In Canada, adults can legally consume cannabis as young as age eighteen, the federal minimum. In the United States, every state with legal adult use cannabis has opted to align cannabis with alcohol, and set the age limit at 21. But, new research suggests the best age might be 19.
Canada became the second country to legalize cannabis for adult use, in 2018, and it’s unlikely it will be the last. And just as legalization debates take place in the Caribbean, Europe, and Latin America, new research published Thursday in the peer-reviewed journal BMC Public Health sheds light on the age-old age question: When it comes to cannabis policy, who’s an adult?
The population-based cross-sectional study sought “to assess the merits of the age thresholds of 18, 19, 21 and 25 years being debated in policy discussions,” as the age limit, considering there will be some underage cannabis use regardless of where it is set, “represents a trade-off that policymakers face between curtailing illegal economic activity versus safeguarding adolescents’ well-being.”
Researchers analyzed data from two government surveys, the Canadian Tobacco Use Monitoring Survey, between the years 2004 and 2012, and the biennial Canadian Tobacco, Alcohol and Drugs Survey, which was conducted in 2013 and 2015. After assessing outcomes—like mental health, general health, and cigarette smoking—of cannabis consumers who started at different ages, researchers concluded that age nineteen is the “optimal” minimum legal age “for non-medical cannabis use.”
The data yielded some surprises, the study’s author, Hai V. Nguyen, an associate professor at Memorial University of Newfoundland’s School of Pharmacy, told Cannabis Wire.
“Several later life outcomes,” Nguyen said, “from starting cannabis use at age nineteen are not different than starting at or after age twenty-one. Educational attainment is an exception, where we found that those who started using cannabis at nineteen have worse education attainment than those who started at twenty-one or later.”
The researchers plan to update their study as more data after legalization become available.
When asked what prompted the research, Nguyen said that the group of researchers initiated the study themselves after recognizing the policy debates around cannabis use and age. “There has been a huge debate on the appropriate minimum legal age for cannabis in Canada, both prior to legalization and thereafter.” Recently, Nguyen told Cannabis Wire, Quebec changed its minimum legal age for non-medical cannabis from eighteen to twenty-one. There have also been calls to raise the minimum legal age to twenty-one in Ontario, he said. This prompted the researchers to look at the optimal minimum legal age “based on the age of first cannabis use and later life outcomes.”
While Canada’s government set the minimum legal age for cannabis consumption at eighteen, provinces are allowed to set their own policies. But, Canadians aren’t settled on the minimum legal age for cannabis use, either. A survey from the Angus Reid Institute, published in 2018, found that Canadians were largely split, with 27% agreeing that eighteen years old was the right age, and 26% reporting that they thought twenty-one years was “more appropriate.” Still, 23% said they wanted the legal age “even higher.”
Legalization debates were actively underway in a number of states and countries before the COVID-19 pandemic hit, and they’re likely to pick back up as the virus numbers plateau and drop.
“Our findings will certainly be useful for policymakers planning to legalize non-medical cannabis in their jurisdictions. Several jurisdictions including Mexico, New Zealand, Russia, Luxembourg, and several US states are planning to legalize non-medical cannabis. Our study can provide useful insights to inform the decision on the optimal [minimum legal age] in these jurisdictions,” Nguyen said.
There were several limitations, one being that the data used was from before Canada’s adult use legalization. In addition, there was a lag in time between when people responded to the survey and when they actually first used cannabis; this was especially true for older adults, meaning some respondents “may not accurately recall their age of first cannabis use.”
“Nevertheless, our estimates provide a useful indication for potential impacts of the cannabis legalization,” researchers concluded.
