The data suggesting that youth cannabis use was on the rise even before legalization comes from a recent COMPASS study where more then 230,000 questionnaries were filled out by Canadian high school students in grades 9 to 12.
It found that almost ten per cent reported having used the drug at least once per week in 2017-18, with a further 18 per cent saying they had used it at least once in the last year.
Both weekly and occasional use reached their lowest points in 2014-15 and have since been rising steadily.
Alex Zuckermann, is a post-doctoral fellow with the Public Health Agency of Canada working in the School of Public Health and Health Systems at the University of Waterloo.
She said the surge in cannabis use among youth started well before legalization.
"What the data really shows, is that it is not enough to just look at the year before legalization. It's not like you get to legalization and that is when the switch is flicked and that's when the change happened. You've got all these changes happening before hand, and the conversation, and the changes in medical cannabis," she said.
Zuckermann noted that they saw a change in perception of marijuana starting around 2014 as medicinal use became more widespread and legalization was being discussed.
"I think it is definitely linked to medicinal use, because we see an increase in cannabis use after there was a change to how people could access medical cannabis, because you use to have to get a special excemption from Health Canada."
She believes these changing social norms may have contributed to the rise in youth cannabis use.
You can read more about the study here.
- KitchenerToday.com/Rogers Media