In North America's burgeoning experiment with legal weed, reefer madness myths are falling like dominos. Emerging from the shadows of prohibition's rumor-filled past, researchers across the United States and Canada are using newly available post-legalization statistics to sort out the social effects of cannabis use and its reform, as well as release long-term comparisons that disprove a number of anti-marijuana advocates' primary arguments. Adding to the refreshed canon of cannabis education, two studies published this month dispute persistent rumors of legalization's ramifications on teenage usage and ganja's stigma as a gateway drug.
The first study, published February 12th in the journal Drug and Alcohol Review by researchers from Vancouver, Canada, took a longitudinal look at the myth that cannabis is a "gateway drug" that leads users to trying harder substances. Following "street-involved youth" for 10 years, the study's authors compared rates of injection drug use with weed, and found a significantly lower rate of intravenous drug use among regular cannabis users.
"[We] observed a high rate of injection initiation among at-risk street-involved youth," the study's authors wrote. "Our results indicate that periods of frequent cannabis use were associated with slower rates of initiation: daily cannabis use was associated with a 34 percent decrease in the hazard rate of injection initiation."
As opioid abuse continues to wreak havoc across the U.S. and, to a lesser extent, Canada, American politicians and law enforcement officials have repeatedly brought up the gateway theory as a reason to block cannabis legalization efforts, despite a lack of evidence supporting the "slippery slope" claims. A number of studies, including the new Vancouver research, suggest the direct opposite: marijuana prevalence actually decreases opioid use.
In another study looking at cannabis use over decades, but focusing specifically on the consumption habits of American teenagers before and after legalization, researchers from Columbia University's Mailman School of Public Health found no significant changes in youth marijuana habits. In other words, the research debunks any fear that legal weed could quickly corrupt the country's impressionable teens.
"For now, there appears to be no basis for the argument that legalizing medical marijuana has increased teens' use of the drug," Deborah Hasin, PhD, professor of Epidemiology at Columbia's Mailman School, and senior author of the study, said in a press release. "However, we may find that the situation changes as commercialized markets for medical marijuana develop and expand, and as states legalize recreational marijuana use."
Even with the minor concession about possible future changes, the Columbia University study, published this week in the journal Addiction, is one in a long series of studies suggesting that American teens have largely been unaffected by cannabis legalization reform.
Of course, marijuana's federally illicit status has prevented most forms of in-depth research into the plant itself, but as social sciences begin to sharpen their focus on cannabis and the changing dynamics of legalization, it certainly appears that prohibitionist arguments will continue to collapse, falling by the wayside in favor of facts and evidence.
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