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Marijuana Use: Science Facts Regarding Teen Use and Health

Marijuana teens

In my work with adolescents, marijuana issues are occasionally discussed.  Sometimes, the teen has been using.  However, often she or he reports that other friends and classmates are regular users.  Frequently, I am told that it is easier for teens to buy marijuana than alcohol or cigarettes.

Marijuana is a common drug that is used by teens and adults around the country and world

It is the third most commonly used drug in the United States after alcohol and tobacco. According to a 2012 study, 6.5 percent of high school seniors reported smoking marijuana daily.  Additionally, 31 percent of young adults (ages 18 to 25) reported using marijuana in the last month. More than a third of Americans have used it.  Also, roughly 7 percent of the population are “regular users.”  Medical marijuana is now legal in 26 states.  Recreational use of marijuana is now legal in 9 states.  Finally, it is more common to see or smell marijuana in public places.

Because of its popularity and increasing legality, many people believe that marijuana is safe to use.  I’ve heard teens and adults say that is not habit forming or “not really bad for you.”  Some people even argue that it is even healthy, since it is used medically to treat some health concerns.

If people are going to use marijuana, they should educate themselves first

They should rely on information that is peer-reviewed, and based on scientific research.  It is ok to listen to friends and read what the internet says.  But, people also need to verify information from scientific sources.

Below are some important facts about marijuana, based on scientific research

How it works

Marijuana causes a temporary “high.”   The active chemical is TCH, or delta-9- tetrahydrocannabinol.  When smoked or eaten, it changes a person’s perception and/or causes a surge of euphoria.  Short-term, people often report feeling relaxed or happy.  Long-term there are consequences of regular marijuana use, particularly for teens and young adults.

Today’s pot is not your grandparents’ pot

Marijuana potency (how strong it is) has steadily increased over the past few decades. In the early 1990s, the average THC content was roughly 3.7 percent. In 2014, it was 6.1 percent, which is almost twice as strong.

Eating it is not safer than smoking it.  In fact, eating THC-rich hash oil extracted from the marijuana plant delivers very high levels of THC. The average marijuana extract contains more than 50 percent THC, with some samples exceeding 80 percent. As a result, consequences of marijuana use could be worse than in the past.

Marijuana is not good for your brain

The adolescent brain continues to grow until the early twenties.  During this period, the brain is more very vulnerable to the effects of drugs. Marijuana affects nerve development.  Also it impacts neural activity in the brain.   The more marijuana use, the less the brain works well.

Regular use of marijuana causes thinking problems, poor attention, decreased impulse control. It also causes memory problems.  Even worse, it decreases your intelligence (APA, 2014).  That’s right. People who are addicted to marijuana lose an average of six IQ points by adulthood, according to  a 2012 longitudinal study of 1,037 participants who were followed from birth to age 38.  That a very large difference.  It is large enough to cause life-altering learning disabilities in language or solving problems.  It is a big deal.

Outside of supervised medical use, smoking marijuana it is not good for your body

Marijuana has carcinogens, or cancer-causing chemicals.  It has three-times more retention of tar and five times more retention of carbon monoxide in your lungs than tobacco smoking. That means that marijuana can be more dangerous than tobacco when it comes to cancer risk.

It IS addictive!

Scientific evidence supports that long-term marijuana use WILL lead to addiction, particularly in teens and young adults.  Young people who start experimenting with marijuana are two to four times more likely to develop addiction in the first two years than those who start in their adulthood.  Studies suggest that 9 percent of people who use marijuana will become dependent on it, rising to at least 17-35 percent in those who start using in their teens.

Fast Fact: Smoking marijuana can be more dangerous than tobacco when it comes to cancer risk.

People report to feel relaxed when they smoke marijuana.  But, they also report long-term negative effects.

Recent research has found that marijuana can increase stress, anxiety, and social anxiety.  Increased depression also occurs.  If that isn’t enough, marijuana use is also linked to symptoms of schizophrenia in people who have a genetic tendency for mental illnesses.

Most people who use marijuana believe it helps them feel less anxious or depressed.  Scientific research finds that the opposite occurs.   People who use drugs to avoid painful feelings and stressful situations are less likely to fully process these experiences.   As a result, they experience even more long-term stress and depression.

In other words, by using marijuana to avoid feeling bad, they actually make it harder for their brain and body to deal with their feelings.  Thus, these folks are stuck in a negative cycle of more drug use and unsuccessful emotional processing.   Sometimes, these negative patterns lead to even more dangerous conditions, such as other illicit drug use, severe depression, and suicidal behaviors.  It can also make it harder to function at jobs, at school, or in relationships.

It makes driving dangerous

Alcohol intoxication is not the only cause for accidents. In fact, marijuana is the illicit drug most frequently found in the blood of vehicle crash victims.

Increased concentration of TCH in the blood makes driving ability worse.  It significantly impairs judgment, motor coordination, and reaction time.  As a result, marijuana smokers are less likely to control the vehicle and can fatally endanger their lives (and the lives of their passengers), for many hours after use.  Crashes and traffic problems cause legal, social, and financial problems.

It can interact with your current medications

According to the Mayo Clinic, marijuana may interact with many prescribed medications. Side effects include anxiety, depression, fatigue, drowsiness, and lower blood pressure.  These effects are particularly concerning if you take mental health medications for anxiety, depression, or ADHD.  Potential medications of concern include benzodiazepines, barbiturates, antidepressants, stimulants, and alcohol.  Always let your physician know if you use marijuana and take medications, even if it is embarrassing.  They are there to help.

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Metrik, J., McGeary, J.E., Rohsenow, D.J., Aston, E.R., Kahler, C.W., & Knopik, V.S. (2015). Marijuana’s Acute Effects on Cognitive Bias for Affective and Marijuana Cues. Experimental and Clinical Psychopharmacology, 23(5), 339-350.

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