Scientific Research Debunks Common Pro-Pot Arguments | Opinion

In the debate over marijuana legalization, supporters of the pot industry often resort to poor arguments, outdated studies and hyperbole to "bust marijuana myths."

First and foremost, advocates of marijuana legalization routinely deny that the drug acts as a "gateway" to more dangerous substances. While it's true most people who use marijuana don't go on to use other drugs, the vast majority of those who have tried heroin or cocaine, or prescription drugs used marijuana first. Yes, they also "drank milk first," as some sarcastically exclaim, but there is no mechanism connecting milk and drug use.

By contrast, research has indicated that marijuana users are 2.6 times more likely to abuse opioids, perhaps because of the way the brain craves more highs.

Some misconstrue the "gateway theory" to imply that use of marijuana causes a person to use heroin immediately afterward. This is not normally the case. The truth is simply that people who use drugs do not normally use just one.

Furthermore, a peer-reviewed analysis of several studies released recently in the prominent journal Addiction found marijuana users faced a 2.8 times greater likelihood of beginning opioid use than non-users. Researchers also found marijuana users to be 2.5 times more likely to transition to opioid addiction. Citing several studies on this matter, the NIH concluded "These findings are consistent with the idea of marijuana as a 'gateway drug.'"

Second, legalization supporters claim there is zero evidence of a connection between marijuana and crime. For example, in a recent Washington Post op-ed, former Post reporter Christopher Ingraham eagerly dismissed a possible connection based largely on the work of one researcher with financial ties to the marijuana industry (a fact Mr. Ingraham did not disclose), and an eight-year-old research review that doesn't consider newer findings.

While it is difficult to say whether marijuana legalization causes crime, plenty of research suggests a strong connection. A 2019 study concluded the existence of marijuana dispensaries in Denver were significantly associated with increased crime. According to another new report, marijuana-related crimes in Colorado are up since legalization.

Marijuana dispensaries are prime targets for robberies—given the massive amount of products that sit just behind the counter, which can later be sold in underground markets.

And in "legal" jurisdictions, the underground market is thriving. Several states and cities have seen marijuana crime increases since legalization, including Los Angeles, Oregon and Colorado. In its 2019 National Drug Threat Assessment, DEA found that states with the highest marijuana removals were pot states or those bordering them.

Legalization gives cover to drug traffickers, including violent transnational criminal organizations, like the notorious Sinaloa Cartel.

Third, legalization advocates dismiss the effects of marijuana potency. Today's marijuana is up to 50 times stronger than marijuana used in the past, causing people to do more than just "chill out." The average THC concentration—which determines potency—was 3 percent only a few decades ago. Now we are seeing products with 99 percent. The products are now in the form of edibles, dabs, waxes and shatter. A 2020 study found 90 percent of these products sold as "medicine" featured THC levels in excess of 15 percent—which is roughly two to three times higher than the amount shown to provide relief for neuropathic pain.

Scientists have confirmed the harmfulness of these products. The Lancet found regular users of high-potency marijuana are five times more likely to develop schizophrenia or psychosis. In fact, almost six dozen peer-reviewed studies confirm the link between high-potency marijuana and psychosis.

Marijuana legalization protest
Demonstrators march in the annual NYC Cannabis Parade & Rally in support of the legalization of marijuana for recreational and medical use, on May 1, 2021 in New York City. - New York Governor Andrew Cuomo signed legislation legalizing recreational marijuana on March 31, 2021, with a large chunk of tax revenues from sales set to go to minority communities. Angela Weiss / AFP/Getty Images

A 2018 Dutch study shines light on the dangers of high potency. THC strength in the Netherlands doubled from 9 percent in 2000 to 20 percent by 2004. This increase was followed by a rise in individuals seeking treatment for marijuana issues. When the potency declined in 2015, treatment admissions for marijuana issues fell. All told, the researchers estimated that for every 3 percent increase in THC potency, one person in 100,000 would seek first-time treatment for marijuana. These findings led the Dutch to cap marijuana potency.

In 2020, Vermont became the first state in the nation to implement a marijuana potency cap. And in Colorado—where a shocking report found that the use of marijuana dabs among the state's youth has risen five-fold and the use of marijuana vapes has doubled since 2017—lawmakers recently moved to explore the possibility of a potency cap. Higher-potency marijuana unequivocally exacerbates many of the harms of marijuana use, both in the short and long term, but translates to a significant money maker for the industry. No wonder it consistently opposes such sensible regulations.

The ever-increasing variety of marijuana products can mask danger for users. Today's marijuana selection is a dizzying array of flavors, strengths and strains. Their differences are touted by the pot industry as if they are as palpable as a Granny Smith apple versus a Red Delicious.

The reality is that what is sold at a pot shop is often not as advertised. Legalization states have delegated regulatory lab analysis to for-profit marijuana testing labs. Pot cultivators must pay private labs to conduct safety tests and potency analysis on their product prior to it being sold. Across the country, labs have been accused of fraud due to the inflation of THC potency, passing moldy marijuana off as safe and making up results entirely—as pointed out in my book Smokescreen: What the Marijuana Industry Doesn't Want You to Know. Such lab corruption is widespread; the incentives to cheat are high and enforcement is lacking.

Finally, legalization supporters often argue as if they have science on their side. The truth is exactly the opposite: every single major medical association opposes legalization. Often citing non-peer reviewed papers, or papers in low-quality journals, legalization advocates' cherry picking does a severe disservice to those interested in the truth.

For example, pot supporters claim the "jury is out" on the connection between lax policies and road safety. Research from the Highway Loss Data Institute found that the legalization of marijuana coincided with an increase in collision claims. In Colorado, traffic fatalities have increased more than 30 percent since 2013, coinciding with a rise in instances of traffic fatalities in which the driver tested positive for marijuana. In all, 20 percent of traffic fatalities in Colorado in 2018 involved a driver who tested positive for marijuana use, most likely recent use.

In Canada, where marijuana is legal nationwide, a report issued last week found charges for marijuana-impaired driving rose 43 percent since legalization.

Some legalization supporters tout a now-debunked study claiming a 25 percent reduction in opioid deaths in states with medical marijuana. But Stanford researchers updated the study in 2019 and found when extended to include states legalizing marijuana between 2010 to 2017, legalization was associated with a 25 percent increase in opioid fatalities.

We must stop perpetuating the false notion marijuana is an answer to opioid abuse. Research has shown marijuana users are in fact more than twice as likely to abuse prescription opioids and more likely to require higher doses of opiate medications for pain. Another study found marijuana use among those in recovery from opioid use disorder led to relapse within less a week, finding marijuana increased users' urges to use opioids.

But don't take my word for it. Read the position papers of the American Medical Association, the American Academy of Pediatrics and other prominent health organizations.

At a time when millions of Americans are turning to the CDC and the NIH for advice on COVID-19, the health warnings about marijuana from these very same institutions are being ignored in favor of claims delivered by pot profiteers.

Why the double standard?

Dr. Kevin Sabet is a former senior drug policy advisor to the Obama administration and currently serves as president of Smart Approaches to Marijuana. His latest book, Smokescreen: What the Marijuana Industry Doesn't Want You to Know, was published on April 20 by Simon & Schuster and is available everywhere books are sold.

The views expressed in this article are the writer's own.

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