Research says the more intelligent a person is the fewer friends they have — not because they’re difficult to be around, but because the older they get the less willing they become to spend their limited social energy on conversations that go nowhere and people who stay on the surface

I noticed something a few years ago. The older I got, the less interested I became in going to things I didn’t actually want to go to.

Drinks with people I hadn’t seen in years and wouldn’t particularly miss if I didn’t see again. Networking events where everyone was performing enthusiasm. Dinner parties where the conversation never got past house prices and holiday plans.

It wasn’t that I’d become antisocial. If anything, the friendships I did invest in had gotten deeper and more honest. My circle had just gotten smaller. And for a while, I thought there might be something wrong with that.

Turns out, there isn’t. In fact, research suggests it might be a sign of intelligence.

The study that changed how we think about intelligence and friendship

In 2016, evolutionary psychologists Satoshi Kanazawa from the London School of Economics and Norman Li from Singapore Management University published a study in the British Journal of Psychology that turned a common assumption on its head.

Using data from a long-term survey of 15,000 adults aged 18 to 28, they found two broad patterns. First, most people reported higher life satisfaction when they socialised more frequently with friends. No surprise there.

But highly intelligent individuals showed the opposite pattern. The more they socialised with friends, the less satisfied they reported feeling with their lives.

The researchers framed their findings using what they called the “savanna theory of happiness,” which suggests that situations that would have made our hunter-gatherer ancestors happy still tend to make us happy today. Back on the savanna, frequent socialising was essential for survival. But highly intelligent people, the researchers argue, may be better adapted to modern life and less tethered to those ancestral needs. They can find meaning and satisfaction through pursuits that don’t require constant social contact.

It’s not that they dislike people

Let me be clear about something. This isn’t a story about smart people being misanthropic loners who look down on everyone else.

In my experience, the most thoughtful people I know are also some of the warmest. They just have a lower tolerance for conversations that don’t go anywhere. They’d rather spend two hours with one person talking about something real than an evening working a room full of small talk.

I’ve mentioned this before, but I have friends from completely different worlds: corporate, small business, creative. What I value about those friendships is that they all see the world differently to me. What I don’t value is having to pretend I’m interested in a conversation that’s skimming the surface when everyone involved is capable of going deeper.

That distinction matters. Intelligent people don’t avoid connection. They’re selective about where they invest their limited social energy. And there’s a big difference between the two.

Our brains can only handle so many meaningful relationships

Here’s where things get interesting from an evolutionary standpoint.

Professor Robin Dunbar, the Oxford anthropologist behind the famous “Dunbar’s number,” has spent decades studying the limits of human social networks. His research suggests we can maintain roughly 150 meaningful relationships at any given time. But within that 150, there are layers. Only about five people sit in our innermost circle of intimate friendships.

Five.

That’s it. That’s the number of people your brain can manage truly deep, reciprocal, emotionally close relationships with. And we devote about 40% of our available social time to those five people.

When you understand this, the idea that someone with a small social circle is somehow failing starts to look a bit ridiculous. They might just be investing their limited relational bandwidth where it actually counts.

As we age, quality wins over quantity

There’s a theory in psychology called socioemotional selectivity theory, and it predicts exactly what many of us experience as we get older. As our sense of remaining time shrinks, we become more selective about who we spend it with. We prioritise emotional quality over social quantity.

Research published in Frontiers in Psychology, analysing data from nearly 30,000 participants aged 16 to 101, found that the relationship between the number of close friends and life satisfaction weakens with age. For younger adults, having more friends is strongly linked to happiness. For older adults, the number matters far less. What matters is depth.

A separate study from the University of Leeds backed this up, finding that wellbeing among older adults was more closely tied to how people felt about their friendships than how many they had. Older adults had fewer friends on average but interacted with those friends more frequently and more meaningfully.

The courage to let friendships go

Letting people go is one of the hardest things we do. There’s guilt involved, and sometimes grief.

But I think one of the underrated signs of emotional maturity is recognising when a friendship has run its course. Not because anyone did anything wrong, but because you’ve both changed. Or because the relationship has become more obligation than genuine connection.

I lost some friendships over politics in recent years. That was painful. I’ve also let others fade simply because neither of us was getting much from the interaction anymore. That was quieter, but in some ways harder, because there was nobody to blame.

Intelligent people tend to go through this process more consciously. They notice when a relationship has become one-sided. They notice when they’re performing rather than connecting. And eventually, they stop pretending.

Solitude is not the same as loneliness

This is a distinction that our culture struggles with. We’re conditioned to see someone spending time alone as someone who’s missing out. But research consistently shows that intelligent people tend to derive more satisfaction from solitary activities like reading, thinking, and working on personal projects.

That tracks with what I’ve observed in my own life. I write best in the morning, alone, with nothing but coffee and silence. My long walks along the Thames aren’t lonely. They’re when I do my best thinking. The gym isn’t a social event for me. It’s where I go to switch off.

Solitude, chosen deliberately, is restorative. Loneliness is the absence of connection when you want it. The two are not remotely the same, and confusing them leads to a lot of unnecessary worry about people who are doing just fine.

What actually matters

I read something in Robin Dunbar’s work that stuck with me. He said that the single best predictor of your mental health, physical health, and even how long you live is the number and quality of close friendships you have. Not acquaintances. Not social media connections. Close friends.

I discovered in my thirties that male friendships take more effort than I was giving them. I’d let things coast for too long, assuming they’d maintain themselves. They don’t. Relationships need active investment.

But the investment should go to the right places. A handful of people who challenge you, who tell you the truth, who show up when it matters. That’s worth more than a contacts list full of people who’d struggle to remember your birthday.

The bottom line

If your social circle has been shrinking as you’ve gotten older, and you’ve been worrying about what that means, here’s what the research says: it probably means you’re getting wiser about how you spend your time.

Intelligent people don’t have fewer friends because they’re difficult to be around. They have fewer friends because they’ve figured out that depth matters more than breadth. That a good conversation is worth more than a busy calendar. And that the right five people will always beat a hundred acquaintances.

As always, I hope you found some value in this post.

Until next time.