As colder weather takes hold, people everywhere have love on their minds. Downloads of dating apps skyrocket in the period between Thanksgiving and Valentine’s Day. Office workers struggle to concentrate, surreptitiously swiping for someone to cuddle with through the holidays (and beyond).

But what happens once you’re in that relationship you’ve been dreaming of? How do you make it last?

UC Berkeley psychology professor Dacher Keltner has some thoughtful research on the subject. Keltner is an expert on positive emotions, and author of the book Born to Be Good: The Science of a Meaningful Life, which goes into how to be happy in life and in relationships. It’s no wonder, then, that he was also recruited by Pixar to help with the brilliant film Inside Out.

Some of Keltner’s most fascinating research has to do with romantic relationships–and the health of those relationships. And when it comes to relationships lasting, he mentions one skill in particular that couples should hone if they want to go the distance.

You might think it’s communication, or mutual respect. You might think it has to do with having similar values.

Nope. It’s about laughter.

It turns out laughter is a somewhat unexpected yet unnervingly accurate bellwether of relationship health:

“For couples who divorced on average 13.9 years after they were married, it was the absence of laughter that predicted the end of their bond,” stated the research. “In the early stages of a marriage, anger and contempt are highly toxic. In the later phases of intimate relations, it is the dearth of laughter that leads individuals to part ways.”

In other words, you might expect the demise of most relationships to be due to things like fighting over sex and money. But healthy arguing can actually work in your favor. What neverworks in your favor is no more belly laughs. When you stop laughing together, you’re far more likely to split up.

Related to this is the unexpected skill that couples who are more satisfied with their relationships have honed: teasing one another.

That’s right–the research clearly showed that couples who knew how to playfully tease one another were not only happier overall, but were more skilled at handling conflicts (and more likely to stay together).

“[Being playful] helps couples connect, de-stress, and it acts an important repair technique when couples are feeling tense over conflict,” says Julienne Derichs, a licensed marriage and family therapist with Couples Counseling Today. “Laughter and teasing can help de-escalate the conflict and help you remember that you actually like each other.”

This is not license to taunt your partner. Playful teasing does not consist of shaming someone for their deep-seated insecurities. Rather, it’s gently poking fun at personal quirks you find entertaining and endearing.

The right kind of teasing is “sensitive to the other person’s vulnerabilities but shows him or her that you really see him/her, understand his or her quirks and views on the world,” says Dr. Jenn Mann, relationship expert and author of The Relationship Fix.

In other words, it’s not passive aggressive pokes meant to hurt. It’s the playful recognition that your spouse is always losing her keys (but still has the key to your heart).

According to Dacher, playful teasing is so powerful that it’s even a great idea in the middleof an argument: 

“Happy couples tease a lot when they’re in conflict and they tease in these really goofy, lighthearted ways that say, ‘The fact that you don’t do the dishes bothers me, but I still love you. It’s not that big a deal; we can work this out.’ They tease in ways that allow them to express issues of conflict, but in a cooperative and pleasant way. It predicted how long they’d stay together.”

Laughter really is the best medicine. Drink up.

Originally published on Inc.com

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