Cannabis use among American teenagers is associated with adverse effects on academic performance, impulse control and emotional well-being, according to research published in the journal Pediatrics.
Researchers examined data from 162,532 US students in grades 8, 10 and 12, finding that 26.2% had used cannabis. Among users, 4.6% consumed near-daily, 3.6% weekly, 4.8% monthly, and 13.2% were non-current users.
The study, which analysed data from the Monitoring the Future surveys conducted between 2018 and 2022, revealed dose-dependent relationships between frequency of use and negative outcomes. Even monthly users showed significantly higher odds of poor academic performance compared to non-users, with adjusted odds ratios ranging from 1.30 to 2.20.
The research team, from Columbia University Vagelos College of Physicians and Surgeons, found that the effects extended beyond academics. Monthly and non-current users also demonstrated greater odds of poor impulse control and self-regulation (adjusted odds ratios of 1.26–2.19) and adverse emotional states (adjusted odds ratios of 1.1–1.42).
The study authors also observed a consistent dose-response pattern across all adverse psychosocial categories, with one exception – low social engagement showed minimal association with cannabis use frequency.
Younger adolescents, particularly those under 16 years of age, appeared especially vulnerable to the academic and emotional impacts of cannabis use, the study said.

The effect sizes varied by category: small for poor academic performance, small to medium for poor impulse control and self-regulation, and small for adverse emotional states.
The cross-sectional study involved a racially and ethnically diverse sample with a mean age of 16 years, of which 45.8% were male.
The researchers concluded that their findings underscore the importance of healthcare providers routinely enquiring about cannabis use in adolescent patients, noting that adverse associations were evident even among those using cannabis as infrequently as once per month.
Whilst the findings highlight the risks associated with adolescent cannabis use, international evidence suggests that legalisation and regulation may actually help protect young people. In Germany, youth cannabis consumption amongst 12 to 17-year-olds declined from 6.7% to 6.1% between 2023 and 2025 following legalisation in April 2024, with regular use dropping from 1.3% to 1.1%. Similarly, Canadian government reports showed youth usage rates have not risen since legalisation in 2018, whilst analysis of US states with legal cannabis markets found that teenage consumption either remained stable or declined in most jurisdictions. These data support the argument that regulatory frameworks reduce young people’s access to unregulated products while enabling better education about potential harms, suggesting that concerns about increased youth access under legalisation may be unfounded.

