5 simple ways to be a better friend, according to Harvard experts who have studied relationships for decades

• Scientists have discovered the secret to happiness: close relationships with other people.
• These relationships can benefit your emotional wellbeing — and even help you live longer.

Scientists have discovered the secret to lifelong happiness. But you may not want to hear it.

After 85 years, researchers conducting the world's longest scientific study of happiness have reached one simple conclusion about what makes for a meaningful life: good relationships with other people, forged by frequent, quality contact.

The only problem is that they've also discovered that we're generally bad at making these kinds of connections.

In general, the directors of the multigeneration Harvard Study of Adult Development write in their new book, "The Good Life: Lessons from the world's longest scientific study of happiness," we just "underestimate the beneficial effects of human connection."

And the benefits can be huge. Their research shows that both the frequency and the quality of our contact with other people are two of the major predictors of our own happiness in life. The benefits aren't only emotional — research has shown that good relationships can even help you live a longer, more pain-free life.

"We need others to interact with and to help us, and we flourish when we provide that same connection and support to others," the book says. "This process of giving and receiving is the foundation of a meaningful life."

Here are 5 of their suggestions for fostering connections with others in your life, every day.

1. Talk about what you're struggling with, wherever you are in life

Harvard Study Director and book coauthor Dr. Robert Waldinger stresses it's important to make space in your relationships to talk about your troubles — wherever you're at in life.

"I used to think, 'oh, I'm never gonna complain about my health the way my parents do,'" he told Insider. "But now I find, 'cause I'm getting old, when we're with friends who are our age, we talk a lot about our health, and I don't censor that."

The book identifies 4 different distinct stages of adult life, from adolescence to late life, and unpacks how what we need from each other changes over time.

"We move with our life stage," he said. "Our big concerns change. And it's okay to talk about that, and to be interested in other people's big concerns."

2. Learn about your people

We all want to feel seen and understood, Waldinger said. One of the best ways to help your friends, family, and other social ties feel that connection with you is by getting really inquisitive — no matter how long you've known them.

"We have to allow ourselves to be interested in what the other person is really into," Waldinger said.

This isn't always an easy task. The psychiatry professor remembers when his son was a teenager, and really into Japanese manga comics and graphic novels.

"It looked stupid to me," he said.

By setting his assumptions aside, and channeling a relentless curiosity, Waldinger discovered that there was a reason his son took an interest in the comics.

"What was cool for me was that Manga had themes in it — themes in them that my son was really interested in about identity, and stuff like that."

3. Spend some time giving others your undivided attention

"What I've learned, and the research has shown this, is that we have to be much more intentional about where we're directing our attention," Waldinger said.

He knows it can be tricky, and it can feel like "you have to use a crowbar to wrench your attention away" from a device, a pressing task, or a to-do list.

But the book argues that because our attention is our most precious asset, we must use it — at least sometimes — to focus entirely on others, and on ourselves too.

"Noticing someone is a way of respecting them, paying tribute to the person they are in that exact moment," it says. "And noticing yourself, checking in about how you move through the world, about where you are now and where you would like to be, can help you identify which people and pursuits most need your attention."

4. Reflect on which relationships you'd like to foster

The book isn't advocating that we get deep and personal with every single person we meet throughout the day, or that each technique will work in the same way for every relationship.

"One size does not fit all," Waldinger said.

Instead, he said, fostering social connection is a lifelong process that requires self-reflection, learning who you are and what you really want. First, check in with yourself. He suggests starting out by asking, "Am I as connected to others as I would like to be?"

"And if not, then in what ways — what's kind of lacking for me?"

One exercise the book suggests is drawing up a list of your most essential relationships, from family to friends — as well as others who you interact with day to day, like coworkers, or old friends who you think about but have fallen out of touch.

Next, think about both the quality and the frequency of your interaction - is it an energizing relationship or a depleting one? Frequent or infrequent? The exercise may help you realize areas where you'd like to strengthen a connection, see someone more often, or where a relationship that's depleting — but important — needs some "special attention," as the book suggests.

5. Make connections happen in small ways each day

One of the simplest ways to connect with someone is to ask them out for a coffee, a walk, or a beer to learn more about them or to catch up. This is a trick Waldinger uses often, but even he has had to remind himself to do it.

"Once the kids were launched, I found that I could just work all the time," he said. "What I had to do — because I believed in my own research, I had to start thinking: okay, who do I want to connect with?"

Then, he'd make some small effort to really get to know that person a little better by suggesting an outing, like a coffee or a walk.

Know that your success rate will probably never be 100%, and that's fine.

"See what comes back," he said. "Some people won't reciprocate and that's just natural. Not everybody's gonna come back positively, but many people will."