A government-funded study published in the Journal of Psychopharmacology has produced the most comprehensive assessment of drug-related harm ever conducted in Canada, and the results reinforce what researchers have been saying for more than a decade: alcohol and tobacco cause significantly more harm to individuals and society than cannabis.
The study, titled "Drug harms in Canada: A multi-criteria decision analysis," was supported by the Canadian Institutes for Health Research. A panel of 20 experts from six provinces evaluated 16 substances across 16 dimensions of harm, covering everything from drug-related mortality and physical health damage to economic costs, harm to families, and organized criminal activity. Each drug was scored on a scale of 0 to 100.
The Harm Scores
The results are striking. Alcohol scored 79 out of 100, making it the most harmful substance overall by a wide margin. Tobacco followed at 45. Non-prescription opioids, including fentanyl, scored 33. Cocaine and methamphetamine each scored 19. Cannabis scored 15, the lowest of all major substances evaluated in the study.
Tobacco ranked first in four of the 16 individual harm categories: drug-related mortality, drug-specific damage to physical health, dependence, and environmental damage. Alcohol dominated the categories measuring harm to others, including harm to families, economic costs, and community damage.
Cannabis's Biggest Harm: Organized Crime
Perhaps the most revealing finding in the study concerns cannabis specifically. Cannabis's highest individual harm score was not for any health effect. It was for organized criminal activity. The researchers noted that while more than 70 percent of Canadian cannabis consumers now purchase from legal sources, criminal organizations remain heavily involved in the remaining illegal market, from production to distribution.
In other words, the biggest measurable harm associated with cannabis is not caused by the substance itself, but by the prohibition that drives its supply into the hands of criminal networks. This finding carries enormous implications for the policy debate in Europe, where the Netherlands, Germany, Czechia, and others are actively working to replace illegal supply chains with regulated alternatives.
Consistent With Global Research
The Canadian findings are not an outlier. They align closely with every comparable international study conducted over the past 15 years. The landmark 2010 analysis by British neuropsychopharmacologist David Nutt, published in The Lancet, was the first to rank alcohol as the most harmful drug overall when both individual and societal harms were considered. Studies conducted in Australia, the European Union, New Zealand, and the United Kingdom have all reached the same conclusion.
A 2024 study published in the Journal of Studies on Alcohol and Drugs found that secondhand harms from alcohol use were substantially more prevalent than harms from any other drug. Another recent evaluation in the United States ranked only fentanyl, methamphetamine, crack, and heroin above alcohol in terms of potential harm. Cannabis consistently appears near the bottom of every harm ranking.
The Policy Disconnect
The study's authors concluded that the high harm score for alcohol "underscores a failure to adopt policies to address alcohol-related harms, despite the known health harms and the existence of proven policy measures." They urged governments to consider the harm caused not only by drugs themselves, but also by the laws and regulations that govern them.
This is the central tension in drug policy worldwide. Alcohol, with a harm score of 79, is legal, heavily marketed, and available in virtually every shop and restaurant. Tobacco, scoring 45, is legal and sold at every gas station and supermarket. Cannabis, scoring 15, remains criminalized in most countries, with possession carrying fines or prison sentences in many jurisdictions.
For European policymakers weighing the next steps on cannabis reform, the evidence continues to accumulate in one direction. The Dutch wietexperiment is testing whether regulated supply chains can reduce the organized crime that this study identifies as cannabis's greatest harm. Germany has legalized home cultivation and cannabis clubs. Czechia has legalized personal possession and cultivation as of January 2026. Basel, Switzerland, has been running a regulated pharmacy sales trial for over three years with positive results.
The question is no longer whether cannabis is less harmful than alcohol and tobacco. The science settled that years ago. The question is how long policymakers will continue to treat it as though it were more dangerous.
