In recent years, the prevailing story where college substance use is concerned has been students’ declining alcohol consumption. This trend is, for all intents and purposes, a public health victory. And yet some have wondered if it’s not another sign, like their decreasing in-person socialization, of an overly anxious generation.

The question of cannabis often takes a back seat in this conversation. How, indeed, has the use of college students’ second-favorite drug changed amid a potential swing away from partying? In this case, there’s the legalization of recreational marijuana in 24 states to consider, as well. Is greater accessibility ratcheting up activity, and to what end for wellbeing? The answers may surprise you, as the saying goes, and not least of all because cannabis use is historically misunderstood.

Jason Kilmer, a psychology professor at the University of Washington, is one of the country's leading experts on substance abuse among young adults, including high school and college students. When we met on Zoom to discuss the latest trends in his field, his preferred longitudinal study on the topic had just released its 2025 results. Every year for almost 50 years, Monitoring the Future, led by researchers at the University of Michigan, has been collecting self-reported data about the drug-use habits of U.S. adults aged 19 to 65. 

The latest Monitoring the Future findings on college student cannabis use are notable because, in many ways, they’ve stayed constant — compared to last year, five years ago, even ten years ago. The data show that, despite what may be common perception, most college students are not using cannabis, nor are they using it significantly more than their modern-day predecessors. But just because the majority aren’t users doesn’t mean schools should unsound the alarms, Kilmer says. Also contrary to what some believe, researchers are only becoming more confident in the harm the drug can cause, particularly to developing brains.

Most college students are not using cannabis, nor are they using it significantly more than their modern-day predecessors.

One of the reasons Monitoring the Future is particularly helpful for higher education student affairs practitioners is that it breaks down data by not only age but college students versus non-college students (both one to four years out of high school). In 2025, the percentage of college students who reported using cannabis in the last 30 days was 25.2 percent. For non-college students, that rate was 30.9 percent — and tends to be higher across the board. Monitoring the Future then calculates whether these results differ significantly compared to one, five, and ten years ago. In this case, there were no significant changes in use for either college or non-college students within any time frame.

That lack of significant change also holds true for college and non-college students who reported daily cannabis use (using 20 or more times in the last 30 days). For college students in 2025, the latest daily rate was 5.3 percent. For non-college students, it was more than double: 12.6 percent. 

For Kilmer, the point worth driving home time and again is that, despite what many might think, far from all college students are using cannabis. It was in fact research on misperceived norms related to cannabis that first drew him into this line of study. In 2000, a colleague found that college students who used cannabis most were also more likely to overestimate use among their peers. Frequent users, likely surrounded by friends with similar habits, may struggle to believe that they’re in the minority.

One of the reasons recognizing the tendency to overinflate campus cannabis use is important is because that understanding could inform prevention tactics. An incoming student who incorrectly believes most of her peers use cannabis may be more likely to end up using it herself in an attempt to fit in, Kilmer said. But research suggests by righting the misperceived norm, some people’s real behavior can be changed — that is, in this case, they may reduce their use.

And it is best, medically speaking, for people, and especially young people, to reduce cannabis use. Notions to the contrary, Kilmer imagines, stem from another sneaky, and false, rumor: that cannabis can't be harmful. Weed may be naturally occurring in theory, he said, but that doesn’t make it safe. Since the 70s and 80s, the concentration of T.H.C., the high-inducing component, has soared from around 2 or 3 percent to as high as 30 percent or more. “Science shows it stopped being natural a long time ago,” Kilmer said. 

As for the idea that you can’t overdose on weed, that you can’t become addicted, that you can’t experience withdrawal — none of that is true either, Kilmer emphasized. “It's never been a question to researchers. We're always struck by the fact: How did that message even get out there?” he said of the confusion. When he worked in student life, he remembered an undergraduate coming in and admitting he was worried he was addicted to weed. He wanted to know “if that's even a thing” because “my roommates keep telling me it's not." 

The risks of cannabis use to young minds include links to mood disorders, attentional issues, and psychosis. Scientists are typically cautious about using the word “causal” to describe the relationship between any two variables. “This is a topic where we get to use the word causal,” Kilmer said. “High-potency cannabis causes psychosis.” Some people end up in an unfortunate cycle, where they think cannabis is helping them with issues like poor sleep, appetite, or anxiety, but in reality those are just the symptoms of cannabis withdrawal. So when they use more, the symptoms go away. Confidently diagnosing cannabis users with A.D.H.D. has become almost impossible, Kilmer added, because the drug’s effects can so closely mimic the disorder.

“This is a topic where we get to use the word causal. High-potency cannabis causes psychosis.”

As the executive director of Student Wellbeing at Boston University, Carrie Landa, a psychologist, is attentive to the ways larger social trends among college students may be affecting substance use habits. The fact that the rate of alcohol use is down, and weed use is stable, could be promising, she said. But she warns against focusing on how much they’re using at the risk of looking past the why of it all. In years past, she’s perceived people getting high in social settings, among friends. But now, she said, “with the current generation who is really facing struggles related to interpersonal connection without technology,” she worries use is often a mode of “self-medicating.” Young people may be using weed to target sleep or anxiety issues — ones that may or may not be connected to cannabis use in the first place. 

So perhaps social anxiety is at play in influencing student usage trends for cannabis and alcohol, even if the former is stable while the latter has gone down significantly (from 63.5 percent in 2015 to 52 percent in 2025). But it’s hard to say for sure. Kilmer said new research on the relationship between cannabis and alcohol use on campus could help clarify some of these "why" questions. In the early 2000s, he said, it was generally accepted that smokers also drank but drinkers didn’t necessarily smoke. Today, he awaits more updated information breaking down the “venn diagram” between different substances among college students. What if, for example, the smokers today don’t also drink?

What is clear to Kilmer is that alcohol and cannabis prevention efforts in colleges should remain a priority. Alcohol is still the most prevalent drug, and the effects of cannabis seem increasingly worrisome. Cannabis users may see the fallout in the classroom, too. In one study, the frequency of marijuana use among students was associated with skipping more classes, lower first-semester G.P.A., and taking longer to graduate. “Now that research has caught up, it really has told a very consistent story,” Kilmer said. “This is a substance worth taking seriously. It's a substance that has very clear implications for mental health and wellbeing, student success.”

The continuing challenge, Kilmer added, is how to influence student behavior. Motivational interviewing has been a successful tactic in one-on-one treatment scenarios, he said. He also encourages university counseling departments to screen for cannabis use disorder. Perpetually, Kilmer is asking himself: “How do we get that science off the page of journals and out there in a way that actually has an impact?”

You can reach LearningWell Reporter Mollie Ames at mames@learningwellmag.org with comments, ideas, or tips.