New research links excessive marijuana use in young men to schizophrenia

Young men who smoke a lot of marijuana increase their chances of schizophrenia, according to a new study. Researchers analyzed the health records of six million people over five decades. They found strong evidence of an association between cannabis use disorder (CUD) and schizophrenia among both men and women, but the link was much stronger in young men. In fact, researchers believe as many as 30% of schizophrenia cases among men ages 21-30 could have been caused by CUD.

It can be difficult to distinguish between enjoying weed and suffering from cannabis use disorder. According to the CDC, a person who is unable to stop using marijuana even though it’s causing health and social problems has CUD. Around 30 percent of marijuana smokers have CUD.

This research comes at a time when weed use has dramatically increased in America. According to a recent Gallup poll, 16% of Americans say they smoke marijuana and almost half of the population say they’ve tried it at least once.

The study found that the proportion of new schizophrenia cases that could be linked to CUD has also increased over the past five decades. The researchers say that is likely because more people struggle with CUD, and cannabis is also becoming more potent.

The study, which was led by researchers at the Mental Health Services in the Capital Region of Denmark and the National Institute of Drug Abuse, was recently published in the journal Psychological Medicine.