Humans are inherently social creatures. We know this. Looking at our species through an evolutionary lens, we tend to talk about our need for social connection as it relates to survival. Our ancestors needed to work in teams to hunt, collect water and firewood, build shelters, rear young, keep watch for predators, and all the other business of staying alive. While that’s undoubtedly true, our need for affiliation runs much deeper than those practical concerns. Our health and well-being quite literally depend on having strong social bonds with others.
Even when our survival is assured thanks to safe housing, easy access to clean water and plentiful food, medical care, and financial security, lonely or socially isolated individuals are likely to die sooner. On the flip side, a robust social support network is associated with better physical and mental health outcomes and longer lives.
Friends, it turns out, have a profound impact on health and longevity. Of course, it’s not just about the number of years we have but how we spend them, and good friends also make our lives more enjoyable in countless ways.
Are Good Friends a Key to Longevity and Healthspan?
There’s no doubt that social integration and social support are associated with greater health and longevity, while the opposite, social isolation and loneliness, significantly increase mortality risk. In a 2010 meta-analysis covering 148 studies and 308,849 participants, the researchers concluded that individuals with strong social ties were 50 percent more likely to survive compared to those with weak social networks.1 When the researchers looked only at studies with more in-depth measurements of social connectedness, that number jumped to 90 percent. Participants who reported being less lonely similarly enjoyed a 47 percent survival advantage.
Your social network includes partners, children, extended family, neighbors, coworkers, clergy, even your favorite barista or librarian, but friends are special. Friendships are voluntary (unlike family), mutual (unlike children or your boss, with whom equality and reciprocity are not expected), and, for close friends at least, intimate (unlike coworkers or neighbors, probably).
Good friendships are built on liking and mutual respect, and the best friends bring out the best in you. It’s obvious how friends help you live better, but how might they help you live longer?
Friends May Encourage Healthy Habits
Much of the research on social influence and healthy (or unhealthy) behaviors focuses on adolescents and how peers affect things like diet and exercise choices,23 but it’s not just teens who are influenced by their friends. Adults are more likely to be physically active when they have supportive friends, friends who exercise themselves,4, and friends who double as workout buddies.56 Robust and supportive friendships help people maintain their sobriety.7 Individuals who feel more socially supported may find it easier to manage chronic illnesses like type 2 diabetes.8
It’s not just that friends serve as role models or accountability partners, making sure we stick to our resolutions, although they do. Nor do friends merely provide practical support (picking up a prescription, watching your kids so you can go to the gym) and emotional support, although they do those things, too. Good friends can also help enhance your sense of self-worth and self-esteem, helping you believe that you deserve to take care of yourself.
Friendships Keep Loneliness at Bay
Loneliness and social isolation are major risk factors for all manner of chronic diseases and death. In some studies, poor social ties are even more detrimental than things like smoking, drinking, and poor metabolic health.910 Many experts believe that loneliness and social isolation should be considered public health issues and that we should invest in public policy initiatives designed to increase social support for people of all ages.
Research suggests that friendships are particularly good at staving off loneliness. For older folks (50+), friendships offer better protection against loneliness than relationships with adult children or other family members.11Despite the stereotype, older people actually aren’t lonelier overall. Loneliness across the lifespan is u-shaped, with middle-aged folks reporting the most. That means that loneliness tends to decrease as we age, compared to when we are mired in the working-and-parenting-teens years.12 (By the way, the same is true for happiness. Data from around the world strongly suggests that happiness is lowest around age 50, and it goes up from there.13)
However, studies of older adults show that loneliness is mediated by health. As health and mobility decline, so does social participation. It becomes harder to get out and see your friends, and some folks may not want to burden their friends with their health problems.1415 This creates a negative feedback loop where individuals increasingly withdraw from their social networks, leading to worse health and increased mortality. On the other hand, if you have friends who encourage you to stay fit and active for as long as possible, you create a positive feedback loop that enhances longevity. So keep moving.
Friends Help You Buffer Stress
One theory of why we evolved to have friends is that intimate friendships promote positive emotions and cooperation, which enhances survival, while close friendships provide material support, social interaction, and protection of mutual interest.16 In other words, friends are there to make life better, more pleasant, and easier.
This rings true, doesn’t it? Think about the last time you laughed really hard with someone. Chances are you were with a good friend. Who would you call in the middle of the night in an emergency? Probably not your boss. It would be your partner or that one friend who you know would come no questions asked. Knowing someone has your back—again, both practically and emotionally—is a huge weight off your shoulders.
The implications go way beyond “it feels good to have friends in your life.” There’s growing evidence that friendships can actually help reduce oxidative stress.
Wait, so you’re saying friends are anti-inflammatory?
Put it in the category of strange but true. In fact, scientists believe this is probably a primary mechanism by which friendships promote health and longevity.17 We know that chronic stress causes inflammation, and chronic inflammation leads to or exacerbates pretty much every health problem you can think of. People who experience more positive emotions typically have lower inflammation, while negative emotions are associated with higher inflammation.1819 Heaps of evidence support the notion that people who have better social relationships and more social support also have lower inflammation.20
So it just makes sense that friends, who offer social support, positive emotional experiences, and stress relief, would help us be healthier and live longer. However, what we get from friends may be less important than what we give. In a longitudinal study of more than 1,500 people in their sixties or older, mortality was significantly lower among people who said they were able to offer support to their friends, relatives, and neighbors.21 In fact, the amount of help they received from their social network didn’t impact mortality at all once the researchers took into account the effect of the help they gave to others.
