Recent Research Casts Doubt On Claim That Marijuana Is Harmful To Brain

A marijuana plant is displayed during a 420 Day celebration on 'Hippie Hill' in Golden Gate Park on April 20, 2018 in San Francisco, California.
Justin Sullivan / Getty Images

Although marijuana is legal in some U.S. states and all of Canada, politicians continue to sometimes turn to the drug for blame. Most recently, the Dayton, Ohio mass shooting was blamed on marijuana and drag queens by Republican Ohio lawmaker Candice Keller.

Despite its hazy reputation, Truthout reports that recent research continues to debunk claims that marijuana harms the brain.

Marijuana was previously associated with lower cognitive functioning thanks to a 2012 study, which claimed that cannabis use in early adolescence was significantly associated with a decrease in IQ points — eight, in particular — by middle age. But a critique of the study suggested that the IQ decline was consistent with socioeconomic differences across those studied, and later, better-controlled studies reportedly failed to replicate the findings of the 2012 study.

A 2017 study by researchers at the University of Colorado examined the effect of marijuana exposure and alcohol ingestion on the structure of the brain in both adults and adolescents. The data suggested that while there is a connection between alcohol use severity and changes in lower brain matter in both adults and adolescents, no associations were found between such changes and “past 30-day cannabis use” in adults or adolescents.

The Truthout report ends with a call for a change in the approach to marijuana in the face of the facts.

“It is time for politicians to reject the unsubstantiated ‘reefer rhetoric’ and fear-mongering of the past and move forward to amend U.S. cannabis laws in response to the emerging science, public opinion and the plant’s rapidly changing cultural status.”

It appears that politicians may be catching on. Forbes reports 2018 as “The Year Politicians Realized People Love Cannabis Reform,” noting that both Illinois and Connecticut elected governors that year that were receptive to legalizing marijuana. In addition, New York Governor Andrew Cuomo is “seriously debating” marijuana legalization in the state, where possession of small amounts is currently decriminalized.

Although Forbes reports that politicians have historically trailed the public when it comes to supporting cannabis reform, the publication notes that some are still shifting their views as time passes.

“Between winning elections and converting opponents, cannabis reformers have more allies in office than ever before,” the report reads. “With continued pressure from activists, 2019 will be the year those allies turn their campaign promises into law.”

Per The Motley Fool, there are currently 33 states that have legalized medical marijuana. Of these states, 11 have legalized the consumption and/or sale of recreational cannabis. In addition, six states are currently trying to legalize recreational marijuana in 2020: Arizona, Arkansas, Florida, Missouri, New Jersey, and South Dakota.