Lessons from Cannabis Legalization in Canada: After 6 Years

After Cannabis Legalization: Early Observations and Lessons

Canada legalized nonmedical cannabis use six years ago, a process that has brought both promising developments and new concerns. In the first years after legalization, cannabis use became safer and some health harms were reduced. However, the spread of high-potency products and problems with how people consume them are drawing attention.

Cannabis Use: What Do the Numbers Tell Us?

According to 2024 data from Statistics Canada , among Canadians under 45, one third used cannabis in the past year. However, regular use is less common. Approximately 10% of people under 45 and 5% of those over 45 consume cannabis daily or almost daily.

Since legalization, 70% of cannabis users have reported buying from more than 3000 legal sources. As a result, cannabis-related crime has fallen substantially. Most of the 10000 drug offenses recorded in 2022 involved illegal importation or exportation.

Health Effects: Have Hospitalizations Decreased?

On October 5, 2023, JAMA Network Open published a study reporting that cannabis-related hospitalizations decreased after legalization. However, with the COVID-19 pandemic and expansion of the legal market, the rate increased again in some regions. This stands out as an area requiring attention.

The Effects of Cannabis Legalization in Canada

Product Safety and New Concerns

One of the greatest advantages of cannabis legalization has been greater confidence in product standards and improved safety. This has brought the potential for fewer adverse events. However, the growing availability of products high in tetrahydrocannabinol (THC), vaporizers and concentrate-infused pre-rolled joints raises concerns, particularly about overdose and long-term health effects.

According to Canadian public health expert Dr. David Hammond, many consumers struggle to control their dose of high-THC products, which can lead to unwanted health outcomes. Hammond also notes that the long-term health effects of these products remain uncertain.

• Related topic: What Are CBD, THC and Cannabis Oil? Health Effects of Substances Derived from the Cannabis Plant

Young People and Social Norms

Although social norms in Canada appear largely unchanged, easy access to cannabis and its normalization among young people have increased. Dr. Jennifer Donnan, an expert in this area, says young people are not adequately informed about cannabis, increasing the risk of uninformed consumption. In response, Donnan and her team developed an educational program based on harm-reduction strategies.

Research on Pregnancy and Fetal Development

Cannabis use during pregnancy is reported at a rate of 5% in some regions, rising to as much as 20% in marginalized groups. Research led by Dr. Sandeep Raha observed that compounds such as THC and cannabidiol (CBD) may cause biological changes in placental stem cells . This is thought to have potential effects on fetal development, hormone release and cardiac function. Raha notes that one difficulty in this research is the inability to control real-world doses and frequency of use.

Future Research Areas and Policies

Age Limits and Brain Development

Although the legal age for buying cannabis in Canada is 18, the effects of cannabis use at a young age remain debated, given that the brain continues to develop until age 25. High THC exposure may adversely affect the prefrontal cortex and hippocampus, causing difficulties with emotional regulation and cognition, and may increase the risk of psychiatric illnesses such as schizophrenia , according to Dr. Steven Laviolette.

Psychiatric and Neurological Risks

Laviolette's team is investigating how THC affects brain signaling pathways and neuroinflammation. They are also studying interventions, such as certain amino acid supplements, to reduce THC's adverse effects. Laviolette describes this period as "a real-world experiment involving millions of people" and stresses the need for more research to fully understand the effects of the more than 100 phytochemicals in cannabis.

A Message for Healthcare Professionals

Canadian scientists encourage healthcare professionals to take an open-minded approach to cannabis use. While acknowledging the limited evidence on its medical effects, Dr. Donnan emphasizes the importance of providing accurate, nonjudgmental information to patients. This approach may increase patients' trust in their healthcare providers and encourage healthier decisions.

Conclusion: Can Canada's Lessons Guide the World?

As a global pioneer in cannabis legalization, Canada is experiencing both benefits and challenges. More research is needed into areas such as the potential risks of high-THC products, a lack of awareness among young people and the effects of use during pregnancy. However, legalization has also produced positive outcomes, including a regulated market, reduced crime and improved product safety.

These experiences offer valuable lessons for countries seeking to shape cannabis policies worldwide. Open communication between healthcare professionals, scientists and policymakers is critical to understanding the health effects of cannabis and developing better regulations.