US: A Panel Study of the Effect of Cannabis Use on Mental Health, Depression and Suicide in the 50 States

Drug Free America Foundation (DFAF) teams up with Johnny’s Ambassadors for first-of-its-kind nationwide study finding teen marijuana use rose and mental health declined in states with legalized marijuana

A first of its kind nationwide study, commissioned by Drug Free America Foundation, Inc. and Johnny’s Ambassadors, finds more youth are using marijuana and experiencing greater mental health implications in states that have legalized marijuana. Compared to states where marijuana is not legalized, marijuana use is higher among all age groups in more highly permissive states, with 47% more monthly marijuana use among adolescents (ages 12-17) and 81% more monthly marijuana use among young adults (ages 18-25) in states with fully legalized recreational marijuana programs.

While marijuana use grew, subsequent raises for major depressive events, severe mental illnesses, and suicidal thoughts all increased in more highly permissive US states. For each 1% increase in overall monthly marijuana use, self-reported major depression increased by 0.45% for adolescents and 0.21% for young adults. For every 1% increase in overall monthly marijuana use by young adults, severe mental illnesses increased by 0.12% and suicidal thoughts increased by 0.11%.

Relevant scholarly literature advises this increase in marijuana use intersects with a dramatic rise in THC potency. Since the 1960s, the average THC potency in marijuana products has increased from 2% during the Woodstock Era to 4% in 1995, 12% in 2012, and over 17% in 2017, with a recent study showing average THC levels over 20% in nine highly permissive states.

This research is significant in that it represents the first nationwide correlative regression data linking monthly marijuana use and self-reported mental health disorders among adolescents and young adults over 51 geographical variations and 8 time periods. This research strongly supports federal and state policy considerations for caps on high potency THC products.

Access the study here