rethinkTHC Search
Menu
Study breakdown

The Link Between Teen Cannabis Use and Mental Health Has Grown Stronger Over 15 Years

LongitudinalStrong evidence
The takeaway

Among French teens, the association between regular cannabis use and mental health problems like suicidal thoughts and antidepressant use has roughly doubled from 2008 to 2022, even as overall teen cannabis use declined.

Parents of teens, school counselors, adolescent health providers, and policymakers concerned about youth cannabis use trends.

What the researchers found

The association between regular cannabis use and suicidal ideation in 17-year-olds increased from OR 1.44 in 2008 to OR 2.52 in 2022, while the association with antidepressant use rose from OR 2.57 to OR 4.47 over the same period.

Why it matters

Even though fewer teens are using cannabis today, those who do appear to face substantially higher mental health risks than teen users did 15 years ago — possibly due to higher THC potency or self-selection of more vulnerable individuals into use.

The numbers in context

Regular cannabis use fell from 7.4% (2008) to 3.8% (2022). Suicidal ideation rose from 16% to 18%. The cannabis–suicidal ideation association nearly doubled (OR 1.44 → 2.52). The cannabis–antidepressant association nearly doubled (OR 2.57 → 4.47).

How the study worked

Researchers analyzed five waves of a nationally representative French survey of 17-year-olds (over 150,000 total participants) from 2008 to 2022, using multivariable models adjusted for gender and socioeconomic variables.

What this study cannot tell us

Cross-sectional survey waves cannot establish causation. The study cannot distinguish whether stronger associations reflect higher THC potency, self-selection of vulnerable teens, or other unmeasured factors. Data are from France and may not generalize.

How to read the evidence

Large nationally representative sample (150,000+ participants) across five survey waves spanning 15 years, with consistent statistical adjustments.

When this study was published

Published 2025, analyzing data from 2008–2022.

The bigger picture

This study challenges the assumption that declining teen cannabis rates automatically mean declining harm. As cannabis products become more potent, the remaining users may represent a higher-risk group, and the per-user risk appears to be increasing.

Questions still open

  • Is the rising association driven by increased THC potency in available products? Are today's teen cannabis users a more psychologically vulnerable subset? Would similar trends appear in countries with different cannabis policies?

Common questions

Does this mean cannabis causes suicidal thoughts in teens?
The study shows an association, not causation. The strengthening link could reflect higher THC potency, self-selection of more vulnerable teens into cannabis use, or other changing social factors.
Why is the association getting stronger if fewer teens use cannabis?
Researchers suggest that as casual users decline, remaining users may be a more vulnerable group with preexisting mental health risks, and/or that higher-potency products now available may increase harm.

Read the original research

Cannabis and mental health in adolescents: changes in associations over 15 years.

Social psychiatry and psychiatric epidemiology, 60(7), 1649-1658

Citation

Valter, R; Nezet, O Le; Obradovic, I; Spilka, S; Falissard, B; Josseran, L; Gautier, S; Airagnes, G. (2025). Cannabis and mental health in adolescents: changes in associations over 15 years.. Social psychiatry and psychiatric epidemiology, 60(7), 1649-1658. https://doi.org/10.1007/s00127-025-02859-7

Explore the wider topic