The best friendships are truly unfiltered – you feel comfortable telling your best friend things you would never dream of confiding in anyone else. Ever wonder why that is? Science can explain it!
1. Because she offers support, even if she can’t help.
Studies show that people value acceptance and emotional expressiveness over utility in friendship. So even if your best friend can’t solve your problem, it’s helpful to have someone listen to you vent.
2. Because you share the same “social-identity.”
A study of college students showed that while intimacy builds friendships, the surest indicator of a best friend is sharing the same “social-identity”, which can be religion, sports teams, roles like motherhood, or membership in the same club.
3. Because we go the extra mile for them.
Psychologists call this the Ben Franklin Effect: "He that has once done you a kindness will be more ready to do you another than he whom you yourself have obliged." Which is to say, we tend to like someone more after we do something nice for them.
4. Because your friend is comfortable saying anything to you.
Sociologists have found that the key to jumping from being acquaintances to being friends is reciprocal sharing. So as one person reveals deeper information about herself to an acquaintance, the acquaintance reciprocates, and soon they’re sharing everything.
5. Because your friend stays positive.
Disclosure is necessary for intimacy, but the personal revelations can’t be one long string of downers. We’re more likely to work to maintain a friendship if it doesn’t feel draining, so by remembering to look on the bright side and not being a drag, best friends increase their intimacy.
6. Because you hang out with your best friend.
This one may seem obvious, but in the age of virtual interactions it bears repeating: studies show we feel closest to people with whom we spend actual face-to-face time.
7. Because your best friend makes everything seem easier.
One study showed that people reported hills seemed less steep when in the presence of a close friend. Another found lower levels of the stress hormone cortisol present if a negative situation was experienced with a friend. When you’ve got your best friend with you, everything feels manageable, so why wouldn’t you confide in them?
8. Because your best friend doesn’t hold a grudge.
A lot of friendship is about expectations. While it’s important to work to meet those expectations, friendships can’t last unless you cut each other some slack when one person falls short of those expectations. Since you know your best friend won’t judge you forever, you’re more willing to share a secret with them.
9. Because you’re their best friend, too.
Friendship is built not just on reciprocity of intimacy but also reciprocity of value. In other words, we tend to like people who like us back. Studies have found that we tend to give higher ranks to the people who rank us highly when considering friends.
10. Because nonverbal clues tell you your best friend is trustworthy.
Studies show that humans are remarkably good at picking up on nonverbal indications of trustworthiness. By the time someone has become your best friend, you know you can trust her with even your deepest secrets.
11. Because friendship is good for you!
Numerous studies have shown that social support is incredibly important to health late in life and even lowers mortality rates. So go ahead and tell your best friend anything – it may help you live longer!