Who are the main users of cannabis in Canada? 

UBC Northern Medical Program Professor Dr. Russ Callaghan has found that a small proportion of cannabis users, the upper 10 per cent of heaviest-using individuals, consumed approximately two-thirds of all cannabis used in Canada in 2018.

Dr. Callaghan and his team looked at data from the 2018 National Cannabis Survey, which assessed patterns of cannabis use among Canadians at least 15 years old. They found that males reported consuming more cannabis by volume than females (approximately 60 per cent versus 40 per cent), with young males (15-34 years old) being disproportionately represented in the heaviest-using subgroups.

“This is the first study to identify this pattern, and it may be important for public-health strategies in designing interventions to reduce cannabis-related harms,” said Dr. Callaghan, the study’s lead author. “The findings are similar to those in the alcohol field, where we have found that a small subgroup of drinkers usually consumes the majority of alcohol in the population.”

“There is some evidence that most alcohol-related harms in society are not found among the heaviest-drinking individuals, but rather in the much more numerous low-to-moderate-drinking groups. At this time, we don’t know if the same pattern exists in relation to cannabis as it does for alcohol.”

Understanding cannabis use patterns in Canada could be used for targeted interventions for the heaviest-using groups, or broad-based population-wide policies if the majority of the burden of cannabis-related harms are found to be in low-to-moderate-using individuals.

“Future studies related to this project will further investigate the characteristics of the heaviest-using cannabis user group, as well as assessing how cannabis-related harms are distributed in Canadian society across individuals using different quantities of cannabis.”

The project included a team of researchers from UNBC, the University of British Columbia, the Centre for Addiction and Mental Health (CAMH), and the Canadian Institute for Substance Use Research at the University of Victoria.