Association of Recreational Cannabis Legalization With Alcohol Use Among Adults in the US, 2010 to 2019
Original investigation
Overview
As of August 2022, 38 US states have implemented medical cannabis laws, 19 of which also legalized so called “recreational” cannabis. These “recreational cannabis laws” (RCLs) have commercialized cannabis and made it accessible to approximately half of adults in the US. Cannabis commercialization has resulted in a 25% increase in cannabis use by adults.
Previous studies investigating the relationship between cannabis and alcohol use have found mixed evidence. Some studies have found that alcohol and cannabis are economic complements – meaning that demand for one increases along with the other. Other studies suggest that the two are substitutes.
In this study, researchers examined the association between cannabis legalization and alcohol use among adults in the US from 2010 through 2019 using survey data of more than 4.2 million respondents. During the study period, 10 states and the District of Columbia legalized adult-use cannabis.
A DiD approach (Difference in differences, a statistical technique) was used to estimate the association between cannabis legalization and alcohol use in all 50 states and the District of Columbia from 2010 to 2019. Researchers examined overall associations and subgroup associations by age, sex, race and ethnicity, and education level.
Researchers found that legalization of cannabis was linked with significant increases in alcohol use, indicating that alcohol and cannabis are indeed economic complements.
- Overall ,cannabis legalization was linked with a 0.9 percentage point increase in any alcohol use.
- Among young adults aged 18 to 24, cannabis legalization was associated with a 3.7 percentage point increase in any alcohol use.
- Among men, cannabis legalization was associated with a 0.8 percentage point increase in binge alcohol use.
Subgroup analyses indicated that the study findings were driven by adults aged 18 to 24 years, as well as non-Hispanic White individuals, men, and persons without some college education.
“Overall, these findings suggest that increased alcohol use among young adults and men may be an unintended consequence of cannabis legalization.”
Macha V, Abouk R, Drake C. Association of Recreational Cannabis Legalization With Alcohol Use Among Adults in the US, 2010 to 2019. JAMA Health Forum. 2022;3(11):e224069. doi:10.1001/jamahealthforum.2022.4069
Abstract
Importance
In the US, cannabis use has nearly doubled during the past decade, in part because states have implemented so-called “recreational” cannabis laws (RCLs). However, it is unclear how legalization of adult-use cannabis may affect alcohol consumption.
Objective
To estimate the association between implementation of state RCLs and alcohol use among adults in the US.
Design, Settings, and Participants
This was a cross-sectional study of 4.2 million individuals who responded to the Behavioral Risk Factor Surveillance System in 2010 to 2019. A difference-in-differences approach with demographic and policy controls was used to estimate the association between RCLs and alcohol use, overall and by age, sex, race and ethnicity, and educational level. Data analyses were performed from June 2021 to March 2022.
Exposures
States with RCLs, as reported by the RAND−University of Southern California Schaeffer Opioid Policy Tools and Information Center.
Main Outcomes and Measures
Past-month alcohol use, binge alcohol use, and heavy alcohol use.
Results
Of 4.2 million respondents (median age group, 50-64 years; 2,476,984 [51.7%] women; 2,978,467 [58.3%] non-Hispanic White individuals) in 2010 through 2019, 321,921 individuals lived in state-years with so-called “recreational” cannabis laws.
Commercialized cannabis laws were associated with a 0.9 percentage point increase in any alcohol use but were not significantly associated with binge or heavy alcohol use.
Increases in any alcohol use were primarily among younger adults (18-24 years) and men, as well as among non-Hispanic White respondents and people without any college education.
A 1.4 percentage point increase in binge alcohol use was also observed among men, although this association diminished over time.
Conclusions and Relevance
This cross-sectional study and difference-in-differences analysis found that recreational cannabis laws in the US may be linked with increased alcohol use, primarily among younger adults and men.
