Last fall, as a freshman newly arrived at North Greenville University, I was in a lecture hall, bored and scrolling on my phone, when something pulled me away: One of my football teammates was furiously tapping buttons on his phone. What was he doing?

It turned out he was placing a $200 wager on an NBA game that night. As an 18-year-old, he uses his own debit card to regularly place bets—and he’s not the only one. On my campus, especially among many of my teammates, guys have become obsessed with online sports betting, sometimes spiraling into debt.

What starts out as a seemingly harmless diversion quickly becomes a trap. I’ve had friends who have lost hundreds, lied to their families and pulled away from the team, all while chasing the rush of a winning bet that may never arrive. Sports gambling was a major problem for many of my high-school classmates, but it’s gotten even worse in college. Now, as March Madness ramps up this weekend, when wagering and betting pools are everywhere, the opportunities to get sucked into gambling apps will only increase.

Today’s college sports culture makes betting feel like a rite of passage, and platforms like FanDuel, PrizePicks and BetMGM make it all too easy to pick up the habit. Although the legal gambling age is 18 in a handful of states, the American Gaming Association, which represents the major betting platforms, requires that 73.6% of the audience for ad campaigns be 21 or older, and it prohibits marketing on college campuses.

But when my peers see the app’s slick marketing campaigns, the pull is undeniable, with celebrity-endorsed ads hyping the thrill of a quick win on TikTok and Instagram in the run-up to nearly every sporting event.

I’ve watched friends score a few wins on smaller bets only to go on to bigger wagers and then lose it all. During last year’s March Madness, one was down more than $500 and had to come clean to his family because he’d used a card linked to their accounts. His parents grounded him and cut off support for a while. After that, he didn’t hang out with us as much, saying he was embarrassed after the losses.

Once young men figure out a way around the age-verification process—whether by using a VPN or a parent or older relative’s bank information—they can quickly wipe out any savings from jobs or allowances.

I have one friend who used money from a part-time job to bet on NBA games. Once that was gone, he got desperate and started using a family member’s linked account, burning through $600 before they caught on. Another teammate convinced his parents to allow him to make a $50 bet for “fun.” After losing, he secretly used a shared credit card to try to try to recoup his losses. Another friend ended up selling his gaming console and a pair of shoes to cover a $500 bet that didn’t pan out.

The social fallout can be tough, with the heaviest bettors sometimes ghosting friends entirely. One guy who used to be the life of our group chat went quiet as he got caught up in tracking his bets. Others struggle with academic classes, staying up late glued to the apps and skipping homework.

Why is betting so popular among guys my age? It’s partly how we think. Our brains struggle to deal with the consequences of a $200 bet or a $400 loss. Pamela Brenner-Davis, leader of the New York Council on Problem Gambling, warns that younger brains are not developed enough to handle the addictive nature of gambling. “Near wins” also exploit this vulnerability by activating our brain’s rewards system almost as strongly as a win, making losses feel like progress and encouraging us to keep betting.

And when we do win, the rush of adrenaline can feel like a drug. The betting apps know how to capitalize on this, advertising “free bet” offers and same-day payouts. On top of this, celebrities and influencers make sports betting look like a fast track to a new car or a Rolex. Friends will brag about wins and how much money they are supposedly making. One told me that when he saw a DraftKings ad during an NBA game he thought, “It must be OK if Kevin Hart is doing it.”

What can we do to solve the problem? Parents need to talk to their kids—not just about setting reasonable limits for how much financial loss is tolerable, but about how to resist the temptation to bet in the first place.

My friends are good kids. They’re just chasing an experience and don’t fully understand the consequences. I’ve bet small amounts before, and at the time it didn’t feel serious. But that’s the problem. High schools should teach about the dangers of gambling in the same way they talk about drugs and alcohol, and not just for how it impacts our finances, but for the damage it can do to our lives.

The cautionary tales aren’t far-off stories. They’re warnings about what’s happening to young men right now. And I don’t want to watch another friend sell his stuff or lie to his family. Because sports betting isn’t just harmless fun; it’s about guys my age risking their futures, one bet at a time.