A bold reality check: adolescent cannabis use is linked to a noticeably higher chance of developing serious mental health conditions later on. That’s the central finding of a large new study published in JAMA Health Forum, which followed 463,396 teens aged 13 to 17 through their mid-20s. The researchers found that cannabis use in the past year during adolescence was associated with roughly twice the risk of newly diagnosed psychotic disorders, bipolar disorder, as well as depressive and anxiety disorders by young adulthood. The study was conducted by teams at Kaiser Permanente, the Public Health Institute’s Getting it Right from the Start, the University of California, San Francisco, and the University of Southern California, with funding from the NIH’s National Institute on Drug Abuse (R01DA0531920).
Using electronic health record data from routine pediatric visits between 2016 and 2023, the researchers observed that cannabis use tended to precede psychiatric diagnoses by about 1.7 to 2.3 years. The longitudinal design strengthens the case that adolescent cannabis exposure may be a risk factor for later mental illness, rather than a consequence of emerging psychiatric symptoms.
As cannabis products grow stronger and are marketed more aggressively, the study suggests that adolescent cannabis use is tied to a doubling of risk for psychotic and bipolar disorders—two of the most serious mental health conditions. The authors call for an urgent public health response: reduce product potency, emphasize prevention, limit youth exposure and marketing, and treat adolescent cannabis use as a significant health issue rather than a harmless habit.
Quote: Lynn Silver, M.D., program director of Getting it Right from the Start and study co-author, emphasizes the importance of providing parents and teens with accurate, evidence-based information about the risks involved.
Cannabis remains the most commonly used illicit drug among U.S. teens. Monitoring the Future data show use climbs with grade level—from about 8% of 8th graders to 26% of 12th graders. The 2024 National Survey on Drug Use and Health reports that more than 10% of U.S. youths aged 12 to 17 used cannabis in the past year. Meanwhile, average THC levels in California cannabis flower exceed 20%, with concentrates reaching over 95% THC, highlighting how potency has surged over recent years.
Unlike many earlier studies, this research did not focus solely on heavy or problematic cannabis use. Instead, it examined any self-reported past-year use based on universal screening of teens during standard pediatric care, offering a broader view of exposure and associated risks.
Related perspectives discuss broader trends and potential interventions, including how legalization might influence use patterns, and the potential of digital programs to reduce harm among young people.
Key takeaway from the researchers: even after adjusting for prior mental health conditions and other substance use, adolescent cannabis users showed a substantially higher risk of developing psychiatric disorders—especially psychotic and bipolar conditions. The study’s lead author, Kelly Young-Wolff, Ph.D., notes that this adds to the growing evidence that adolescent cannabis exposure can have long-term health consequences, underscoring the need for reliable, evidence-based information for families.
The study also identified higher cannabis use among teens enrolled in Medicaid and those living in more socioeconomically deprived neighborhoods, raising concerns that commercialization could widen existing mental health disparities.
Source: Young-Wolff, K. C., et al. (2026). Adolescent Cannabis Use and Risk of Psychotic, Bipolar, Depressive, and Anxiety Disorders. JAMA Health Forum. DOI: 10.1001/jamahealthforum.2025.6839. https://jamanetwork.com/journals/jama-health-forum/fullarticle/2845356
Note: For medical questions or concerns, consult a healthcare professional. This summary is informational and not medical advice.
