National survey data found Canadian cannabis use rose from 14% before legalization (2018) to 20% by late 2020, with female use rising to match male rates for the first time and legal sources increasingly replacing the black market.
Policymakers studying legalization outcomes, public health officials monitoring cannabis trends, and anyone interested in how legalization affects population-level use.
14% to 20% use; female rates matched male
What the researchers found
Past-3-month cannabis use increased from 14.0% (2018) to 17.5% (2019) to 20.0% (2020). Daily or almost daily use rose to 7.9%. Female use rates rose to equal male rates for the first time. Use increased particularly among adults 25+ and in some provinces. Legal sourcing increased while reliance on friends, family, and illegal sources decreased.
Why it matters
This is the most comprehensive look at how Canadian cannabis use actually changed after legalization. The shift from illegal to legal sources suggests the policy is achieving one key goal, while the overall increase in use raises ongoing public health questions.
The numbers in context
Use: 14.0% (2018) to 17.5% (2019) to 20.0% (2020); daily use: 7.9%; female rates equaled male rates; legal sourcing increased; illegal sourcing decreased
How the study worked
Analysis of three quarters of the National Cannabis Survey: Q1 2018 (pre-legalization), Q1 2019 (post-legalization year 1), and Q4 2020 (two years post, also post-edible legalization). Nationally representative survey data.
What this study cannot tell us
Cannot disentangle legalization effects from COVID-19 effects on 2020 data. Self-reported use may be subject to social desirability bias. Response rates and representativeness may shift over time.
How to read the evidence
Nationally representative survey data over three time points spanning legalization, but self-reported measures and COVID-19 confounding in 2020 data.
When this study was published
Published in 2021 with data through 2020; Canadian cannabis market has continued to mature.
The bigger picture
The convergence of male and female use rates post-legalization is notable. It suggests that prohibition may have disproportionately deterred women from using cannabis, and that normalization has equalized access. Whether this equalization carries public health implications requires ongoing monitoring.
Questions still open
- How much of the use increase reflects new users versus previously illegal users now willing to report? Did COVID-19 independently increase cannabis use? Will use rates stabilize or continue climbing?
Common questions
Did legalization increase cannabis use in Canada?
Are Canadians buying legal cannabis?
Read the original research
Looking back from 2020, how cannabis use and related behaviours changed in Canada.
Health reports, 32(4), 3-14
Citation
Rotermann, Michelle. (2021). Looking back from 2020, how cannabis use and related behaviours changed in Canada.. Health reports, 32(4), 3-14. https://doi.org/10.25318/82-003-x202100400001-eng