According to research conducted at Oregon State University and recently published in the journal Psychology of Addictive Behaviors, recreational marijuana use increased among the state’s undergraduates after adult use became legal. The study, led by David Kerr, used information taken from voluntary health surveys across the country over several years.

Students were asked about their use of marijuana, tobacco, alcohol, and other drugs in the past thirty days. The study found that after recreational marijuana became legal in Oregon, students showed “increases in rates of marijuana use” and “decreases in tobacco use” relative to students in which recreational marijuana is not legal. The study also found no significant difference in use rates between students who were under the legal age of twenty-one and those who were not.

Increase in underage use

“And even though recreational use is only legal at age 21,” Kerr notes, “younger students also reported an uptick in marijuana usage. That may be an unintended side effect of legalization.” In Oregon, the drinking age is twenty-one.

According to the surveys, in recent years students across the country reported marijuana use in the previous 30 days in the range of about 19 to 23 percent. Use has been increasing across the nation, regardless of legality. After legalization in Oregon, students there reporting use in the previous thirty days increased from about 25 to 30 percent.

“Some would say that’s a concern because marijuana use, particularly in young people, is linked to negative health and achievement outcomes,” Kerr said. “On the other hand, alcohol and tobacco take a huge toll on public health and it is possible that marijuana legalization will affect how many people use other substances.” Kerr also acknowledged that because of the stigma of illegal behaviors, self-reporting may have increased after legalization (even though the surveys are anonymous), with a possible result of a showing of an increase in use when the reality was only an increase in reporting. “It’s possible these changes we saw reflect the changes in norms and beliefs that led to legalization, rather than the law change itself,” Kerr said.

Tobacco and alcohol use are down

Kerr’s survey results show that tobacco use has been in steady decline. An almost equal percentage of students reported use in states where marijuana is legal and where it is not, but the number has dropped more in legal states. Reported tobacco use generally is about 9 to 15 percent. Alcohol use among students has gone down in Oregon since legalization, but it is still higher than in states without legal marijuana. The lowest reported rate of alcohol use in the last thirty days was 60 percent (among students nationwide) and the highest almost 75 percent (in Oregon). Alcohol use rates generally tended toward rates of 65 to 70 percent.

The survey also indicates that at colleges, binge drinking, described in the survey as having “been drunk” or having four to five drinks, is significantly more common than marijuana use. Nationwide binge drinking rates in the previous month ranged from 32 to 44 percent, while marijuana use rates ranged from 19 to 23 percent.

According to a December 2016 Marijuana report published by the Oregon Health Authority, “Adults in Oregon are more likely than adults in the United States to use marijuana.”

Another, January 2016, report states: Approximately half (48%) of Oregon adults report they have ever used marijuana. One in 10 (11%) Oregon adults report they currently use marijuana; use is higher among men (14%) than women (8%). Young adults are the highest reported use age group (18% among ages 18–24 years). Oregon’s adult marijuana use is higher than the nation’s adult use.

According to Kerr’s study, the number of Oregon’s college students who reported using marijuana in the last month increased after legalization. While the Health Authority reports do not address increases after legalization, they do show that all adult use in Oregon, like that of college student use, is above the national average.

What do you think? Is increased marijuana use among college students a health issue? Leave a comment below.

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