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Legalization of marijuana and youths’ attitudes toward its use

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The legal status of marijuana has changed a great deal during the last 4 decades. In the United States, several states have legalized the use of marijuana to treat several medical conditions. Some states have decriminalized marijuana possession, and several have legalized marijuana for recreational use by adults. These changes have contributed to a growing misperception among young people that marijuana is harmless or not as risky as other illicit substances.

In this article, I explore the effect the legalization of marijuana has had on young peoples’ attitudes toward its use.

Marijuana use among adolescents

Among adolescents, marijuana is the most commonly used illicit substance, after alcohol.1 According to data from the 2019 Monitoring the Future Survey, while past month, past year, and lifetime marijuana use among 8th and 10th graders remained steady from 2018 to 2019, daily marijuana use among these adolescents increased.2 This survey also reported increases in adolescent marijuana vaping from 2018 to 2019.2 Further, the percentage of adolescents who think that the regular use of marijuana is risky has been trending down since the mid-2000s.2

Youth substance use rates depend on numerous factors, including legal status, availability, ease of access to the substance, and perception of harm.3 Although the legalization of marijuana for recreational use has been for adults only, based on rates of tobacco and alcohol use in adolescents (both of which are legal for adults), the legalization of marijuana is likely to have implications for adolescents.4

Adverse effects among adolescents

During adolescence, the brain is still developing, and marijuana use during this time could cause decreased cognitive functioning, especially executive functions.4 Marijuana use by adolescents also has been associated with4,5:

  • an increased risk of mental health disorders, including depression, anxiety, and psychosis, particularly among adolescents at higher risk, such as those with a family history of psychiatric illness
  • a decline in school performance
  • an increased school dropout rate
  • an increased risk of marijuana de­pen­dence
  • an elevated rate of engaging in risky behaviors.

Factors by which the legalization of marijuana might increase its use among adolescents include4:

  • perceived decreased risk of marijuana use
  • increased availability
  • lower cost
  • decreased fear of legal consequences of marijuana use.

Increased parental use is an indirect way in which legalization of marijuana for adult recreational use might increase use in youth.

Continue to: What the evidence says

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