Cannabis: the risks, especially for teens
Risky SubstancesKey points
- Addiction develops in about 9% of users, and about 17% of those who start as teens.
- Teen use: 37% higher risk of depression and 3.5 times higher risk of suicide attempts.
- It raises the risk of psychosis, especially with frequent use of high-potency products.
- It impairs attention, memory and coordination and is dangerous when driving.
What the research shows
Addiction and brain development. A review in the New England Journal of Medicine by NIDA director Nora Volkow concluded that about 9% of people who use marijuana become addicted, rising to about 17% of those who start in adolescence. Regular use during adolescence is linked to impaired brain development and poorer school outcomes, and use raises the risk of psychosis in vulnerable people (Volkow et al., 2014).
Depression and suicide. A meta-analysis of 11 prospective studies with more than 23,000 participants found that cannabis use before age 18 was linked to a 37% higher risk of depression and a 3.5 times higher risk of suicide attempts in young adulthood (Gobbi et al., 2019).
What parents can do
- Talk early and calmly, with facts rather than scare tactics.
- Ask what your teen thinks and listen.
- Explain that legal for adults does not mean safe for developing brains.
- Store any cannabis products, especially edibles, locked and out of reach.
- Watch for changes in mood, sleep, grades or friends, which can also signal problems such as problematic smartphone use (Sohn et al., 2019).
Frequently asked questions
If cannabis is legal in my state, is it safe?
Legal does not mean safe. Today’s products are often far more potent than in the past, which raises the risk of dependence and psychosis.
Is cannabis use during pregnancy safe?
No. The CDC and ACOG advise against using cannabis during pregnancy and breastfeeding.
Sources
- Volkow et al. (2014). Adverse Health Effects of Marijuana Use. New England Journal of Medicine 370(23):2219-2227. doi:10.1056/NEJMra1402309
- Gobbi et al. (2019). Association of Cannabis Use in Adolescence and Risk of Depression, Anxiety, and Suicidality in Young Adulthood. JAMA Psychiatry 76(4):426. doi:10.1001/jamapsychiatry.2018.4500
- Sohn et al. (2019). Prevalence of problematic smartphone usage and associated mental health outcomes amongst children and young people: a systematic review, meta-analysis and GRADE of the evidence. BMC Psychiatry 19(1). doi:10.1186/s12888-019-2350-x
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