It may be older users who are driving the rise in cannabis use in the US Volha Shukaila/SOPA Images/Shutterstock
Cannabis is the most used illicit substance in the world, with an estimated 219 million people using it in 2021. Nowhere is it more popular than in the US and Canada.
In 2021, 52 million people aged 12 and older in the US used cannabis, roughly 1 in 5 people in this age group. Those figures have been inching upwards over the last few decades – a fact that isn’t that surprising given the expanded access to legal (or quasi-legal) cannabis and a shift in attitudes towards the drug.
The uptick in use, ease of access and increased social acceptability of the drug have some experts – and parents – worried, particularly about increased use among adolescents. That is with good reason: a growing body of evidence suggests cannabis use during adolescence may affect brain development, potentially increasing the risk for developing various mental health conditions or substance use disorders.
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Yet so far, fears of a surge in adolescent cannabis use haven’t been borne out by the data. Results from the National Survey on Drug Use and Health, an annual survey conducted by the Substance Abuse and Mental Health Services Administration, showed that rates of past-month cannabis use among teens aged 12 to 17 in the US have actually declined over the past 20 years: from 8.1 per cent in 2002 to 4.8 per cent in 2021.
Instead, the increase in cannabis use is being driven entirely by adults. The 12 to 17-year-old crowd now has the lowest rates of past-month cannabis.
Some health professionals are sceptical that we are seeing the full picture when it comes to teen use, however. “I cannot believe that that is true, that it has not gone up,” says clinical psychiatrist Ryan Sultan at Columbia University in New York. “Every other piece of information would suggest it should be going up.”
For instance, we know that more people now think of cannabis as a relatively benign substance. “In general, when perceptions of things move toward safety… that increases the likelihood” of use, says Sultan. Legalisation of recreational cannabis has also been linked to increased uptick in use of the drug.
Sultan isn’t ruling out the possibility that expanded legalisation has diminished the drug’s allure, or that kids are choosing to wait until they are older to use weed. If those things turn out to be true, it would be welcome news, he says. But he thinks it is more likely there is a missing piece to the puzzle, hidden by a lag in the data collection.
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