Surfers pee in their wetsuits. I’ve never met one who doesn’t. All those people you see out there in the ocean, looking calm and free? They are. They’re peeing.

This is not a subject surfers talk about much. But they have always seemed to be comfortable in this territory otherwise reserved for children, the infirm, and the terrified.

When I recently raised the topic among fellow surfers, they seemed delighted to get to speak openly about it. Listening to my friends’ confidential tones, I realized this may be one of those subjects that, residing in the whispered shadows, bonds us in its weirdness.

It’s impractical not to pee in your suit.

“You’re not going to get out of the water, take your wetsuit off, and pee,” says Emma Doyle, a Wellfleet surfer. “That’s a 45-minute endeavor.”

Getting out to the surf through breaking waves can be a significant struggle. Taking off and putting on a wetsuit is a process. Everyone I asked thought that getting out of the water was unrealistic and unnecessary.

There’s something else about it, though. I heard it first from my nonsurfer mother, Sharyn Lindsay. “It’s an elemental thing to pee in the water,” she said. Little kids do it all the time, she pointed out. “As soon as they hit the water, they just unload.”

It’s natural.

Being in water does seem to make humans have to pee. Admit it: you’ve felt the urge yourself. Apparently, peeing in the ocean is not something just surfers do. Swimmers and beach-sitters likely also indulge.

“Everyone pees in the ocean, don’t they?” asked Amy Ramsdell, a Wellfleet beachgoer, without a second’s hesitation when I asked for her thoughts on wetsuit-peeing. Caitie Phillbrook, a visitor from Washington state agreed. After all, she said, “You’re in water.”

It’s practical. It’s natural. And everyone else is doing it.

The ocean offers one thing other bodies of water don’t: dilution. The fact that there is a massive body of water there to wash away your sins makes this social transgression feel justified. “It’s like pissing your pants while you’re in the washing machine.” That’s Emma, again.

The American Chemical Society has addressed this question. Its answer, in “To Pee or Not to Pee?,” published in 2013 in Chemical & Engineering News, is “It’s okay to go in the ocean.”

I asked the flame-haired Justin O’Connor, local surfer, actor, and all around wonderful human, why he pees in his wetsuit. He responded with enthusiasm: “It’s not healthy to hold in pee.” Not that he pushes, he said. “I just let it flow.”

Surfers tend toward the superstitious.

You can’t pee and surf at the same time. So, surfers will tell you it’s well known that, as soon as you start to pee, a good wave, or even a whole set of good waves will come. I can say, from definitive research, that there is an absolute scientific relationship between wave size, wave frequency, and peeing. In fact, I’d say it goes beyond correlation and enters the realm of causation. At least my loss will be someone else’s gain.

In the end, whatever the reasons, there is some small satisfaction that comes with breaking rules that don’t really matter. Though it can take some time for new surfers to indulge.

I spoke with Chelsea Peck, a beginning surfer, to get the perspective of a newcomer.

“Justin told me it’s OK to pee in my wetsuit and that everyone does it,” she said, but at first she couldn’t let loose. “It’s not because I’m grossed out by urine,” she said. “I’m a nurse, and I have touched other people’s urine more than my own in my lifetime.”

It’s just that she had not fully entered the subculture of surfing.

By now, she admitted, “I’ve peed in my suit twice so far and both times were — satisfying, if I’m being honest. It was nice to warm up.”

Surfing has its own set of values and ethics. And, in the way of other subcultures, its own rules that satisfy the needs and expectations of the art.

“In the water, it’s the opposite of on land,” Emma Doyle explained. “If you pee yourself on land, you’re the outlier. Out there in the water, if you don’t pee yourself, you’re the outlier.”

There is togetherness in this — an experience that bonds us in groupness. Isn’t this what culture and society is? We share openly in the bright experiences of our achievements, our goodness, beauty, love, and strength. But, in the tribes we choose to be a part of, are we not equally bonded in the things we don’t often speak of — our losses, our darkness, shame, and weakness?