High school marijuana users have lower grades, says a University of Waterloo study. The research is the first of its kind since the Department of Public Safety noted it had no data on the impact of legal cannabis on school performance.
“Regardless of students’ aspirational goals for post-secondary education, any substance use is impacting high school performance,” said Dr. Karen Patte, lead author of the study Marijuana And Alcohol Use As Predictors Of Academic Achievement. “It’s important to try to prevent or delay cannabis use.”
The findings are based on surveys of 26,475 Canadian high schoolers in Grades 9 to 12 over three years. “The remaining question is how to prevent or delay usage,” said Patte. “It underlines the fact that, yes, we need to add work to prevention programs.”
Cabinet introduced legislation in Parliament to repeal a 1923 ban on recreational marijuana. Public Safety Canada in a 2016 report Cannabis Policy Performance Metrics acknowledged it had no research of the impact on students’ performance, insurance claims, productivity, policing costs or workplace drug bans.
“Students who began to use alcohol or marijuana were less likely to attend class regularly, complete their homework, achieve high marks and value good grades,” said the Waterloo research, published in the Journal Of School Health. Regular cannabis users were 50 percent less likely to aspire to post-secondary studies, compared to abstainers.
“It underscores the importance of further research to understand the risk on health and well-being,” said Patte. “Unlike alcohol or tobacco, there is much less research in this area.”
Bill C-45 An Act Respecting Cannabis would sanction the sale of up to 30 grams of dried cannabis to Canadians 18 years and older; allow users to possess up to 4 cannabis plants; and permit “informational” promotions by licensed processors and distributors.
Canadians are among the heaviest marijuana users in the world, according to Department of Health volunteer surveys. “Over 40 percent of Canadians have used cannabis as a drug in their lifetimes, and 12 percent have used it in the year preceding the survey,” Metrics said.
The Public Safety report noted police count some 73,000 marijuana offences a year under the current Criminal Code – about 80 percent for possession – and that marijuana accounts for 96 percent of illegal drug production known to police.