The national organization that represents physicians says Canadians shouldn't be legally allowed to smoke pot until they are 21 and should face restrictions on the quantity and potency of the drug until they are 25.

It's just one of a long list of recommendations the Canadian Medical Association made in its submission to the marijuana task force, which will advise the federal government on legalization. The CMA provided a copy of that submission to CBC News.

The question of age limits will be a significant one for Justin Trudeau's government as it develops its legalization plans. He and his party have repeatedly insisted legalization is the best way to keep pot out of the hands of young people, arguing the current system fails in that regard and funnels the profits to organized crime.

The CMA said in the submission that ideally the legal limit would be 25, because the brain is still developing until about that age. But the group said a lower legal age is needed to keep youth from turning to criminals to buy pot.

In the meantime, limits on how much pot a young person can buy and how strong it should be would discourage sharing with underage friends, said the CMA in its submission.

The legal drinking age is set by each province and territory, but the CMA suggested the legal age for pot consumption should be set nationally to reduce enforcement problems near territorial and/or provincial borders.

​The group, which represents some 83,000 physicians, also called for a public education campaign and harm reduction measures to counter myths like marijuana is not addictive or pot can actually make people better drivers.

While the legal drinking age is set by each province and territory, the CMA is suggesting the legal age for pot consumption should be set nationally. (Jonathan Hayward/Canadian Press)

Ban the strongest stuff, says CMA

Among the CMA's other recommendations to the federal government:

Limit how much pot one person can buy, in order to reduce trafficking.

Take adequate time to prepare for legalization and consider a phase-in period or pilot projects.

Start collecting national data on marijuana-related emergency room visits, rates of drug-impaired driving, unintentional poisonings and other public health problems.

Prohibit marketing and advertising of pot, similar to the restrictions on cigarettes.

Ban "high potency" marijuana products and restrict certain types of products. The CMA expressed particular concern about children overdosing on edibles, such as marijuana cookies.

Make more mental health and substance abuse services available.

Don't allow home cultivation of pot other than for medical purposes.

Don't permit public smoking of pot due to the risk of secondhand smoke.

The group's written submission also discourages cheap pot, saying that pricing and taxation should be used to discourage use — though it also notes the price shouldn't be so steep it encourages illegal production.

The CMA points to one report suggesting legalization could create a $10 billion a year industry in Canada. It argues the government's portion of those revenues should be invested in covering the health and social costs of legalization. That, according to the CMA, means distributing most of that money to the provinces and territories, since they pay for health care, education and other social services.

The CMA asked a selection of its members what kind of distribution system they thought was best. The number 1 choice was existing non-health-care structures such as liquor stores, with legal store fronts, like so-called marijuana dispensaries, coming in a close second. Almost 60 per cent strongly disagreed with selling marijuana through pharmacies.

Harms versus benefits

The CMA said it wouldn't weigh in on whether pot should be legalized. Instead its report said that since the government is pursuing legalization, it was offering advice to help protect individuals and public health.

Still, the CMA did note that the current situation had resulted in "considerable harm to society," pointing to many people who have criminal records for non-violent drug offences and the benefits for organized crime.

"Legalization and strict regulation of marijuana for recreational use seeks to reduce health and social harms, particularly in higher risk groups; however, with the increased access, there could be an inverse effect, with the potential that harms could be intensified. There is also the considerable risk that the degree of 'normalization' of use that already exists could increase."

In the group's submission it noted health concerns including addiction, cardiovascular and pulmonary effects and mental illness.

It pointed to statistics from Colorado, which legalized marijuana in 2014, that show an increase in the number of marijuana-related traffic deaths, more cases of intoxication and other problems, as well as overdoses in children who consumed edible marijuana.