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5 Cannabis Myths That Should Go Up in Smoke

As Maryland Legalizes Recreational Marijuana, UMD Experts Weed Out Misinformation

By Allison Eatough ’97

employee walks through cannabis growing room

Compliance manager Justin Garcia walks through one of the cannabis growing rooms at SunMed Growers, in Warwick, Md. As the state readies for the legal sale of recreational marijuana on Saturday, UMD public health experts warn of the risks of the drug, particularly to developing brains.

Photo by Jerry Jackson/The Baltimore Sun/Tribune News Service via Getty Images

More Marylanders are expected to toke up—or in the case of edibles, chomp down—starting on Saturday, when the state legalizes recreational marijuana. But bluntly speaking, the products available today aren’t the heirloom herbs popular with Cheech and Chong or the potent pot of Snoop Dogg’s gangsta rap heyday.

Even as studies show cannabis-derived products, including THC-infused oils, gummies and cigarettes, can help treat forms of epilepsy, vomiting due to chemotherapy, and weight loss associated with HIV/AIDS, the drug itself has gotten more powerful over the past 25 years and can harm developing brains and lead to addiction, said two University of Maryland experts on youth substance abuse.

Two-thirds of voters in November favored expanding cannabis beyond medicinal use for adults 21 and older, putting Maryland on the path to become the 24th state to approve the shift. It allows people to possess up to 1.5 ounces of marijuana and grow as many as two cannabis plants at home, as long as they are out of public view.

Supporters of the new law say it will generate tax revenue, reduce violence and trafficking associated with sales of illegal drugs and promote equity in the cannabis industry.

Already, 10% of Marylanders are using marijuana, according to a March study by what’s now known as the Maryland Cannabis Commission, including 15% of high schoolers.

Amelia Arria, professor of behavioral and community health and director of the School of Public Health’s Center on Young Adult Health and Development, and Malinda Kennedy, assistant research professor and project director for The Maryland Collaborative, a network of Maryland colleges, universities and partners working to reduce underage and excessive college drinking and related problems, are concerned about a surge in those statistics.

“Some might believe that if cannabis is legal, it is safe,” Kennedy said. “However, that is just not the case, especially for young brains.”

As municipalities, industry advocates and health officials grapple with the implications of the new law, Arria and Kennedy clear the smoke on five common cannabis myths.

Myth: Cannabis is not addictive.
Arria said individuals who start using cannabis during youth or adolescence and those who use regularly have an increased risk of cannabis use disorder, a term for being unable to stop using the drug, even if it causes health and social problems in their lives.

People should be on the lookout for symptoms of this disorder in themselves or others, including craving cannabis, forgoing activities with friends and family to use cannabis, using it in high-risk situations such as while driving, or needing to use more of the drug to get the same high.

“People who experience cannabis use disorder can feel isolated and unheard because people incorrectly believe cannabis can’t be addictive,” Kennedy said. “We need to have sympathy for these people who are really struggling.”

Myth: Cannabis is natural, so it’s harmless to the body.
The concentration of THC, the psychoactive component in cannabis, has risen dramatically since 1999, thanks to genetic engineering; the plant is now nearly five times stronger, and its products even more so. Research, said Arria, shows higher-potency products have been linked to faster transitions to addiction and more serious mental health consequences, including psychosis in some people.

Smoking cannabis can also damage lung tissues, small blood vessels and developing brains, which don’t fully mature until age 25. A 2021 study of teens found cannabis use was associated with thinning of the prefrontal cortex, the part of the brain responsible for focus, decision-making, memory and problem-solving. Several other studies on the effect of cannabis on brain structure in teens reported similar findings.

Myth: Cannabis cures anxiety.
While cannabis can provide a mellow high for some, it can make others irritable. In addition, someone who has anxiety will still have anxiety when the drug’s effects wear off, Arria said.

“Cannabis use, like drinking alcohol, can mask anxiety symptoms temporarily, but it doesn’t treat the real causes,” she said. “Continued use of cannabis can actually increase anxiety in the long run.”

Using cannabis as a “go-to strategy” also reduces opportunities to learn and practice healthy coping skills with a clear head, Arria said.

Myth: Cannabis does not impact driving ability.
Driving under the influence of cannabis is illegal. It’s clear that the drug can slow reaction time, impair coordination and distort perception, even as research continues on how the method or amount of THC ingested impacts driving impairment.

“Although there is some variability in details of the studies and more research is needed, the bottom line for all of them is that it is not safe to drive under the influence of cannabis,” Kennedy said.

The Maryland Cannabis Administration, which oversees Maryland’s cannabis industry, recommends waiting at least six hours after using cannabis to drive.

Myth: Cannabis helps you sleep better.
Studies suggest THC may have a short-term sleep benefit, but its regular use disrupts circadian rhythms and rapid eye movement (REM) sleep, the deepest phase of sleep, said Arria.

Regular cannabis users may experience sleep problems if they cut back on their use, but this is actually a sign of withdrawal, not an indication that cannabis was helping with sleep, she said.

It can take up to two months of abstinence before normal REM sleep recovers, she added.

“Researchers are still working to better understand how cannabis impacts sleep for better or worse,” Kennedy said. “So, in the meantime, if someone is suffering from sleep problems, we would recommend that, with the help of their doctor, they look into more reliable options that are available.”



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