Frequent Non-medical Cannabis Use and Mental Health: A Cross-sectional Analysis Prior to Regulated Access

Abstract As more countries explore regulatory models for non-medical cannabis, concerns persist about its mental health impact. While frequent use has been linked to depression and anxiety, the strength and direction of these associations remain uncertain. This study presents baseline data from Züri Can , a longitudinal observational study in Zurich, Switzerland, evaluating cannabis access under a strictly regulated framework. We conducted a cross-sectional analysis of 2207 participants who completed assessments prior to purchasing cannabis. Mental health was assessed using the PHQ-9 and GAD-7, and substance use with the CUDIT-R and AUDIT-C. Despite high cannabis use (56.4% ≥ 4 days/week) and 24.5% meeting criteria for cannabis use disorder, the prevalence of depression (2.8%) and anxiety (1.7%) was lower than in the general population. Mixed-model analyses indicated modest positive associations between cannabis use and symptoms of depression and anxiety, whereas alcohol, other illicit substances, prescription medication, female gender, and lower income showed similar or stronger positive associations. These findings suggest that mental health risks among frequent users may not primarily manifest as mood disorders but as substance use disorders and highlight the value of screening procedures in regulated cannabis frameworks.