Marijuana Isn’t Gateway Drug To Heroin, Cocaine, Other Substances, Study Finds

Photo Credit: Brandon Marshall

A new analysis finds that while marijuana legalization has led to higher rates of cannabis consumption in Colorado and other states with similar laws, there’s no evidence that it’s fueling abuse of more addictive drugs, including heroin and cocaine.

That’s the conclusion of a just-issued report from LiveStories, which specializes in the analysis of civic data. LiveStories founder Adnan Mahmud summarizes the results like so: “We haven’t found any strong correlation that suggests increased marijuana use leads to increases in other substance abuse.”

Mahmud stresses, “We weren’t looking for causation,” as a scientific study might. “We were looking for a correlation. And we didn’t find that was the case.”

LiveStories is “the Bloomberg for civic data,” Mahmud maintains. “We collect data about how people live: everything from the unemployment rate to income to rents to cancer rates to graduation rates — all the data we can find about quality of life. Then we bring it together and analyze it in connection to different topics. Last year, we did a massive analysis of the gender-pay gap around the country in different cities and looked at the opioid epidemic. And for this report, we decided to take a deep dive into marijuana legalization.”

Specifically, the analysis looked at data from Colorado, Washington, Oregon and Alaska, all of which have legalized limited recreational marijuana sales, and then compared it to national averages. Data for the states was drawn from the federal Substance Abuse and Mental Health Services Administration’s National Survey on Drug Use and Heath, and other sources include the Centers for Disease Control and Prevention’s Behavioral Risk Factor Surveillance System and the Bureau of Labor Statistics.

As Mahmud points out, “We do see a spike in marijuana use in Colorado and other other states that’s above the national average. But we’re not seeing it replicated in other charts.”

Take the number of heroin deaths in Colorado. It’s a subject of great concern within the state, but Mahmud notes that the rate here is actually below the national average.

As for cocaine use, the Colorado rate is above the national average and has risen to a small degree in the past year or so. But Mahmud emphasizes that the number of Colorado users was higher nationally prior to marijuana legalization, too, and remains well under 3 percent — far below the state’s figures for marijuana use.

A similar scenario can be seen in Colorado regarding binge alcohol use in the past month. The numbers are higher than the national average but don’t mirror marijuana usage in any substantial way.

One part of the study looks at tobacco use: Colorado’s rate is significantly below the national average and on a steady decline. As Mahmud sees it, one type of smoking hasn’t increased another kind.

Also addressed are other issues frequently mentioned by opponents of marijuana legalization — harm to young people and problems on the job.

For Mahmud, these results undermine the theory that legal pot contributes to a wide range of societal ills.

“The hypothesis was that if marijuana is truly a gateway drug, we’d see a spike in the use of other substances in addition to a spike in marijuana use,” he says. “We should have seen spikes all over the place. But when we looked at the data, the corresponding spikes didn’t exist. And because of that, it led us to the conclusion that there isn’t a strong correlation between marijuana use and the use of other substances.”

Nonetheless, Mahmud doesn’t argue that the results are definitive. He said LiveStories will continue to mine data on the subject and encourages suggestions about other sources — including ones touted by those who criticize progressive cannabis policy — in case “there’s something we missed.”

However, he goes on, “The data that we looked at is comprehensive nationally and from very good sources. And it didn’t show a correlation between marijuana use and other substance abuse.”