Dr. Benedikt Fischer of the Simon Fraser University in Vancouver and a scientist at the Centre for Addiction & Mental Health said more than one in 10 Canadian adults -- and about one in three young people ages 16-25, report using marijuana during the past year.
Despite the prevalence and health risks associated with marijuana use, Fischer pointed out Canada has not taken a public health approach to address its ill effects, as it has done with alcohol, tobacco and injection drug use.
"Misinformation about cannabis can be dangerous," Fischer said in a statement.
For example, surveys indicate many young marijuana users say it is safe to drive after using marijuana, but Canadian research shows a significant number of traffic fatalities in young adults are attributable to marijuana use.
"A broad-based public health approach to cannabis use would include a prevention strategy for young people, risk reduction strategies for at-risk users and better access to treatment for problem users," Fischer said.
Among the guidelines suggested are:
-- Avoid pot-smoking by the young, which is associated with a number of problems, including mental illness and dependence and a greater likelihood of advancing to other illegal drugs.
-- Avoid frequent use of marijuana, usually defined as daily or near-daily use, which has been linked to such health problems as lower cognitive and memory performance, and risk of dependence.
-- Avoid driving for 3-4 hours after using marijuana.
-- Pregnant women should abstain from marijuana use.
The findings were published in the Canadian Journal of Public Health.