6 Reasons Your Friends Are Good for Your Health

BFFs Michelle Williams and Busy PhillipsBFFs Michelle Williams and Busy PhillipsApril Daniels Hussar, SELF magazine

Have you called your bestie today? You should -- just to say thanks! Because in addition to being good for your spirit (and your need to have company when you Facebook-stalk your ex-boyfriend!), your girlfriends are literally healthy for you!

"Having good friends improves your health and your longevity," psychologist Irene Levine, Ph.D., a professor at NYU Medical School and author of Best Friends Forever, tells HealthySELF. Today just happens to be National Girlfriends Day, so here are six of Levine's top reasons to celebrate those awesome women in your life:

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1. Good friends improve your health.
According to Levine, "There have been many studies that show an association between good health and friendship." To start, says Levine, good friends encourage you in healthy lifestyles. Indeed, as SELF has previously reported, women who work out with a BFF are 45 percent more likely to exercise than those who sweat solo, and spend 40 percent more time exercising!

2. Girlfriends tell it straight. Good friends encourage you in what Levine calls "help-seeking." When you're going through something serious, a real BFF will encourage you to seek out help, whether it's with a mental health professional, a doctor or through another support system. Tough bestie love!

3. Good friends are stress-busters.
This may be one of the reasons why friends have been shown to improve your health physiologically, says Levine, referencing findings from a UCLA study showing that a woman's "social nature" reduces her risk of disease and lowers her blood pressure, heart rate and cholesterol.

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4. BFFs can save your life!
Good friends enhance your ability to cope with illness, says Levine, pointing to research that shows how important having close friends is to women battling breast cancer. "Not just for logistical reasons but also for the emotional reasons -- not feeling like you're alone," Levine says, noting that the 2006 Nurses' Health Study found that women with a network of intimate family and friends were more likely to survive breast cancer, while socially isolated women were five times more likely to die from it.

5. Girlfriends help you find your place in the world.
"Women look to other women to help define our sense of self," says Levine. As a child, you start with looking to your family (moms, aunts, sisters, etc.), but then, she says, "Friends open up a whole new world to you, in terms of pursuing interests and careers, even figuring out your sense of style." In this way, friends help you feel connected and encourage your independence, says Levine -- something that continues all though your life, with old and new friends alike. Speaking of new friends ...

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6. Making new friends is good for you, too!
Spending time with friends you've had for a long time is great; for one thing, it's meaningful to spend time with someone who has a shared history with you, says Levine. But fostering new friendships is also good for you. "Don't make the mistake of thinking you can't make new friends, or that everyone already has their friends," she says. New pals, says Levine, may help you develop new interests and open new experiences for you. "It's nice to have a balance of some old friends and some new friends," she says.

A final note to all you Facebook fiends: "Technology is wonderful and has really enriched a lot of people's friendships; it allows people to reconnect and to stay connected even when friends live many miles away," Levine says. However, she adds, online friendships are not a substitute for the joys of spending time in person with your bestie. "Seeing their facial expressions, the sounds of their voice -- face time really helps!"

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