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  • Writer's pictureDr. Luisa Bryce

5 reasons marijuana is detrimental to the teen brain


Marijuana has been known as the gateway drug of teen substance use for decades. It’s often thought of as less harmful and consequential than other drugs because it’s “natural” and now legal in many parts of our country. In the U.S. and other first world nations, marijuana is the second most commonly used substance among teens after  alcohol. Why? Because it’s easy to obtain and attitudes about the risk of regular use are becoming more lackadaisical by the year. Teenagers are increasingly associating regular marijuana use as “no big deal”. Marijuana’s increasing popularity has sparked the attention of researchers- which has led to new studies showing that marijuana may be far more detrimental to the teen brain then previously believed. Here are the top 5 reasons (in my opinion) to keep your teen away from the green stuff:

1. Marijuana IS Addictive:

The widespread belief that you can’t get addicted to marijuana is false. In fact, 1 in 6 teens who use marijuana daily will become addicted (as compared to 1 in 11 adults who use) (Degenhardt, et al., 2012; Hall and Degenhardt, 2009).

2. It Really Does Make You Dumber:

Regular use of marijuana in adolescence predicts an 8-point drop in IQ from age 13 to 38 years. Marijuana impairs brain development and daily use may cause irreversible brain changes. Eight points may not sound like a lot, but it’s actually pretty substantial (IQ is measured in terms of Standard Scores, which have a mean of 100 and a standard deviation of 15) (Meier et. all, 2012).

3. You May Just Die Sooner:

– Teens who drive under the influence of marijuana face almost double the odds of involvement in a fatal car accident (Asbridge, Hayden, & Cartwright, 20012).

– Emergency room visits related to marijuana increased 52% from 2004 to 2011 in the U.S. This is largely due to the availability of marijuana edibles, as the amount of THC in edibles is not regulated by the Federal Drug Administration.

4. You May Start Believing People on TV are Sending You Messages:

Regular use of marijuana in the teenage years doubles the risk of developing psychosis in adulthood (Manrique-Garcia, 20012; Moore et. al., 2007).

5. You May Start to Freak Out, Long-Term:

As if we didn’t have enough to worry about in this day and age, daily use of marijuana in adolescence triples the chance of developing a clinically significant anxiety disorder in adulthood (Degenhardt, 2013).

If you think your teen may have a problem with drug use, talk to your pediatrician. He or she can refer you to local resources in your community. If you have questions, comments, or want a list of the references cited in this post, please feel free to contact us at Harmony At Home.

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