Marijuana and Adolescent Brain Development

On Tuesday, March 6, I attended a talk by Ruth A. Potee, MD, on marijuana, adolescent brain development and teen risk-taking. The talk, which was held at the Concord Middle School, covered many topics related to addiction, but I will focus on what she had to say about teens and marijuana.

Our brains are not fully developed until we hit the age of 24 or 25. If someone experiments with substances while their brain is still developing, the risk of addition greatly increases. According to Dr. Potee, many of those addicted to alcohol, marijuana and nicotine first used the substances between the ages of 12 and 14. She says that 40% of kids who begin drinking at age 15 become alcoholics. But if someone postpones their use of a substance until the age of 21, their odds of getting addicted are only 7%. If they wait until age 23, the odds of addiction drop to 2%.

If a teen uses marijuana regularly, their brain’s development may be impeded. Studies have shown that regular use of marijuana can result in a decrease of eight IQ points, but, as Dr. Potee noted, these were studies in which the marijuana had a THC potency of 3%. Today’s marijuana is much more potent — its THC potency can reach 30%, while THC concentrates, which can come in the form of waxes, oils or tinctures, have potencies of 50% to 90%.

The good news, she says, is that when it comes to tobacco and alcohol, most kids today are making smart decisions. They are receptive to being educated about the harm from cigarettes, and tend to think that smoking is gross, not cool. The bad news is that their receptiveness does not carry over to marijuana. Pot, they think, is medicinal. They hear that it’s safer than tobacco. That you can’t OD on it. They perceive that it’s safer to be driving under the effects of marijuana than alcohol. (Some maintain that being stoned makes them a better driver.) And, of course, they see it’s legal in Massachusetts. So as their sense that the harm from using marijuana goes down, their use of it goes up. In fact, 2017 marked the first year that teens were more likely to use pot than cigarettes.

Dr. Potee said that marijuana is a neurotoxic drug, (meaning it is poisonous or destructive to nerve tissue) and the multi-billion-dollar marijuana industry is geared to addicting as many young people as possible. And it seems to be achieving that goal. Sugar has long been considered the most addictive substance in the world, with nicotine second. For decades, she says, the addiction rate for marijuana was 9%, meaning that roughly 1 in every 10 people who tried it became addicted. But as marijuana users start younger, and as marijuana gets more potent, the addiction rate for marijuana today has soared to 30% — a rate higher than nicotine.

Which is why, during her talk, she called legalized marijuana “a public health mess.”

Ruth Potee is a board-certified family physician and addiction medicine physician at Valley Medical Group in Greenfield, MA. In addition to practicing full-scope family medicine, she is currently the Medical Director for the Franklin County House of Corrections, the Franklin Recovery and Treatment Center and the Pioneer Valley Regional School District as well as the Chair of the Healthcare Solutions of the Opioid Taskforce of Franklin County.  She was named Franklin County Doctor of the Year by the Massachusetts Medical Society in 2015 and is the Chair of the Department of Medicine at Baystate-Franklin Medical Center.  Dr. Potee engages communities in discussions surrounding substance abuse through her series of talks.

And, I might add, she is a hell of a speaker. The part of her speech which I have covered here doesn’t hint at the insights she shares (some of them humorous) from her perspectives of a family doctor and a mother. Catch one of her talks if you can.