Statistics on Marijuana Use in Teens

More than 48 million Americans over the age of 12 have used marijuana in the last year according to the 2019 National Survey on Drug Use and Health, making it the most common illicit drug used in the United States. Roughly 22.2 million use it every month.

Marijuana is also surprisingly available to youths, even in middle school. In 2019, nearly one-third of 8th graders said it would be "fairly easy" or "very easy" to get marijuana. Nearly 60% of 10th graders and over three-quarters of 12th graders said the same.

The marijuana legalization movement has played a role in sending mixed messages to young people that marijuana is safe because "it's medicine" or "it's legal." This leaves it up to parents to help set things straight. By understanding the risks, dangers, facts, and statistics on teen marijuana use, you can better address the issue with your teen.

Teen Marijuana Use Statistics

One of the best ways to prepare yourself to talk about marijuana use is to learn the latest statistics, particularly as they relate to teens. Here's what we know about teen marijuana use:

• More than one in three high school students (37%) have used marijuana, with one in five (22%) admitting to using this drug within the past month.
• The older a teen is, the more likely they are to have tried marijuana. Almost 30% of 10th graders admit to having tried marijuana while this percentage increases to 44.5% for those in the 12th grade.
• In general, more males than females use marijuana. Although, some schools have found that usage among male teens is declining while usage rates are remaining steady for female teens.
• Teens identifying as nonbinary or not heterosexual are more likely to try marijuana than cisgender or heterosexual teens, especially if they are distressed about their gender identity.
• As far as marijuana form, most teens prefer to consume this drug by smoking it, accounting for one-half of its use. This is followed by dabbing (one in eight), consuming edibles (one in nine), vaping (one in 15), and drinking marijuana beverages (one in 30).
• Between 2017 and 2020, the rate of high school seniors vaping marijuana more than doubled, with over a fifth reporting vaping THC within the past year. Roughly 8% of 8th graders also reported vaping marijuana at least once in the past 12 months.
  

How Marijuana Affects Teen Brains

A teen's brain does not finish developing until roughly 25 years of age. Using marijuana before this development is complete can impact their brain's structure and function.

Though results are mixed, some research has found that teens who regularly use marijuana alter the connectivity of the pathways in their brain, and some of their brain regions are smaller as well—particularly those associated with memory, learning, and impulse control.

Abnormality in brain structure may be even greater in female teens that use marijuana when compared to males. One 2012 study also found that participants who had begun persistent cannabis use in their teens lost an average of eight IQ points, even after controlling for years of education.

Risks of Teen Marijuana Use

Some view teen marijuana use as "not a big deal." However, there are certain risks associated with using this drug in your younger years.

Mental Health Issues

People who start using marijuana in adolescence are more likely to experience early-onset psychosis. Usually, the heavier the usage, the more severe the symptoms. Although the direction of causation is still unclear, a common theory is that marijuana can exacerbate pre-existing vulnerability to psychosis, "tipping the scales" for people who otherwise wouldn't have developed symptoms.

Marijuana use may also precede depression. According to a study published in JAMA Psychiatry, cannabis use during the teen years is linked to higher rates of major depression as well as suicidal thoughts later in life.

Cognitive Problems

Teen marijuana use can be particularly problematic on a cognitive or brain-based level because it can impact the adolescent's:

• Attention or focus
• Decision-making
• Inhibition and impulse control
  
• Learning ability
• Memory
• Verbal fluency

Some of these cognitive issues are thought to occur due to marijuana changing the chemical structure of the brain. Others are suspected to be a result of the drug being toxic to brain tissue.

Addiction

About one in six people who start using marijuana as a teen become addicted. People who begin using marijuana before age 18 are also four to seven times more likely to develop a marijuana use disorder than adults.

In those that use marijuana every day, somewhere between 25% and 50% develop an addiction. As with most addictive substances and behaviors, the rewarding effects of marijuana (such as the "marijuana high") are central to it being addictive.

Impaired Driving

Driving while under the influence of marijuana can double the risk of a car accident in young drivers, and the risk is even greater when small amounts of alcohol are also consumed.

Researchers have found that marijuana use affects the driver's concentration and ability to perceive time and distance, which may lead to poor speed control, drowsiness, distraction, and the inability to read road signs accurately.

Marijuana is the most common illicit drug found in drivers who die in accidents—around 14% of drivers—and sometimes in combination with alcohol or other drugs.

Declines in School Performance

Students who smoke marijuana are more likely than their non-using peers to get poor grades and drop out of high school. Dropping out of school comes with a variety of consequences. This includes a higher risk of poverty, lower earning capacity, and sometimes even poorer physical health.

Teen marijuana use can also impact in-school behaviors. Some studies have found that problems at school are more common in teens using marijuana, particularly when those teens are male.

Other Health Risks

Marijuana has many negative health effects. For instance, its smoke contains 50% to 75% more of certain cancer-causing substances than cigarette smoke. Although evidence is mixed, some studies suggest that heavy marijuana use could increase the risk of lung cancer.

When teens smoke or vape marijuana, they put their lungs at risk. As of February 18, 2020, there have been 2,807 cases of e-cigarette or vaping product use-associated lung injury (EVALI) across the U.S. Most of the EVALI cases have been linked to devices containing tetrahydrocannabinol (THC), the ingredient in cannabis that causes the high.

Medical Marijuana and CBD

Recreational marijuana use is legal in 18 U.S. states—but only for adults 21 and older, not for teens. Not even the most adamant legalization advocates propose making it legal for children to use marijuana.

Laws for medical marijuana vary from state to state, but in most states, medical marijuana use for children or teens is only given for "qualifying medical conditions." In Washington, for example, qualifying conditions include cancer, chronic kidney failure, and traumatic brain injury.

The problem with medical marijuana is, even in states that allow it, this drug is not regulated by a governmental agency. Therefore, it's uncertain whether the marijuana being purchased is safe. It's also unknown how strong or pure it is.

Cannabidiol (CBD) is another substance that is derived from the cannabis plant. Yet, the only CBD-containing product currently authorized by the Food and Drug Administration (FDA) for use in teens is Epidiolex, a drug used to help treat rare and severe forms of epilepsy.

Talking to Teens About Marijuana

Don't wait for your teen to bring up the subject of marijuana. Start a conversation today. Find out what your teen knows already and be prepared to share the facts.

Hold ongoing conversations about the dangers of marijuana use. Discuss changes in the law or bring up the subject when there are stories about marijuana in the news.

Take steps to build credibility so your teen will value what you have to say. Discuss the dangers of using marijuana and make sure your teen fully understands the risks—even the risks associated with occasional substance use.

Find out what your teen is hearing from other sources too. Friends, social media, and other websites often promote marijuana, and they may give your teen false information about drugs. It's important for you to be able to provide factual data.

A Word From Verywell

Knowing the statistics on marijuana use can help you when discussing this topic with your teen. Understanding the effects of teen marijuana use also enables you to share this information so your teen knows the impact that marijuana use can have on their growing bodies.