Results of a recent study showed that the optimal age to begin using cannabis is around 19 years old.  This is according to research published in May in the medical journal BMC Public Health. The paper is titled, “Too young for cannabis? Choice of minimum legal age for legalized non-medical cannabis in Canada.  The study was conducted at the Memorial University School of Pharmacy.   The debate over what age to restrict legal cannabis use has been ongoing for years.  Many scientists believe that brain development continues until the age of 21, while others are now arguing that risks can be minimized after the age of 19.  Associate Professor Dr. Hai Van Nguyen headed the study; Dr. Nguyen is the current Canada Research Chair in Health Policy Evaluation and Health Care Sustainability.  According to the study, researchers concluded that the ideal minimum legal age (MLA) for cannabis use is approximately 19 years.  Dr. Nguyen told Science Daily, “Prior to legalization, the medical community recommended a minimum legal age of 21 or 25 for non-medical cannabis use in Canada. This recommendation was based on scientific evidence around the potential adverse impacts of cannabis on cognitive development. However, policymakers feared a high minimum legal age may lead to large underground markets, with those under the legal age continuing to use cannabis illegally. Ultimately, a lower legal age of 18 or 19 was decided across provinces, however there remains ongoing debate and calls to raise the legal age to 21.” The conclusion was based on a regression analysis of a range of different outcomes in those who began using cannabis before and after the age of 19.  Outcomes that were measured included “educational attainment, current cigarette use, and self-reported general and mental health.”  “Taking into account all measured outcomes, our results indicate that, contrary to the Canadian federal government’s recommendation of 18 and the medical community’s support for 21 or 25, 19 is the optimal minimum legal age for non-medical use," said Dr. Nguyen. “Keeping the legal age below 21 may strike a balance between potential increases in underground markets and illegal use, and avoiding the adverse outcomes associated with starting to use cannabis at an earlier age.” The researchers “found different MLAs for different outcomes: 21 for educational attainment, 19 for cigarette smoking and mental health and 18 for general health. Assuming equal weight for these individual outcomes, the ‘overall’ MLA for cannabis use was estimated to be 19 years.” In the United States, consumers must be 21 years old before consuming cannabis in recreational states.  In Canada, the MLA for cannabis use is 19 across the country, however, in Alberta, lawmakers passed legislation lowering the MLA to 18. This is the first cannabis-related study to come out of Dr. Nguyen’s lab, however, Dr. Nguyen has been involved in multiple other studies that are worth noting, including a recent 2020 publication titled, “Intended and unintended effects of banning menthol cigarettes,” and another 2019 paper titled, “Environmental tobacco smoke exposure among electronic cigarette users.” You can find out more information and read the study for yourself here.