Article by Science Daily
In 2015, 38 percent of college students said they had used marijuana in the prior 12 months, up from 30 percent in 2006.
Daily or near-daily use of marijuana (having used 20 or more times in the prior 30 days) also has increased in recent years for college students, rising from 3.5 percent in 2007 to 5.9 percent in 2014 — the highest level of daily use measured in the last 34 years.
However, in 2015 their daily use fell back some to 4.6 percent, or one in every 22 college students. A decline in the degree of risk of harm associated with using marijuana may account for much of the increase in use. Since 2003, proportions of 19-to-22-year-olds seeing regular use of marijuana as dangerous to the user has fallen sharply — from 58 percent in 2003 to 33 percent by 2015.
“This increase in use and decrease in perceived risk of harm regarding marijuana use should be taken seriously by college administrators, parents and students themselves. We know through other research that frequent marijuana use can adversely affect academic performance and college completion,” said John Schulenberg, one of the study’s lead researchers and research professor at the University of Michigan’s Institute for Social Research.
In contrast to the story for marijuana use, other types of drug use are declining among college students. Nonmedical use of prescription narcotic drugs has been declining among college students since reaching a high in 2006 of 8.8 percent annual prevalence (that is, any use in the prior 12 months). By 2015, 3.3 percent of college students reported using any narcotic drug in the past 12 months without medical supervision — a drop of about six-tenths.
“It appears that college students, at least, are hearing and heeding the warnings about the very considerable dangers of using narcotic drugs,” said Lloyd Johnston, the study’s principal investigator and ISR distinguished senior research scientist and research professor.
Use of heroin, another narcotic drug, has been low among college students for many years. The highest annual prevalence recorded since 1980 was in 1998 at 0.6 percent, but the rate has been at or under 0.3 percent since 2005 and was down to 0.1 percent in 2015.
Use of amphetamines has started to decline among college students. From 2008 through 2012, the percentage of college students who reported using an amphetamine without medical supervision in the prior 12 months rose from 5.7 percent to 11.1 percent, likely due to more students using them to improve their academic performance. But, by the time of the latest survey in 2015, that had fallen slightly to 9.7 percent.