Legalization of recreational cannabis linked with increased alcohol drinking, study finds

The increase in alcohol use, recently reported in JAMA Health Forum, suggests that states that legalize recreational cannabis should also consider targeted public health messaging around alcohol and other policy interventions aimed at mitigating problem drinking.

"Recreational cannabis laws have made cannabis legally accessible to nearly half of U.S. adults, but it has been unclear how this affects the use of other substances, such as alcohol," said senior author Coleman Drake, Ph.D., assistant professor in the Department of Health Policy and Management at Pitt Public Health. "It appears that cannabis use increases the probability that people drink, at least in the three years after legalization."

Drake and his team obtained data on alcohol use by more than 4.2 million adults through the Centers for Disease Control and Prevention's annual Behavioral Risk Factor Surveillance System surveys administered from 2010 through 2019 -- at which point 11 states had legalized recreational cannabis.

The survey inquired about any alcohol use, binge drinking and heavy drinking within the last month, and the researchers looked at differences in responses before and after recreational cannabis legalization.

Any drinking -- measured as having "at least one drink of any alcoholic beverage" in the past month -- increased by 1.2 percentage points in the first year after recreational cannabis was legalized, but diminished in the following two years. There was no change in binge or heavy drinking in the overall population.

When the team dove into the data, they found that the increase was driven by adults ages 18 to 24 who had a 3.7 percentage point increase in any drinking. None of the other age groups had a statistically significant increase in any drinking after cannabis legalization.

Demographically, the increase was also associated with men, non-Hispanic whites and people without some college education.

While recreational cannabis legalization was linked to a small increase in alcohol consumption, the team did not find any evidence of sustained effects on binge or heavy drinking. However, Drake noted that cannabis use has nearly doubled over the past decade, and a prior study estimated that, between 2011 and 2015, excessive alcohol use resulted in the death of over 93,000 Americans per year.

"So, it will be important to monitor whether recreational cannabis laws cause increases in drinking over longer periods of time, particularly among younger adults and men," he said.

By zeroing in on the groups of people who may be most likely to increase risky behaviors, such as drinking more while using cannabis, states can proactively engage those communities and look for ways to mitigate risk -- such as through public health campaigns or alcohol tax strategies -- before recreational cannabis laws go into effect, Drake explained.

"In prior work, I found that recreational cannabis laws temporarily reduced opioid-related emergency department visits," Drake said. "So, I would resist characterizations of cannabis legalization as categorically good or bad. We need to learn more about how cannabis legalization affects all substance use, health, and non-health outcomes, such as drug-related arrest rates, work-related injuries and labor market outcomes. Policymakers should try to think through all these costs and benefits as they consider passing recreational cannabis laws."

Additional authors on this study are Vandana Macha, of Pitt; and Rahi Abouk, Ph.D., of William Paterson University in Wayne, N.J.

This research was supported by National Institute on Drug Abuse award K01D1051761.