"What’s the best minimum legal age for cannabis?"

The question in the title of this post is the headline of this effective new Leafly article, which builds off the research noted in this prior post about the "right" minimum age for legal access to recreational cannabis.  Here are excerpts:

When it comes to legal cannabis, the random collection of ages across North America is curious. Every US state that allows recreational cannabis sales requires customers to be at least 21 years old. In Canada the minimum age is 19, except in Alberta (where it’s 18) and Québec (which started at 18 but raised it to 21 earlier this year).

In most jurisdictions, medical marijuana is legal for people age 18 and older, with a doctor’s recommendation.

What difference does it really make if someone is 18, 19 or 21? A research team at Memorial University in Newfoundland, Canada, recently investigated the question. Instead of looking at the immediate health and safety of young adults, they assessed later life outcomes — namely educational attainment, lifetime cigarette smoking habits, and general physical and mental health. In their study, the Memorial University team concluded that the ideal minimum legal age for cannabis was 19....

Health experts cite THC exposure in adolescents causes changes to the brain’s folding patterns, decreased neural connectivity, thinning of the cortex and lower white matter, among other symptoms. However, one recent study suggests any changes to brain structure caused by cannabis use in adolescence cleared up by the time subjects were in their 30s.

Another ongoing study in the Saguenay region of Quebec took MRI scans of over 1,000 adolescent brains in 2002, and the same subjects are currently being re-evaluated as adults — results pending.

If the serious nature of brain health is such a risk, why not just make cannabis illegal until a person’s mid-20s? In the real world, policymakers have to weigh human nature’s penchant for the forbidden with appropriate rules and consequences. In an ideal world, sure — and in this ideal world underage kids never go looking for cannabis from illicit sources, either. In the real world, though, policymakers have to weigh human nature’s penchant for the forbidden with appropriate rules and consequences. In an ideal world, alcohol would also be outlawed for health reasons, but we all know how Prohibition worked out.

Prior to the Oct. 2018 opening of legal cannabis sales in Canada, a government task force took a hard look at the best-legal-age question. That group found that the higher the minimum legal age, the more likely adolescents will seek out unregulated sources, risking both consumption of potentially more dangerous products and also incarceration.

Prior related post:

• "Too young for Cannabis? Choice of minimum legal age for legalized non-medical Cannabis in Canada"