Facts about Marijuana and Youth Health

In Denver, marijuana use is only legal for individuals 21 years or older. Research shows that the tetrahydrocannabinol (THC) in marijuana can harm the developing brain and cause problems even after marijuana use ends. For this reason, it is not recommended that youth or adolescents even consider using marijuana until 25 when the brain is fully mature.

Marijuana and Youth Health Facts
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Marijuana Use among Denver Youth

Marijuana use among Denver youth is higher than both state and national averages.

  • In 2013, 27% of Denver high school students reported use within the past 30 days, compared to 20% in Colorado and 23% in the United States. 
  • Youth report using marijuana more frequently than tobacco. 
  • Of Colorado high school seniors who have used marijuana, more than one out of three started before age 15.

How Does Marijuana Affect Youth Health?

The tetrahydrocannabinol (THC) in marijuana specifically affects the areas of the brain—pleasure, memory, thinking, concentration, sensory and time perception, and coordinated movement—which continue developing until 25. 

Research suggests that regular use of marijuana during adolescence may result in: 

  • Learning problems
  • Memory issues
  • Future use of alcohol, tobacco and other drugs
  • Lower math and reading scores
  • Mental health issues, such as impaired emotional development, depression, anxiety and psychotic symptoms (not knowing what is real, hallucinations and paranoia)

Marijuana affects everyone differently. There are some common short-term effects people using marijuana report, which are mentioned in the Marijuana and Your Health section of our site.

Why is Marijuana so Appealing to the Developing Brain?

The adolescent brain craves pleasure but isn’t mature enough yet to weigh risks. This may result in youth using marijuana because they crave the good feelings, or the “high,” without having the ability to think about potential long-term consequences as an adult would.

Not everyone who uses marijuana develops a marijuana addiction, or cannabis use disorder. However, research shows that one in six people who use marijuana as a teen will develop an addiction (compared to one in 11 people who start using marijuana as an adult.)

Programs like the Substance Abuse Treatment and Education (STEP) Program at Denver Health offer supportive programs to help young people address and manage substance abuse addictions, including cannabis use disorder.

Talking about Marijuana Use During Adolescence is Important

While the majority of Denver high school students (72%) did not use marijuana within the last month, experimentation with substances like marijuana, alcohol and tobacco during teenage years is common. Parents play a crucial role in preventing, delaying and/or reducing the use of these substances.

Local data show that when a child perceives that his or her parent approves of marijuana use, that child is three times more likely to use marijuana, compared to a child who perceives that his or her parent disapproves of marijuana use 67% versus 21%).

Talking directly to youth about responsible marijuana use is recommended so youth can make informed decisions and practice responsible behavior if/when use occurs. Some tips for parents include: 

  • Talk to your children. It is never too early to start to have an age-appropriate, non-judgmental discussion. Be clear and specific about your family expectations about marijuana use. 
  • Be a good role model. Children learn from their parents/guardians. Demonstrate positive behaviors by not using or driving under the influence of marijuana or other substances around your children. 
  • Safely store all marijuana products. Some products, particularly edible ones like gummy bears or brownies, may appeal to children. Store all marijuana products in child-resistant containers and lock them away like you would any medication or cleaning supply. 

Data and Educational Resources