Two new studies look at the impact of legalizing cannabis on the recreational habits of college students; they show that increased cannabis use can lead to a reduction in binge drinking.
As of January 2020, 33 US states have legalized cannabis use for medical purposes while 11 and Washington, D.C. Allow for recreational use for adults 21 and over.
Two recent studies at Corvallis ‘ Oregon State University are investigating the changing patterns of college students living in legalized recreational use states.
One study finds that in these states, college students are steadily consuming more cannabis, while the other is investigating the effect of this increased consumption on that of other common recreational substances.
How legalization impacts the use of cannabis
Harold Bae, Ph.D., from the OSU College of Public Health and Human Sciences, and David Kerr, Ph.D., from the College of Liberal Arts, conducted the addiction research.
As part of the National College Health Assessment (NCHA) survey, it is the first study to investigate the impact of recreational legalization in multiple states, taking data from more than 850,000 students who self-reported their cannabis use twice a year.
The researchers analyzed survey data from students 18–26 years of age who had attended college in either of the seven states that had legalized recreational use by 2018 or the 41 states that had not.
The study received responses from students in 135 colleges in legalized states and 454 colleges in non-legalized states. Around 2008 and 2018, the students submitted responses.
Unsurprisingly, after legalization, the team found that cannabis use increased. In those states, students in states where the drug was still illegal were 18 per cent more likely to have used cannabis in the past 30 days than students.
Students in cannabis legalization states were also 17 per cent more likely to be frequent users, which the authors have described in the past 30 days as using 20 or more frequently. “It’s easy to look at the results,” says Kerr, “and think,’ Yes, rates would increase, of course.’ But we need to measure the impact these policy changes are having.”
Because they included ten-year data, the researchers were able to identify long-term trends.
The data revealed that students were 46 per cent more likely to have used cannabis after 6 years of legalization than students living in non-legalized states.
Just 32 percent of people in the U.S. think cannabis should be legal for medical use only, according to the Pew Research Center, and 8 percent believe it should be completely illegal. From 2012 to 2018 its use increased in states with recreational legalization from 21–34 percent and in other states from 14–17 percent.
The team behind the Addiction study, digging more deeply into their data, found that the increase in cannabis use was the most pronounced among students aged 21–26, females and students living off-campus.
The effect on other substances
Ph.D. nominee Zoe Alley, Bae, and Kerr analyzed the effects of increased cannabis usage on that of other recreational substances common among college students using the same data set as the first study.
Students also documented any use of nicotine, binge drinking, illicit drug use and misuse of prescription stimulants, sedatives and opioids for the NCHA study. The authors of the study found that increased use of cannabis only had a minor effect on other use, with two exceptions: alcohol and sedative misuse.
The team observed a greater reduction in binge drinking among students aged 21 years and older in states with legalized recreational use, compared to similarly aged students in other states. However, they saw an increase in sedative abuse among students younger than 21 in legalized states.
The findings taken together
The two studies are both aimed at providing a first look into the impact of legalizing cannabis on the behavior of college students. While further investigations will undoubtedly follow, this research offers an early glimpse of what to expect as more states pursue legalization, and perhaps the federal government does.
It contains at least one surprise: “We saw state-specific increases for[ cannabis] that went beyond national increases,” says Kerr, “whereas binge drinking was the opposite: a larger decrease in the context of national decreases.”