Students who only smoke marijuana do better at school than classmates who smoke just tobacco, or who smoke both tobacco and pot, says a new study, which tracked substance use among teens over 30 years.
Researchers from the University of Toronto’s Dalla Lana School of Public Health analyzed data from a survey administered to nearly 39,000 Ontario students between 1981 and 2011. The Centre for Addiction and Mental Health asked students in Grades 7, 9 and 11 about their tobacco and marijuana use, and their academic performance.
The study found that marijuana-only users did better at school than their counterparts who smoked only cigarettes or who smoked both cigarettes and marijuana. However, the findings reflect the fact that fewer students smoke tobacco today compared to 30 years ago, and those that do make up a very “marginalized, vulnerable” population, says lead study author Michael Chaiton, assistant professor in epidemiology and public health policy.