High potency cannabis, especially when used daily, is "strongly linked" to the risk of developing psychotic disorders such as schizophrenia and paranoia, scientists said Wednesday.
In Amsterdam and London—where high-THC marijuana has long been the rule rather than the exception—50 and 30 percent of new psychosis cases, respectively, were associated with potent forms of the drug.
The findings, reported The Lancet, bolster a growing body of research connecting pot to a range of mental health disorders.
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If high-THC cannabis—including strains such as "trainwreck", "gorilla glue", and "hindu kush"—were no longer available, "12 percent of cases of first-episode psychosis could be prevented across Europe," the researchers calculated.
As an aside, by "strongly linked", it seems that THC can expose/trigger existing mental illness. No one has demonstrated that THC can induce psychosis/schizophrenia in an otherwise healthy person.