Researchers from Dartmouth’s Geisel School of Medicine, whose crest is pictured above, and other academic medical institutions, surveyed 2630 14- to 18-year-olds via Facebook who live in states that have legalized marijuana for medical use (MMJ states), recreational use (RMJ states), and not legalized the drug (NMJ states).
MMJ and RMJ states vary in what they allow, and the researchers wanted to learn if different provisions influence when adolescents begin marijuana use and which provisions may result in increasing use among young people.
The researchers say it is crucial to understand how marijuana legalization laws affect youth because they are more vulnerable to the drug’s harmful effects. Chronic use during adolescence has been associated with impaired brain development, educational achievement, and psychosocial functioning, as well as an increased risk of developing addiction.
Legalization has spurred the development of new marijuana products with higher potencies, such as marijuana-infused foods called edibles and electronic vaping devices that enable a user to inhale the psychoactive ingredients of tobacco and marijuana without the smoke.
Edibles sold in most legal states lack safety standards or products regulations and are marketed in ways that are attractive to youth, the researchers note. These factors are contributing to the sharp increase in marijuana overdoses among young people. Vaping devices are becoming increasingly popular among middle school and high school children who use them to vape marijuana more often than adults. Moreover, data show adolescents are vaping high-potency marijuana products whose impact on neurodevelopment is unknown but concerning because they may place youth at higher risk for psychosis.
The researchers find that youth in legalization states are twice as likely as those in nonlegalization states to have tried vaping. Moreover, youth in legalization states with high dispensary density are twice as likely to have tried vaping and three times more likely to have tried edibles than youth in nonlegalization states.
The kind and duration of marijuana legalization laws also impact youth. Youth in MMJ states are significantly more likely to have tried vaping and edibles than youth in nonlegalization states, and youth in RMJ states are significantly more likely to have tried both than youth in MMJ states. Youth in legal states that allow home cultivation are twice as likely to have tried edibles (but not vaping) as their peers in legal states that prohibit home grows. States with the oldest legalization laws also see increases in youth lifetime vaping and edible use.