San Francisco, CA: The passage of adult-use marijuana legalization in California is associated with sustained decreases in alcohol consumption, according to data published in the journal Addiction.
Researchers affiliated with the University of California, San Francisco and the healthcare provider Kaiser Permanente assessed trends in self-reported alcohol consumption among northern Californians prior to and following voters’ decision to legalize marijuana. (California legalized marijuana in 2016.) Study participants were Kaiser Permanente patients who underwent annual screenings for alcohol use during visits with their primary care doctors. Investigators reviewed data from over 3.5 million adults over four years.
Researchers identified sustained declines in participants’ weekly drinking patterns, as well as in how often they engaged in heavy episodic drinking, following legalization. Declines were most pronounced among those ages 35 to 49.
“Specifically, this group showed a significant immediate reduction in frequent HED [heavy episodic drinking], along with gradual declines over time in HED and rates of exceeding both daily and weekly limits,” investigators determined. “This may suggest that cannabis policy changes contributed to a meaningful shift away from higher risk drinking behaviors, potentially reflecting greater substitution effects as compared to younger groups.”
Declines were less pronounced among those ages 21 to 34 and among those 65+.
The study’s authors concluded, “Cannabis policy changes in California, USA, appear to be linked to age-specific changes in alcohol use, with moderate reductions, particularly among middle-aged adults.”
The findings are consistent with those from Canada determining that alcohol sales declined in that country following the adoption of adult-use marijuana legalization.
Survey data published last year in The Harm Reduction Journal found that 60 percent of cannabis consumers acknowledge using it to reduce their alcohol intake.
Full text of the study, “Are cannabis policy changes associated with alcohol use patterns? Evidence from age-group differences based on primary care screening data,” appears in Addiction.