Earlier this week, the world watched as 19-year-old Olympic swimmer Caeleb Dressel broke down in tears after Team USA snagged the gold in the men’s 4×100-meter freestyle relay. Seeing Michael Phelps console him was a moment of raw tenderness; something that reminded us all of what it means to be human.

Dressel, along with teammate Ryan Held, aren’t the only athletes who’ve shed tears of joy at this year’s Olympic games in Rio. This got us thinking about the phenomenon that is happy crying. At one point or another, we’ve all been moved to tears by moments of sheer happiness. Whether it’s setting eyes on your newborn for the very first time, walking down the aisle on your wedding day, or feeling overwhelmed by awe-inspiring natural beauty, emotionally powerful moments often render us weepy and vulnerable.

“Emotional tears are unique to humans; we’re the only ones who do it,” says crying expert Robert Provine, a professor of psychology and neuroscience at the University of Maryland, Baltimore County.

According to Provine, who wrote the book Curious Behavior: Yawning, Laughing, Hiccuping, and Beyond, humans actually produce three different types of tears.

Basal tears: These basically serve to keep the eyes lubricated and functioning properly. They also have antibiotic properties to help fight infection. “These tears have an agent that’s rather like penicillin,” says Provine.

Tears of irritation: Exactly what the name implies, these are the tears we shed when an irritant enters the equation (think cutting onions or getting splashed with something that agitates the eye).

Tears of emotion: Any number of emotional situations—happy, sad, angry or otherwise—can trigger the waterworks. What’s perhaps even more interesting is that, when put under a microscope, emotional tears look quite different than the other two. Smithsonian.com reports that they even contain distinct hormones thought to have natural pain-relieving properties. This makes sense in relation to tears of grief or sadness, but it’s less clear why they’re present in tears of joy. In fact, experts seem split as to why the body produces emotionally induced tears at all.

Provine believes it’s actually an evolutionary behavior that’s directly linked to the emergence of humans as a social species.

“What we’re dealing with is a very broadly focused social signal, and I believe it’s associated with the recent evolution of emotional tears,” says Provine, who speculates that emotional crying is relatively new for our species. “What we’re seeing is what a behavior looks like when evolution is sort of in full flight. If you came back in 100,000 years and looked at this, you might find that emotional tears are specific to sadness.”

Could it be that happy crying is simply the result of an evolutionary behavior that’s still ironing out its kinks?


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Other experts argue that reacting negatively (crying) to a positive situation (winning a gold medal) may be a way in which the body calms itself so that it can better process overpoweringly good news. For instance, Yale psychologist Oriana Aragón suggests that playfully aggressive behavior—like the urge to pinch a baby’s cheeks—might ultimately help us simmer down when emotions are high.

“We have the first evidence that these negative expressions may help in regulating overwhelming positive emotions,” she told Scientific American last year.

Aragón was referring to a series of studies in which people were shown images of babies, then asked to share how they naturally wanted to interact them. What they found was that “cuter” babies were more likely to elicit a playfully aggressive response from participants. But what’s interesting here is that the people who did react this way also appeared to calm down and become more emotionally regulated quicker than those who didn’t.

To extrapolate this out a bit, happy crying might help bring us back to center so that we’re better equipped to digest what’s happening and make more sound decisions. This stands apart from other experts who link emotional crying to feelings of helplessness. Following this line of reasoning, emotional tears are nothing more than a knee-jerk response to uncertainty when in a situation that’s beyond our control.

While the specifics of why we cry when happy remain unclear, Provine acknowledges that it may indirectly elicit empathy from others. “If we examine the evolution of tears, I think the first step was tears associated with sickness, like an individual with red, inflamed, teary eyes,” he says. “These pathology-based tears would solicit caregiving from others.”

He believes that it has evolved in the sense that now, emotional tears—which are not associated with sickness—are enough on their own to solicit concern and care from other people. (This might explain why Michael Phelps felt compelled to comfort his teammates while on the Olympic podium.)

Either way, we’ll likely be seeing more happy tears from Rio in the coming weeks.

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