One key to a long life, is healthy friendships. Meaningful friendships are one of the common factors in the world’s Blue Zones, where people often live to 100 or older. Indeed, our friendships become more important than our family relationships as we age so it’s important to invest wisely. But how exactly? Dr. Marisa G. Franco, author of Platonic: How The Science of Attachment Can Help You Make—and Keep—Friends, has some ideas.

Quality over quantity

As we get older, we naturally tend to focus less on having a large quantity of friends and more on having high-quality connections.

“By quality, I mean relationships where you feel like you matter, you feel authentic and there’s reciprocity,” explains Franco. “Both people are considering their needs and the other person’s needs at the same time. As people focus on more quality connections, they end up being happier.”

If you want to be happier in your friendships, Franco encourages you to be intentional about who you spend time with and ensure you’re bringing out the best in each other. These will be friendships where you feel most like your true self and there’s a mutual investment.

Talk through conflict

If you’ve ever quietly quit a friendship, then you may tense up at the thought of sharing your true feelings with a friend. While conflict is unavoidable, it doesn’t have to be a death sentence when it comes to your relationships.

“A lot of times in friendship, it ends because we don’t make the unsaid said and it tends to hover over us to where this issue that may have seemed small makes us more disengaged or withdrawn around friends,” says Franco.

But before you run down a list of all your friend’s wrongs, Franco reminds us that it’s not just about bringing up issues, it’s about doing so in an intentional way.

“You always need to be kind toward your friend, even when you’re in conflict,” she says. “So you could frame it as, ‘hey, you mean a lot to me and this has been on my mind. I didn’t want it to create distance between us, so that’s why I’m bringing this up.’”

In an ideal scenario, you’re able to give your friend a heads up that there’s an important issue you’d like to discuss so they’re not caught off guard. It’s also important that you’re open to any feedback your friend may have to share with you as well.

Express your affection

On the flip side, don’t hesitate to give and receive affection when it comes to friends as doing so can help foster a lasting, meaningful bond.

“Sharing with our friends how much we love and value them is actually good for us and when we’re affectionate and vulnerable with our friends, that helps us feel closer, too,” says Franco. “Friendships can help decrease our blood pressure and cholesterol and there’s a study that says having a confidant is the number-one thing that is preventive against depression. So your friends can literally save your life.”

Learn more about all things crypto with short, easy-to-read lesson cards. Click here for Fortune’s Crypto Crash Course.



Original: Fortune | FORTUNE: If you want to live longer, try being a better friend. Here’s how