Choice of minimum legal age (MLA) for cannabis use is a critical and contentious issue when it comes to legalizing recreational cannabis. In this blog, the authors of a study published today in BMC Public Health discuss their research which compares later life outcomes among people who started using the drug at different ages and finds that there is merit in setting 19 years as the MLA for recreational cannabis use.
An increasing number of jurisdictions including Mexico, New Zealand, Russia, Luxembourg and several US states are looking to legalize non-medical cannabis. The decision to legalize cannabis however comes with a contentious question for policymakers: What should be the minimum legal age (MLA) for cannabis consumption? While a low MLA can discourage the underground cannabis market, cannabis consumption before age 25 is said to negatively impact brain development. Policymakers, thus, face a difficult tradeoff between curtailing illegal economic activity and safeguarding adolescents’ well-being.
Our study published in BMC Public Health shows that there is merit in choosing 19 as the MLA for non-medical cannabis use. We reached this conclusion by looking at how Canadians, who started using cannabis at different young ages, differ in several important outcomes (educational attainment, cigarette smoking, self-reported general and mental health) later in life.
Why did we do this study?
Canada was the second country in the world to legalize non-medical cannabis in October 2018. Ahead of the legalizatio n, the federal government recommended a MLA of 18 years. However, after public consultations and for harmonization with the existing minimum legal ages for alcohol and tobacco use, most Canadian provinces set 19 as the minimum legal age; the two exceptions were Quebec and Alberta which opted for 18. Two years into legalization, the policy on MLA for cannabis use in Canada is still evolving. In particular, Quebec revised its MLA to 21 in October 2019 and there have also been calls to raise minimum legal age to 21 in Ontario. Notably, evidence that could shed light on the merits of different proposed MLAs was lacking.
Individuals starting cannabis at age 19 have later life outcomes that are better than those starting it ate age 18
We found that most later life outcomes are better for individuals starting cannabis at age 19 than those starting it at age 18 but not worse than those starting cannabis between age 20 and 25. These results imply that age 19 is the optimal MLA for cannabis use.
This finding of MLA of 19 is different from the Canadian federal government’s recommendation of 18 and stands in contrast with medical community’s support for age 21 or 25. Yet, it appears to be plausible: age 19 is high enough to address concerns over potential adverse outcomes associated with using cannabis at young age while low enough to discourage the illegal market for the underage.
Our findings will be useful for policymakers in jurisdictions planning to legalize non-medical cannabis. Meanwhile, in Canada, as the post-cannabis legalization era evolves, it will be important to watch trends in youth’s and young adults’ use and monitor harms over time while ensuring that the legal market is tightly regulated and that cannabis companies do not stray from restrictions on marketing, sales, and packaging that might make products more appealing and accessible to children.
MiShirtGuy on May 14th, 2020 at 13:12 UTC »
This is something I think about as a new father and as a newer cannabis user and grower. In Michigan, legal cannabis is the new reality that we all fought so hard to achieve. I‘ll be 40 later this year, and I really didn’t start smoking cannabis until I was 36. It just didn’t interest me earlier and I was good with alcohol. It’s weird that I can just pick it up and enjoy it, and not “feel” any need for it beyond enjoying it at the end of my day with a drink. I don’t feel any withdrawals or dependence on it, and will go days without smoking just because it’s not something I actually “need” to do. Compare that to my wife who has been smoking cannabis since her teens. The picture of my wife compared to myself in regard to focus, memory issues, and spacial awareness is staggering. While I’m super happy that the freedom is there to grow and partake, I absolutely wouldn’t be for my 18 month old son to start experimenting until he was an adult, and I’d really like to see him wait on any kind of serious usage until after he’s 21. The effects on brain development are obvious for anyone who is observant. On the same token, I’ll go longer without my anti-anxiety pills (I’ve taken L-Theanine for anxiety for last decade, absolutely life changing for anyone interested) because of the relaxing and anxiety reducing effects of smoking an Indica. But as an adult with my more formative brain development behind me, the benefits totally outweigh the risks in my mind and my experience. Raising a child in this new reality will be interesting, as I have no plans to sugar coat or lie to my son what recreational drug use is and isn’t, and what harms and benefits it entails. I hope that being honest with him will help him have the maturity to do as Mom and Dad says, not as we do, but that’s up to the future I suppose.
JDCarrier on May 14th, 2020 at 13:10 UTC »
The authors’ conclusion is very simplistic. Epidemiological data on the outcomes of starting cannabis at age 19 vs 18 vs 25 is a different issue altogether than the effects of public policies on individuals’ behavior. This is the same reason why there is disagreement in some jurisdictions between psychiatrists and public health experts on setting different legal ages for different substances. This study’s result don’t solve this issue at all and shouldn’t get policymakers’ attention without input from experts on the effects of public policies.
ColeusRattus on May 14th, 2020 at 11:56 UTC »
Studies like these generally have a hard time differentiating between causation and correlation.
Might be that people who feel the need to do drugs earlier are generally more susceptible to mental health issues.
Not that I endorse early drug use. Just a point I want to make.