The act of nurturing our friendships affects us on a physiological level, reducing stress22 and even, yes, inflammation. In one recent study, positive social relationships were associated with lower IL-6, an inflammatory marker, but only for women who said they were able to offer support to their friends and family (results weren’t significant for men).23
If You Want to Be Happier, Make Friends
So says a panel of happiness experts, anyway. Seventeen scholars, researchers, and writers weighed in on the most feasible and effective ways to promote happiness. “Invest in friends and family” topped the list of things individuals can do to increase their personal happiness, while “reduce loneliness” came in at number four on the list of policy suggestions.24
Friendships can be a conduit through which you explore your interests, find new passions, and experience personal growth. I’d argue that friends are uniquely situated for that. Family members often have deeply ingrained beliefs about who you already are or who they want you to be. Your partner hopefully helps you grow and experience the good things in life, but you’re probably also wrapped up in the functional concerns of day-to-day adulting, especially if you’re still working and/or raising kids. The rest of your social network is probably too distant. Friends are where it’s at.
The best friends also challenge your limiting beliefs and negative self-talk, because they see the best in you and reflect it back, and because they truly want to see you flourish. Everyone needs at least one friend who elevates them, like my “idea friend” Suzanne, so-called because she’s always sending me text messages starting with, “So I had an idea…” (I’m her “yes friend” because I always go along with her ideas, no matter how crazy.) My son asked me the other day, “Mom, does Suzanne push you outside your comfort zone?” “No,” I told him, “Suzanne offers me opportunities to step out of my comfort zone, and I choose to take them.” This is important for me because adventure is one of my strongly held personal values. You may instead value contribution, faith, humor, or community. ??Whatever is important to you, find a friend who helps you live in alignment with your values.
How Many Friends Do You Need?
Happiness, loneliness, and perceived social support are all subjective, so it’s hard to say exactly. Some people may be fulfilled with one or two close friends, while others thrive on having a large and diverse social network.25
There’s some evidence that when you’re younger, a larger social network predicts better health outcomes.26 Even among adults, subjective well-being correlates with the number of friends you have. One study even concluded that by doubling the size of your friend group, you increase well-being as much as if you earned 50 percent more money.27
There’s a limit on how many friends we can realistically manage, though. Scholars, including Robin Dunbar of Dunbar’s number fame, conjecture that humans can maintain very intimate relationships with about five people and close relationships with an additional 12 to 15 people. They state:
“In terms of size, the sympathy group (typically 12–15 members)… may represent the group of reliable friends on whom one can depend for a variety of exchange relationships (e.g., friendship in the social sense, protection against harassment, minimizing social stress, distributed childcare, etc.). In contrast, the innermost layer of about 5, the support clique, seems to represent the set of closest intimates, typically immediate family members and best friends, who are most likely to provide a mutual environment for emotional and instrumental (e.g., financial) support.” 28
That said, the quality of your friendships probably matters more than the absolute number. Especially as we age, friendships that cause stress and strain actually undermine health.29
Are Online Friendships Just as Good as IRL?
Ah, the 100,000 dollar question. Twenty years ago, I was a grad student studying whether people could form meaningful connections online. This was cutting-edge research at the time. Social networking was relatively new, and online relationships were still something of a novelty. In the years since, it has become abundantly clear that yes, we can form friendships online. However, even two decades later, the debate about whether those friendships are as “real” as IRL friendships rages on. In the aforementioned study, where doubling your friend network was as good as money, that was only for real-world friendships. Having a larger online circle didn’t help. If anything, it was associated with somewhat poorer subjective well-being.
Don’t disinvest from your online friendships just yet, though. We simply don’t know how online friendships affect health (especially in old age) and longevity. Moreover, there may well be generational differences between today’s older folks, who didn’t grow up using the Internet to build and maintain relationships, and Gen Z’ers for whom online friendships have always been a way of life.
What to Do if You Want to Live Longer
Make friends with happy people.
Happiness spreads among friends, even more than within families,30 and happier people tend to live longer on average.3132 Surround yourself with happy people, and you’ll catch the happiness bug, too.
Choose friends who challenge you.
I’m not sure this one is entirely science-backed, but it just makes sense to choose friends who don’t allow you to stagnate and succumb to the forces of entropy. Surround yourself with people who keep you on your toes with stimulating conversation and new ideas, experiences, and perspectives. Ideally, have at least one friend who helps you stay active.
Find ways to be there for your friends.
Take opportunities to offer social support, whether it’s a sympathetic ear, a shoulder to cry on, helping with errands, or whatever you know will take some stress off your friends’ plates.
Let your friends be there for you.
Open yourself up to receiving social support, as well. Remember that your friends benefit from helping you, so accepting their kindness helps them, too.
Build a social network that suits your needs.
In other words, make as many friends as it takes for you to feel not-lonely. Take the time to invest in a few close friendships, and pad your network with other friends and friendly acquaintances based on what makes you feel most satisfied and supported.
But focus on quality over quantity.
For all the benefits that friendships can deliver, poor quality relationships, such as those characterized by competition or toxic behaviors, can lead to poorer health outcomes.33
Lindsay Taylor, Ph.D., is a senior writer and community manager for Primal Nutrition, a certified Primal Health Coach, and the co-author of three keto cookbooks.
As a writer for Mark’s Daily Apple and the leader of the thriving Keto Reset and Primal Endurance communities, Lindsay’s job is to help people learn the whats, whys, and hows of leading a health-focused life. Before joining the Primal team, she earned her master’s and Ph.D. in Social and Personality Psychology from the University of California, Berkeley, where she also worked as a researcher and instructor.
Lindsay lives in Northern California with her husband and two sports-obsessed sons. In her free time, she enjoys ultra running, triathlon, camping, and game nights. Follow along on Instagram @theusefuldish as Lindsay attempts to juggle work, family, and endurance training, all while maintaining a healthy balance and, most of all, having fun in life.