Did Cannabis Usage Rates Spike In Uruguay And Canada Post-Legalization?

A common prediction made by cannabis opponents when cannabis policy modernization proposals are being considered is that cannabis consumption rates, particularly cannabis misuse rates, will dramatically increase. Cannabis opponents have made that claim for decades, often going unchallenged.

This scenario is no longer hypothetical, with multiple countries having adopted adult-use cannabis legalization measures. Consumption data generated from those jurisdictions can be examined and analyzed, providing insight into what actually happens when countries adopt modernized recreational cannabis policies.

Uruguay was the first country to ever adopt a national adult-use legalization measure involving cannabis that contains high THC levels. Low-THC production and use (industrial hemp) were permitted in various jurisdictions before Uruguay legalized recreational cannabis in 2013. However, Uruguay was the first nation to legalize high-THC production, possession, and use by adults for recreational purposes.

Over a decade after Uruguay implemented legalization, below is what we know about consumption rates in the South American country via an insightful article by reporter Javier Hasse for Forbes. The data is derived from a presentation by Mercedes Ponce de León, director of Expo Cannabis Uruguay, at the C-Days 2025 conference in Barcelona.:

• ‘Problematic use’ has remained steady at 2.1% since 2011
• Overall consumption rates fell from 14.6% in 2018 to 12.3% in 2024
• The average age of initial cannabis use rose from 18 to 20 years

Uruguay’s legalization model involves permitting adults to legally access regulated recreational cannabis through one of three channels. The first is through the nation’s pharmacies, 40 of which sell adult-use cannabis products containing very specific ratios of THC and CBD. A reported 75,498 consumers are registered to make recreational cannabis purchases from Uruguay’s pharmacies.

The second is through the nation’s licensed member-based cultivation associations, of which there are currently 460 that are active. A reported 15,162 consumers are members of a licensed cultivation association. Lastly, adult consumers can cultivate their own cannabis in their private residences, up to six plants. A reported 11,465 consumers have registered to cultivate cannabis at home.

Canada’s legalization model permits a more robust commerce system, including permitting recreational cannabis sales to non-residents. Uruguay limits recreational cannabis sales to residents of the South American nation only. Canada first implemented its legalization model in 2018.

A team of academic and health researchers based in Canada recently examined reported cannabis consumption data, intending to determine whether cannabis use or misuse changed “among adults in the 5 years following recreational cannabis legalization in Canada.” The researchers’ findings were published in the academic journal Substance Use and Addiction.

“This prospective cohort study included data from community-dwelling adults who participated in up to 11 biannual assessments from September 2018 to October 2023 in Ontario, Canada. Data were analyzed from November 2023 to January 2024.” the researchers stated about their methodology.

“In this prospective cohort study of community-dwelling adults in Canada, cannabis use frequency increased modestly in the 5 years following legalization, while cannabis misuse decreased modestly.” the researchers concluded. “These changes were substantially moderated by prelegalization cannabis use, with more frequent consumers of cannabis before legalization exhibiting the largest decreases in both outcomes.”

Data from both Uruguay and Canada demonstrate that national adult-use cannabis legalization does not automatically result in a massive spike in consumption rates, problematic or otherwise, debunking claims made by cannabis opponents. The same is true for localized adult-use cannabis commerce reform, as demonstrated by the results of research conducted in Switzerland, where regional adult-use cannabis commerce pilot trials are operating.

An interdisciplinary research team affiliated with the Addiction Department of the Department of Health of the Canton of Basel-Stadt, the University of Basel, the University Psychiatric Clinics Basel (UPK), and Psychiatric Services Aargau recently published results from a study that relied on data from the Weed Care pilot trial project in Switzerland.

The study’s findings, which are the first academic reporting of its kind, were published on the University of Basel’s website in addition to being published in the academic journal Addiction.

“We measured the effects of public health-oriented cannabis access compared with the illegal market on cannabis use and related mental health outcomes in adult cannabis users.” the researchers stated about their study. “This was a two-arm, parallel group, open-label, randomized controlled trial. Follow-up outcome measurement took place after 6 months.”

“The primary outcome was self-reported severity of cannabis misuse after 6 months, as measured by the Cannabis Use Disorders Identification Test – Revised (range 0–32). Secondary outcomes involved depressive, anxiety, and psychotic symptoms, cannabis consumption amount, alcohol, and drug use.” the researchers wrote regarding their investigation’s measurements.

“Public health-oriented recreational cannabis access may decrease cannabis use and cannabis-related harms, especially among those using other drugs.” the researchers concluded.

“Furthermore, the study was able to dispel fears that legalization could exacerbate the psychopathological symptoms associated with cannabis consumption in addition to consumption itself: after the first six months, there was no difference between the two study groups in terms of depression, anxiety or other symptoms.” stated the University of Basel on its website.

“The interim assessment after two years of study shows a significant improvement in the mental state of the approximately 300 or so participants who are still taking part.” the University also wrote.

Earlier this year, Marijuana Moment reported that a government-commissioned report found that  Switzerland’s adult-use cannabis legalization pilot program is “running smoothly,” with “no indication of any disturbances to public order.”

“About two years after the pilot program launched in seven municipalities across the country, the Federal Office of Public Health (FOPH) study—carried out by the University of Lausanne and the University of Applied Sciences Northwestern Switzerland—generally determined that the initiative has been a success.” the outlet also reported.

Previously published government data from the United States found that in jurisdictions where adult-use cannabis legalization was adopted, consumption rates among minors had reduced post-legalization compared to pre-legalization.