A study published in the journal Psychological Medicine provides new evidence that problematic cannabis use may lead to schizophrenia, particularly for young men who are heavy users. The research, likely the largest epidemiological investigation conducted to date that directly focused on the cannabis-psychosis question, delved into Danish health histories from 1972 to 2021. The study examined health records of 6.9 million people and found that up to 30 percent of schizophrenia diagnoses—about 3,000 in total—could have been prevented if men from 21 to 30 years old had not developed cannabis use disorder. Read the article here.