Because the brain isn’t fully developed until age 25, she explained that during adolescence and into young adulthood, the brain over-produces neuronal connections, which manage communication. During adolescence and young adulthood, the brain gets rid of the receptors that aren’t needed anymore.
For example, we are born with the ability to roll our Rs, but if we don’t roll our Rs, over time, we lose the ability to do so.
“By putting cannabis into our bodies and using substances [before 25] then we are significantly more likely to become addicted because they get reinforced,” said Halpern-Felsher.
While cannabis can be addictive and mind-altering at any age, she added that if adolescents and young adults inhale, smoke, or eat any addictive substance, they are much more likely to become addicted because the brain is still developing and looking for ques about what to keep or not keep.
The risk of developing cannabis use disorder is also higher in people who use marijuana more often.
“Increased cannabis use can affect tolerance levels, making teens who use cannabis less sensitive to tetrahydrocannabinol (THC), meaning more THC is needed to feel the same effects,” Robin Christensen, chief of the substance and addiction prevention branch at California Department of Public Health (CDPH), told Healthline.
She noted that cannabis today is much stronger than in past decades because modern cannabis plants contain high amounts of THC.
“The higher the THC content, the stronger the effects on the brain and behavior,” said Christensen.
More than 20 states in the US have legalized marijuana for adults and nearly 40 have legalized medical marijuana. However, the US government still considers cannabis an illegal Schedule I drug, which means it’s categorized as a drug with no currently accepted medical use and a high potential for abuse, according to the Drug Enforcement Administration.
“When a product like cannabis is legalized, for teenagers and young adults, the message is it must be okay; it must be safe. The reason for legalization is political, it’s the tide swinging, it is to decriminalize it, but it is not at all a message that it’s safe, particularly for an adolescent or young adult,” said Halpern-Felsher.
There is also the misperception that cannabis is safer than cigarette smoking.
While some experts say that nicotine is the most addictive substance available right now, Halpern-Felsher said when it comes to brain development, lung health, and heart health, there’s not much difference between cannabis and nicotine.
“That’s true of not just primary use but secondary smoke whether in the form of a blunt or joint, but also in the form of e-cigarettes or vaping,” she said. “The addiction is similar. Anything you inhale into your body can cause lung damage and can also cause damage to your heart.”
While big tobacco companies have been vilified, making teens well aware of the dangers of smoking cigarettes, the cannabis industry has yet to be denounced in the same way.
Not understanding the potency of edibles is another dangerous component of cannabis that people, especially teenagers, often don’t understand.
Halpern-Felsher said while edibles will not cause lung disease, they can still cause addiction and mental health issues, as well as cannabinoid hyperemesis syndrome (CHS), a condition that causes nausea, vomiting, and abdominal pain after using cannabis.
“We’ve seen this a lot in the emergency room because young people don’t understand the dosage involved,” she said. “Edibles take longer to get into your body and your brain…about 20 minutes to a couple of hours, whereas inhaled, can take a few seconds or half a minute and so what happens with teens, they think they’ll feel the effect of a high quickly and they don’t so they keep taking more and more edibles and by the time they feel the effect, they’ve actually taken too much.”
While people most likely do not die from CHS directly, they can feel extremely ill and require hospitalization.
Lack of awareness surrounding the details of cannabis comes down to not talking about it enough, said Halpern-Felsher.
“One study we published, we talked to teens and they said, ‘You don’t talk to us enough about cannabis and so we think it’s okay,’” she said.
To inform youth about the dangers of underage cannabis use and how it can impact their social and emotional well-being later in life, CDPH launched the campaign Mind Over Marijuana.
“The message to teens is…really helping them understand that [cannabis] use can affect brain development and within that it affects your memory, and increases stress and anxiety. A lot of teens think it helps with those, but it doesn’t,” said Halpern-Felsher.
In addition to messaging targeted toward teenagers, CDPH also initiated the Let’s Talk Cannabis campaign to encourage parents, guardians, and the community to have open, two-way conversations with teens about cannabis.
“Our research shows that parents are the number one influence on a teen’s behavior. Having conversations about cannabis with teens early on and often can help prevent youth cannabis use,” said Christensen.
While it can feel like your teen isn’t listening to what you say, Halpern-Felsher said the reality is they want to understand what’s going on and they want to learn from you.
“The key is for parents to make sure teens feel heard and seen so it’s not a lecture; it’s let’s have a two-way conversation,” she said. “It’s asking: what do you know about pot or weed or marijuana? Let me tell you what I learned or know.”