A new study recently published in the Drug and Alcohol Dependence journal is adding to the growing body of research showing that adult-use cannabis legalization does not make adolescents more likely to use or abuse marijuana.
Two researchers from Temple University in Pennsylvania set out to investigate the widespread concern that “recreational marijuana legalization (RML) may lead to increased cannabis use disorder (CUD) among youth due to increased marijuana use.” To test this, researchers looked at annual data from the SAMHSA TEDS-A, a dataset that collects information on adolescents aged 12-17 who have been admitted to drug treatment centers anywhere in the US.
In the study, researchers looked at TEDS-A data from Colorado and Washington collected between 2008 and 2017. Since both of these states began selling recreational cannabis in 2014, the researchers were able to compare the rates of teen marijuana treatment admissions before and after legalization. The admission rates in these two states were also compared to those in other US states that did not legalize adult-use weed during that time frame.
The study authors discovered that “over all states in the analysis, the rate of adolescent treatment admissions for marijuana use declined significantly over the study period... with the mean rate falling nearly in half.” The decline in the rate of admissions was slightly higher in Colorado and Washington than in prohibition states, but this difference was not significant.
“To our knowledge, this is the first study examining the effect of recreational legalization of marijuana in the US on adolescent treatment admissions for marijuana use,” the authors wrote, according to NORML. “Our results indicate that RML in Colorado and Washington was not associated with an increase in treatment admissions. Rather, we observe a substantial decline in admissions rates across US states, with evidence suggesting a greater decline in Colorado/Washington following RML as compared to non-RML states.”
The study makes it clear that teen admissions for cannabis use disorder (CUD) treatment are on the decline, but it does not reveal exactly why this is the case. “While we are encouraged that rates of new treatment admissions for marijuana use among adolescents exhibited a general decline in the states we examined, it is unclear whether this finding reflects trends in the prevalence of CUD or, rather, changes in treatment seeking behaviors due to changing perceptions of risk and public attitudes towards marijuana use,” the authors explain.
Although the exact reasons for this decline are uncertain, one thing does remain clear: Adult-use legalization is not linked to increases in problematic teen cannabis use.
Dozens of other studies also show similar conclusions. Early studies from Colorado, Washington, and Oregon found that teen pot use rates declined after each state legalized adult-use sales. Last year, more studies found that adolescent cannabis use was continuing to decline or stay constant in RML states. And just last week, a study reported that Uruguay's decision to become the first country to legalize weed in 2013 had no impact on teen cannabis use, even though weed is fairly accessible to most teens.