From Stranger to Strong Tie: The Science (and Art) of Adult Friendship

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Hi there, it’s Thomas.

We all remember how easy it seemed to make friends as kids. You sat next to someone in class, played the same games at recess, and, just like that (snaps fingers), you were bonded for years. Adulthood, on the other hand, tends to put friendship on the back burner.

But here’s the truth: as we grow older, our social well-being doesn’t just impact how we feel, it profoundly shapes how long and how well we live.

In fact, a study by sociologist Gerald Mollenhorst found that we cycle out roughly half of our close social circle every seven years, largely due to changes in geography, work, family, and routine. Add to that the chronic busyness of modern adulthood, and it’s no wonder so many people report feeling more socially isolated than ever, even when surrounded by others.

And yet, investing in diverse, meaningful relationships is one of the most powerful things you can do to strengthen your resilience, brain health, and overall longevity.

The Science Is Clear: Diverse Social Networks Protect Your Health

Researchers like Julianne Holt-Lunstad (Brigham Young University) have shown that strong social integration is one of the top predictors of longevity, even outranking exercise and quitting smoking in some models. But it’s not just about having people in your life: it’s about the quality and diversity of your ties.

A landmark study published in PNAS (2022) highlighted that people with a broader range of social roles—friend, colleague, mentor, neighbor, teammate—experience less chronic inflammation and better immune responses. These “weak tie” and “medium-strength” relationships buffer against life stress and cognitive decline, especially in later decades.

Simply put: your network is your health plan. But unlike a benefits package, you have to design and maintain it yourself.

Why Adult Friendship Feels Harder — and Why It’s Worth the Effort

“Making and maintaining friendships as an adult, let alone a BFF, can be super challenging,” says therapist Layne Baker. “You aren’t making that up, and you aren’t ‘doing it wrong’ if it’s difficult.”

Why is it harder now than when we were younger?

• Fewer shared environments. Classrooms, dorms, and clubs used to give us built-in face time with peers. That proximity made bonding easier.

• Greater emotional risk. As adults, we’re more guarded. We fear rejection, or worse, indifference.

• Cultural pressure to prioritize romance or work. Adult friendships are rarely portrayed as central, but research shows they are.

Psychologist William Rawlins calls this “the friendship paradox.” We crave deep connection, but we lack social scripts for initiating and sustaining adult friendships. Yet these relationships can be just as vital and intimate as romantic ones, and often more enduring.

So how do we bridge the gap from stranger to acquaintance, from acquaintance to friend, and from friend to inner circle? Here’s what the research, and lived experience, suggest.

More on how to go from strangers to acquaintances after a word from this week’s sponsor.

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From Hello to Belonging: How to Build Adult Friendships

1. Stretch Your Comfort Zone (and Go First)

New friendships require vulnerability. That means asking someone for coffee. Accepting an invite that feels random. Texting first. It may feel awkward, but that’s how relationships begin.

One example: when my friend Shannon moved to LA, she reached out to a woman she’d met online for brunch. That led to an unexpected invite to Disneyland with total strangers. She went anyway. Today, those “strangers” are among Shannon’s closest friends.

Putting it into action: Ask one person this week to grab a quick coffee or walk, even if you’re unsure where it will go.

2. Leverage Your Existing Routines

You don’t need to overhaul your calendar. Instead, look for relational opportunities in your current life: the colleague you laugh with in Slack, the dog owner you always nod to on walks, the barista you chat with at the same coffeeshop.

Veterinarian Sabrina Kong met one of her best adult friends at a dog park, simply by following their dogs’ lead. What started with small talk became weekly walks and then deep life conversations, all without feeling “networky” or forced.

Putting it into action: Start a conversation with someone you already see regularly. Ask a curious question.

3. Create Shared Rituals (Not Just One-Offs)

Repetition is the soil in which friendship grows. Joining a book club, running group, or monthly dinner crew creates predictable, low-pressure opportunities to connect and build shared history.

Whether it’s a hobby, a cause, or even a virtual meetup, consistency is the magic ingredient.

Putting it into action: Join (or create) something that meets monthly or weekly and aligns with your interests.

4. Activate Dormant Ties and Alumni Networks

You don’t have to start from scratch. You already know hundreds, maybe thousands, of people through school, past jobs, communities, or family. Many of them are just one message away from reconnecting.

Alumni groups, old project teams, or even shared social scenes are fertile ground for renewed connection.

Putting it into action: Scroll through your contacts. Who’s someone you used to like but haven’t talked to in a while? Send a “Hey, was just thinking of you…” note.

5. Practice “Friendship Generosity.”

Introduce your friends to each other. Share circles. Invite people along. And let go of “friend possessiveness,” the idea that a good friend can only be yours.

Sociologist Mark Granovetter’s classic work on “The Strength of Weak Ties” shows that it’s often friends of friends who unlock new opportunities and ideas. Expanding your circle expands your perspective.

Putting it into action: Host a casual gathering and encourage each person to bring one other person you don’t know.

Keeping Friends in Orbit

Starting is only half the equation. Sustaining adult friendship requires intention.

• Mini check-ins matter. A quick text, funny meme, or article share can maintain warmth between longer catch-ups.

• Show up for the boring stuff. Friendships thrive not only on fun but on consistency. Be the one who remembers birthdays, asks about the job interview, or follows up after a hard week.

• Be curious. Listen generously. Ask about their world — and then stay present in the answer.

As therapist Sonica Beckmann puts it, “The best friendships grow from consistency and honesty, not perfection.”

This Week’s Challenge: The Acquaintance Accelerator

This week, choose one person in your outer orbit, someone you already kind of know, and take one small step toward deepening that relationship.

It could be:

• Sending a note of appreciation

• Sharing something meaningful

• Inviting them to something casual

Keep it low-stakes. Keep it real. Keep it consistent.

And remember: you’re not just building friendships, you’re investing in the health and resilience of your future self.

Your future you will thank you.

What’s been your experience making friends as an adult? Do you have something you think could help others? Just hit reply. Your email goes straight to my inbox and could go into a future newsletter.

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