Karen A.Roberto, director of the center for gerontology at Virginia Tech university.“Friendship is an undervalued resource. The consistent message of these studies is that friends make your life better.”