There has been considerable debate in recent years over the risks of cannabis use, particularly among young people. While many advocates have argued that cannabis has few adverse effects and can even be beneficial in certain cases, scientific research has shown that this drug can cause a wide range of negative outcomes, including cognitive impairment and dependence. Studies have also found that the younger a person starts using cannabis, the higher the risk of developing these kinds of problems down the road.

Cannabis use among teenagers is widespread. In fact, cannabis is now the most commonly used illicit drug in the world. In the 2021 Monitoring the Future Survey, drug use trends showed that, in 8th, 10th, and 12th grade, daily cannabis levels were either at or near the highest level recorded since 1991, and in 2018, more than 11 million young adults reported using cannabis. Although data shows that approximately 4.1 million Americans over the age of 12 reported using cannabis in 2017, the majority of those people were between the ages of 12 and 25.

These kinds of statistics are alarming, particularly given what we know about the effects of cannabis on the developing brain. Studies have shown that extended use of cannabis during adolescence can lead to changes in brain function and development, causing cognitive and behavioral problems later in life. Furthermore, cannabis can negatively impact a teenager’s mental health, leading to an increased risk of anxiety and depression.

Given the significant risks associated with teenage cannabis use, it is clear that action must be taken to address this issue. Prevention efforts aimed at educating young people about the dangers of using cannabis and other drugs must be enhanced. Treatment services for teens who are struggling with substance abuse or addiction must be provided. With comprehensive strategies and support from all sectors of society, we can work together to stem the tide of teenage drug use and make our communities healthier and safer.


What are the effects of cannabis on young brains?

The effects of cannabis on a young person’s brain are still being researched. However, significant evidence points towards negative outcomes. Most researchers agree that there is a definite potential for cannabis to harm the developing teenage brain, in both short- and long-term ways.

Some of the short-term effects of cannabis on the young brain are:

  • Difficulties focusing and paying attention
  • Problems with memory and concentration
  • Lack of interest in academics and/or personal hobbies
  • Increased aggression and risk of violence when under the influence
  • Increased risk of using alcohol or other drugs
  • Increased risk of unsafe sexual behaviors
  • Worsening of underlying mental health conditions, including mood changes and/or suicidal thinking
  • Increased risk of psychosis
  • Interference with prescribed medication(s)

Long-term use of cannabis can lead to:

  • Addiction and/or dependency (using cannabis more often than intended, having cravings, suffering from withdrawal symptoms, etc.)
  • Decreased motivation, which can impact school and/or work performance
  • Lower intelligence
  • Mental health problems, such as schizophrenia, depression, anxiety, anger, irritability, moodiness, and risk of suicide


Does cannabis affect young people differently than it affects adults?

Many researchers believe that cannabis affects young people differently than adults because their brains are still developing. Others argue that the effects of cannabis are similar for everyone, regardless of age. Most experts agree that cannabis use during adolescence comes with a greater risk of developing problems later in life.

To better understand how cannabis affects the brain itself, some researchers have turned to controlled drug experiments that, for ethical and scientific reasons, can only be performed on animals. For example, Kuei Y. Tseng, based at the University of Chicago in Illinois, investigated how rats respond to tetrahydrocannabinol, or THC, the main psychoactive ingredient in cannabis.

When a person uses cannabis, THC quickly passes from the lungs into the bloodstream. The blood carries the chemical to the brain and to other organs throughout the body. THC acts on specific brain cell receptors that ordinarily react to natural THC-like chemicals. These natural chemicals play a role in normal brain development and function.

When studying young rats, Tseng found that, during a specific window of adolescence, exposure to THC or similar molecules delays the maturation of the prefrontal cortex, a region of the brain involved in complex behaviors and decision-making. The disruption alters how that area of the brain processes information later on when the rats have grown into adults.

In another study, postdoctoral researcher Mikhail A. Piskunov and his colleagues, also at the University of Chicago, found that adolescent rats exposed to THC had changes in the structure of their hippocampus. The hippocampus is a region in the brain that contributes to memory formation. Piskunov observed that these changes to the hippocampus were still present in adulthood.

These two studies and other relevant research point to alarming potential risk for long-lasting damage to the brain, resulting from exposure to THC as a young person. These findings suggest that cannabis use during adolescence may have profound and persistent effects on the brain, which could lead to a lifetime of problems.

So, what does all this mean for young people?

Simply put: cannabis is not harmless. Levels of THC in today’s cannabis are often 4 or more times higher than in earlier decades. In the United States, the question of safety for young cannabis users has taken on particular urgency recently, due to the relaxing of legal policies and to changing societal views towards the drug. Since 2012, many states as well as the District of Columbia have legalized the use of recreational cannabis by adults, and though cannabis consumption is still illegal for minors, the changing legal and commercial landscapes may make cannabis products more accessible and attractive to teenagers. 

We as a society must educate ourselves to become aware of the potential dangers of cannabis use on young people.. Despite its growing perception as a relatively harmless drug, cannabis can have serious long term effects. Teens and adults must become aware of the dangers of cannabis use on developing brains.