The Lancet Psychiatry | March 19, 2019

A landmark study published in the Lancet Psychiatry Journal finds that daily use of high potency marijuana is linked to greater rates of psychosis in Europe. According to the study, an estimated five in ten new cases of psychosis in Amsterdam and three in ten new cases in London are linked with high potency marijuana use.

The study finds that daily, average potency marijuana users were three times more likely to be diagnosed with first episode psychosis compared to non-users. Daily use of high potency marijuana, increased to five times more likely.

This study is among the first to illustrate the link between marijuana use and the onset of severe mental health issues, like psychosis, at a population level.

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