Various factors feed into psychosis, like stress and personal genetic makeup. Yet there is strong evidence that use of cannabis is leading to significant mental health problems in Europe—the higher the THC level, the worse for mental health.
When THC potency > 10%, there is a fivefold risk of developing psychosis, according to The Lancet, the prestigious journal(s) of the British Medical Association. Yet even less potent strains were found to increase risks threefold.
19 March 2019. Click for article.