Your bestie does even more for you than you think.

Jacqueline Andriakos
January 14, 2016

Research has long shown that friendship is essential for your physical and mental well-being. Having a social network can lengthen your lifespan, help you stay slim, and keep your brain healthy as you get older.

But now picture that one friend (or two, or three, if you're lucky) you can send selfies to even when your face is polka-dotted with acne medication, or the pal you reserve the dancing-girls emoji for. Perhaps even the headline made her pop into your head. Yep, she's your bestie–and the closeness you share as a duo comes with its own list of surprising health benefits.

"I call those close friendships emotional health clubs, the gyms for our souls," says Shasta Nelson, author of Frientimacy: How to Deepen Friendships for Lifelong Health and Happiness ($14; amazon.com).

But what makes a bestie a bestie? "These types of deep friendships are where we get to be the most vulnerable, where we get to practice being the best versions of ourselves, and sometimes even the worst versions," explains Nelson. Here are even more unbelievable perks that'll have you running to go hug your No. 1 pal.

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She makes you more optimistic

Your closest girlfriends make hills in your path look smaller, just knowing they're standing beside you help tackle it.

We're not speaking figuratively. In 2008, researchers asked a group of University of Virginia students to stand at the bottom of a hill wearing a heavy backpack. They were then asked to estimate the steepness of the hill in front of them, either while standing alone or with a friend. Those who stood with a friend rated the hill as less steep than students who were alone. But there's more: The longer participants knew their friends, the less steep they estimated the hill to be, too.

She helps block out anxiety

Cue The Beatles' "With a Little Help From My Friends." Not only do close friends help you work through your stress, they may actually help protect your body from stress better than when you try to handle it solo.

James Coan, PhD, associate professor of clinical psychology at the University of Virginia, studied women using MRI brain scans to witness the difference in anxiety levels right before they were jolted with an electric shock alone, or while holding the hand of a close companion. The result? Every participant's scan showed that the parts of the brain that sense danger were much less active when they gripped a pal's hand.

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"The burden of life's many stressors, when you have to deal with them by yourself, not only does it feel more exhausting, it literally creates more wear on your body," Coan explained to CBS News.

She gives you physical and emotional strength

Your confidant may be a better emotional resource than a family member, says a 2014 study, published in Health Psychology.

The researchers followed nearly 750 adults, who were mostly older women, for 12 years to assess the power of friendship in keeping one's health from deteriorating after losing a spouse. Over the course of the study, they looked at the physical health differences between those who lost a spouse and had a close confidant and people who suffered the loss and only had familial support. They learned that having support from relatives didn't have the same positive health benefits, like feeling less depressed, that were associated with having close friends.

So why does a best friend provide an even better shoulder to cry on than, say, a sister or mom? Friendships are discretionary, while family relationships are obligatory in nature, lead study author Jamila Bookwala, a psychology professor at Lafayette College, explained in a press release. She added that in family relationships, you may feel close with the person, but also bothered by them.

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Nelson agrees: "Family members, even children or spouses, often add a lot more stress by default. They come with more logistics, whether it's chores or errands. Your best friend, you don't have to schedule her doctor's appointments or know what she wants for lunch," she jokes. "You get the benefits of friendship often times without a large amount of external stressors and responsibilities."

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