States with Adult-Use Pot Saw Decrease in Alcohol Use, No Increase in Teen Substance Abuse

Legislation to legalize adult-use cannabis, as well as an increase in retail sales in Canada and the U.S. did not lead to an overall increase in teen substance abuse, a team of researchers found. They also found that adult-use legislation led to a “modest decrease” in teen alcohol and e-cigarette use.

The research was led by co-principal investigators Lynch School of Education and Human Development professor Rebekah Levine Coley, School of Social Work Professor Summer Sherburne Hawkins, and Economics Department Chair Christopher F. Baum. They believe they are among the first to evaluate associations between adult-use cannabis legislation and recreational cannabis retail sales through 2021, and teen substance abuse. Naoka Carey, a doctoral candidate in the Applied Developmental and Educational Psychology department of the Lynch School, as well as Claudia Kruzik, a postdoctoral research associate at the University of Maryland-College Park, also contributed to the study.

The cross-sectional study is entitled “Recreational Cannabis Legalization, Retail Sales, and Adolescent Substance Use Through 2021,” and was published online and in JAMA Pediatrics on April 15. Researchers used survey datasets to evaluate adult-use cannabis legalization and retail sales policies, as well as adolescent substance use through 2021.

Adult-use cannabis legalization was associated with modest decreases in cannabis, alcohol, and e-cigarette use, while retail sales were associated with lower e-cigarette use, and a lower likelihood, but also increased frequency of cannabis use among youth consumers, essentially canceling out and leading to “no overall change in cannabis use.”

They found no evidence suggesting otherwise, as the dust settles from 24 states and Washington, D.C. enacting adult-use cannabis legislation, and 18 states implementing adult-use cannabis sales.

The Findings Show Effects of Adult-Use Cannabis Legalization

Researchers wanted to sort through perceived effects of cannabis legalization to determine if it indeed leads to an increase in substance abuse, but didn’t find a link. 

 “Although studies of early-enacting states and Canada reported few effects of recreational cannabis legislation on adolescent substance abuse, experts have highlighted the need to further assess policy outcomes in youth as legislation and retail availability spread, and other policies targeting youth substance use shift,” the authors said. “We found limited associations between recreational cannabis legalization and retail sales with adolescent substance use, extending previous findings.”

Overall however, since findings were mixed, with data showing a lower likelihood of cannabis use despite increased frequency, it shows no increase in teen substance use. They also arrived at other conclusions regarding adult-use cannabis’s impact on alcohol use, and e-cigarette use that are worth noting.

“According to the researchers,” an April 18 announcement reads, “recreational cannabis legalization was associated with modest decreases in cannabis, alcohol, and e-cigarette use, while retail sales were associated with lower e-cigarette use, and a lower likelihood, but also increased frequency of cannabis use among youth consumers, leading to no overall change in cannabis use.”

The findings show that there wasn’t a substantial increase in teen substance use overall.

“The results suggest that legalization and greater control over cannabis markets have not facilitated adolescents’ entry into substance use,” noted the study co-authors.

Other Studies Show No Link Between Adult-Use Cannabis and 

The study aligns for the most part with previous data showing no link between legalization and increased drug abuse. A previous study also found an increase in cannabis use but lower rates of alcohol abuse, with no overall increase in substance abuse disorders.

Researchers published a study, “Recreational cannabis legalization has had limited effects on a wide range of adult psychiatric and psychosocial outcomes,” via  Cambridge University Press on Jan. 5. In it, researchers sought to “quantify possible causal effects of recreational cannabis legalization on substance use, substance use disorder, and psychosocial functioning, and whether vulnerable individuals are more susceptible to the effects of cannabis legalization than others.”

Living in a legal state was “not associated” with substance abuse disorders, although they found it led to higher pot use but lower alcohol use. Living in a legal state was associated, in fact, with lower alcohol use disorder (AUD) rates.

“In the co-twin control design accounting for earlier cannabis frequency and alcohol use disorder (AUD) symptoms respectively, the twin living in a recreational state used cannabis on average more often, and had fewer AUD symptoms than their co-twin living in an non-recreational state. Cannabis legalization was associated with no other adverse outcome in the co-twin design, including cannabis use disorder. No risk factor significantly interacted with legalization status to predict any outcome.”

The findings mount as experts determine the impact of adult-use cannabis policy, laws, and retail sales on public health in multiple states.