A gateway drug? Breaking down two commonly cited assertions by Tory senators as cannabis legalization nears

published on May 21, 2018 by Mike Hager in The Globe and Mail

As legislation to legalize recreational cannabis drags on in the Senate, two assertions about the drug are frequently cited by skeptics in the Red Chamber: that ending prohibition will lead to an increase in teen use; and that marijuana is a so-called gateway to harder drugs.

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M.J. Milloy, an infectious-disease epidemiologist at the BC Centre on Substance Use (BCCSU), said that while some people undoubtedly use cannabis then go on to other drugs like cocaine or heroin, vastly more people stick to cannabis and never progress to any other forms of drug use.

“[The gateway theory] has never stood up to scientific scrutiny, in part because it is more a popular concept and a cornerstone of prohibitionist policies rather than something that’s ever been observed among humans,” Dr. Milloy said.

Research is now emerging that shows cannabis may help people wean themselves off harder drugs such as crack, as a study co-authored by Dr. Milloy last year seemed to suggest.

Scientists at the BCCSU tracked 122 people who consumed crack in and around Vancouver’s Downtown Eastside over a three-year period and found that they reported using the drug less frequently when they opted to also consume cannabis.

“There is now emerging evidence to suggest that at least some people are using cannabis in an attempt to get off of certain drugs,” he said.