science of us

Why Having a Best Friend Is Good for Your Health

Photo: Constance Bannister Corp/Getty Images

It’s pretty well-established at this point that having friends is good for you — over the years, study after study has found that social support is a significant predictor of a long, healthy life. The word friend, though, can mean so many things in so many different contexts: your work spouse, the old college pal you call when you feel like reminiscing, that person on the edge of your social circle that you always chat with at parties. Maybe you use “friend” to refer to a broad swath of people you enjoy hanging out with; maybe you reserve it for the few people you’d feel comfortable spilling your guts to.

According to one of the newest studies of the bunch, that last type of friendship may be one of the most valuable when it comes to your well-being: In a paper published last month in the journal Child Development, a team of researchers found that having a childhood best friend can play a significant role in a person’s mental health well into adulthood.

The study drew from a data set that tracked the mental health of 169 racially, ethnically, and socioeconomically diverse adolescent participants at three points: age 15, age 16, and age 25. For the first two rounds, subjects also identified the person they considered to be their best friend, and the study authors interviewed both members of the duo (the label of “best friend” didn’t have to be mutual, the authors noted, and participants didn’t necessarily have to name the same person both years). By age 25, the researchers found, subjects who had had higher-quality close friendships as a teen —defined here as “high degree of attachment, intimate exchange, and support” — tended to have lower social anxiety, an increased sense of self-worth, and fewer symptoms of depression.

“We weren’t surprised that better adolescent close friendships turned out to be important, but we were surprised by just how important they turned out to be into adulthood,” says lead study author Rachel Narr, a doctoral student in psychology at the University of Virginia.

Importantly, it was quality, not quantity, that seemed to matter. In fact, teens who prioritized broader social networks over a few close friends actually had higher rates of social anxiety in young adulthood. When kids are focused on being popular instead of forming deep connections, Narr notes, that’s when problems often arise: “Being the popular kid is ‘cool’ in high school, but by 25, it doesn’t set you apart and make you a leader in the same way,” she says. “The phrase ‘feeling alone in a crowd’ comes to mind when thinking about those kids and their heightened social anxiety later.”

Other researchers have made similar conclusions. Psychologist Tim Kasser, for example, has identified two values that influence how our relationships affect our well-being: popularity, the drive to have more friends and be liked by a wider circle of people; and affinity, the drive to deepen and build close relationships. Much like Narr’s findings, Kasser discovered that those who sought popularity over affinity tended to be less happy, less healthy, and often more depressed. Those who sought and found best friendship, on the other hand, had the opposite outcome.

And in a pair of studies that involved nearly 280,000 individuals, social psychologist Bill Chopik, a professor at Michigan State University, found that the power of friendship gets stronger with age and becomes even more important in fending off loneliness and chronic disease. But, once again, the quality of those friendships matter. “Having closer friends is better than having many, superficial friends,” Chopik says, adding that it’s smart to invest your time and energy in the friendships that make you happiest.

Which, according to both science and common sense, should probably include at least one person whose friendship is deep enough to be considered all-purpose — someone you can go to when you want to cry, vent, brag, laugh. A 2015 paper published in Personality and Social Psychology Review suggests that people generally look to their best friend to fill two critical roles: “source of strength support,” in which friends provide comfort, protection, and soothing; and acting as a “relational catalyst,” challenging, encouraging, and celebrating the other person. A best friendship, in other words, can make the bad better and the good even more so, something that more casual friendships can’t always pull off.

That’s not to say, though, that you can’t reap the benefits of best friendship if you no longer keep in touch with anyone from your younger years. “Great friends are made at all ages,” says Kelly Rudolph, a certified life coach who often writes about relationships.

With a childhood best friend, Rudolph notes, you learn about life together, with all the traumas, challenges, and excitement of growing up — but when you make a best friend later in life, the relationship has a different kind of power thanks to the experience you both bring to the table. “The conversations, support, and adventures can be deeper and more fun,” she says, “as you navigate your future with your combined wisdom.” And all the evidence suggests it’ll be a longer, healthier future, too.

Why Having a Best Friend Is Good for Your Health