A new international review indicates that the commercial sale of cannabis correlates with increased rates of usage and psychosis. The study, analyzing policy shifts between 2000 and 2025, found no similar increase linked to decriminalization or strict regulation of cannabis possession. Researchers examined changes in cannabis use, potency, and mental health outcomes following policy changes across various countries. The findings suggest that making cannabis commercially available leads to a rise in the number of people using the drug. This increase in usage is accompanied by a corresponding rise in reported cases of psychosis. The research highlights a distinction between policy approaches, indicating commercialization presents different public health implications than decriminalization or regulated access. Further investigation is needed to fully understand the long-term effects of commercial cannabis sales.