Young people in legal weed states are using less cannabis than teens from previous generations, but new research is reporting that nicotine vaporizers like Juul could be having their own gateway affect.

A new study published in one of the country’s most respected medical journals is reporting a correlation between the recent proliferation of nicotine vaporizer use by teenagers and youth cannabis consumption. 

First reported by CNN, the new research was published in the peer-reviewed publication JAMA Pediatrics under the title “Association Between Electronic Cigarette Use and Marijuana Use Among Adolescents and Young Adults.” After digging through 20 recent studies of youth nicotine and cannabis consumption, the authors concluded that young people who use nicotine vaporizers like Juul are more likely to experiment with cannabis.

“Adolescents have a brain that’s still changing and developing,” said Dr. Nicholas Chadi, the study’s lead author. He added that when the young brain is exposed to addictive substances like nicotine, “[it] tends to be sensitized to other substances; it tends to seek a thrilling, rewarding sensation. And so other substances like marijuana become more appealing.”

In America’s recent experiment with cannabis legalization, youth consumption has been a hot button topic from the start. In the half decade since Colorado kicked off adult-use cannabis sales, though, legal weed states have continually reported unchanged or decreasing rates of teen pot use

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But even with marijuana consumption down, researchers like Chadi still view cannabis as a threat to young people. In a brain-melting twist of prohibitionist arguments, Chadi reversed the decades-old (and debunked) gateway drug theory that pot is bad because it leads users to other, worse drugs. Instead, he claimed that nicotine is dangerous not because it is incredibly addicting, but because it could lead to cannabis use. Chadi then cited outdated claims about youth brain development and potential damage from marijuana to defend his argument.

“We can’t think of e-cigarettes as a less-harmful alternative to cigarettes with adolescents,” Chadi said, in part because “just like cigarettes, e-cigarettes increase your risk of using marijuana, and marijuana, we know, has several implications and negative health consequences in adolescents.”

Still, despite his own personal feelings, Chadi and his fellow researchers were clear to note that the results of their study represented only a correlation between youth vape use and cannabis consumption, and not a causal relationship.

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