Alcohol causes more harm to society than any other drug in Canada, ranking far above tobacco, opioids, cocaine, methamphetamine and cannabis, according to a landmark scientific assessment published in the Journal of Psychopharmacology.
The study, led by researchers at the Centre for Addiction and Mental Health (CAMH), marks the first time multi-criteria decision analysis has been used to assess drug harms across Canada comprehensively. A national panel of 20 experts from six provinces evaluated 16 of the most commonly used psychoactive substances across 16 types of harm, considering both damage to users and wider societal impacts.
Alcohol received an overall harm score of 79 out of 100, significantly higher than tobacco (45), non-prescription opioids (33), cocaine (19), methamphetamine (19) and cannabis (15).
“When we look at harm to people who use drugs and harm to others together, alcohol clearly stands out,” said JF Crépault, senior policy advisor and lead author of the study. “Our findings highlight a major gap between the harms linked to alcohol and the way it is currently regulated in Canada.”
The findings align with previous studies conducted in the United Kingdom, the European Union, Australia and New Zealand, all of which identified alcohol as causing the greatest total harm.
Dr Jürgen Rehm, senior author and scientist at the Institute for Mental Health Policy Research, explained that the scores reflect population-level harm rather than individual risk. “Some substances, including opioids, cocaine, and methamphetamine, rank very high even though far fewer people use them, because the harms are so severe,” he said. “Alcohol combines serious harms with very widespread use, which is why it causes the greatest total harm in Canada.”
The two-day decision conference brought together experts from diverse fields, including addiction medicine, epidemiology, clinical psychology, public health, advocacy and harm reduction. They first scored each drug on a scale from 0 to 100 for each type of harm, then weighted the relative importance of each harm category before combining the scores.
The 16 types of harm evaluated included short- and long-term physical and mental health effects, social harms such as loss of relationships and employment, and wider impacts including economic costs, environmental damage and international consequences.
The researchers emphasised that drug-related harm extends beyond pharmacological effects to encompass how substances are regulated. “The key message here is that harm is not just about what a drug does to the body,” said Crépault. “How a drug is regulated shapes who uses it, how it is used, and how much harm it causes. Evidence-based policy can significantly reduce harm, and governments have a real opportunity to use regulation to protect public health.”
For alcohol specifically, the researchers pointed to proven measures such as controlling price, limiting availability, and restricting marketing and promotion as effective ways to reduce harm. They also called for policymakers to consider both the harms caused by substances themselves and those caused by the laws and regulations governing them.
The study noted that whilst some illegal drugs scored lower overall due to lower prevalence of use, prohibition itself creates additional harms. These include an unregulated supply in which content and potency are variable, as well as risky consumption patterns, such as using alone or sharing equipment.
The findings have particular relevance for the United Kingdom, where alcohol and tobacco also represent major public health challenges.
In England, there were 280,750 hospital admissions in 2023/24, where the main reason was primarily attributable to alcohol, with the most common causes being cancer (85,400 admissions), cardiovascular disease (41,430) and mental and behavioural disorders due to alcohol use (34,810). In 2023, there were 8,274 alcohol-specific deaths—the highest rate since 2006 and 4.6% higher than 2022.
The estimated cost of alcohol harm in England was £27.44 billion annually in 2024, including costs to the health service, crime and disorder, reduced workplace productivity, unemployment and social services.
Recent data from the Adult Psychiatric Morbidity Survey found that 18.0% of adults in England drank at hazardous levels or above in 2023/24, equivalent to approximately 8.4 million adults. Men were twice as likely as women to drink at hazardous levels (24.8% compared with 11.7%).
Tobacco remains responsible for the majority of drug-attributable deaths in England, and is identified as having the highest rates of dependence amongst users. The World Health Organization classifies alcohol as a Grade 1 carcinogen, the most carcinogenic type, and estimates it is wholly or partly responsible for over 200 different disease conditions globally.
The Canadian research team acknowledged several limitations, including that household surveys may significantly underestimate the prevalence of harmful and dependent drinking, and that the study focused solely on harms without accounting for any potential benefits substances might have at individual or societal levels.
Nevertheless, they concluded that the findings underscore “a failure to adopt policies to address alcohol-related harms, despite the known health harms and the existence of proven policy measures.”