Marijuana Questions: Teens Ask, Scientists Answer


question mark with yellow background

Every year, the National Institute on Drug Abuse usually hosts a Chat Day during National Drug and Alcohol Facts Week.

During this event, some the nation's top scientists answer drug-related questions from students across the country. 

Check out the questions the teens asked about marijuana during 2019's Chat Day, along with the answers from scientists.  


Question: My friend smokes marijuana everyday, how will that affect her? Is there any way I could help her stop? 

- 309 

Answer: Thank you for being such a caring friend!! Animal studies suggest that ---because the teen brain is still developing---early use of marijuana alcohol or tobacco may alter the brain's reward system, putting teens at higher risk of using other drugs. In addition, using marijuana puts children and teens in contact with people who use and sell other drugs, increasing the risk of additional drug use. Getting off drugs and quitting varies, depending on the person and the drug. If you want to ask about getting substance abuse treatment for your friend, call 1-800-662-HELP, 24/7. Or you can go to to find information about treatment centers in your area. 

- Mary Kautz 


Question: Does smoking marijuana cause cancer? 

- Wiley Wildcat 

Answer: Hey Wiley- It's actually still not known whether smoking marijuana leads to lung cancer. However, there does appear to be a link between marijuana use in adolescence and increased risk for an aggressive form of testicular cancer.  

- Emily Einstein 


Question: What different effects do CBD and THC have on a teenagers brain/behavior? 

- HWP4Y 

THC and CBD oil


Answer: Great question. We know much more about THC than we do about CBD. THC is the main ingredient in the cannabis plant that makes you high. It works by attaching to "cannabinoid receptors"--proteins found in the brain and the body that are part of a signaling system involved in pain, appetite, emotions, memory, nervous system development, immune function and more. THC is responsible for most of the effects we associate with cannabis--particularly in youth--memory problems, increased risk for addiction and other psychiatric problems. CBD is much less well understood in terms of how it works and what its long term effects are. It doesn't make you high, and doesn't lead to addiction. Recently the FDA approved a CBD medication--Epidiolex-- for treating severe epilespy in young children. One of the main concerns with CBD is that unregulated products are not what they say they are or are not manufactured safely. 

- Tisha Wiley 


Question: Why are teens less afraid of weed and why are adults so worried? 

- batroomcomunity 

Answer: Hi Batroomcomunity! Thanks for participating today and for the great question. Teens may want to experiment but NIDA-funded research shows that when usage starts during the teen years, marijuana use is associated with impaired thinking, memory, and learning functions. It is also associated with a number of mental conditions, including psychosis (schizophrenia), depression, anxiety, substance use disorders, and suicidal thoughts or attempts. However, it is not yet clear whether marijuana use directly causes these issues or just makes them worse. Currently, the strongest evidence is for the link between marijuana and psychosis in persons with a preexisting genetic or other vulnerability. Marijuana intoxication can, in rare cases, produce a temporary psychosis. Some teens might try to use marijuana to make them feel better but in the long run, it can cause problems, including misuse. 

- Kristen Huntley 


Question: If you were in middle/high school and have been smoking weed for 4 years (7th-10th) what effects?



Answer: Hi Dr.doofenshmert 
Interesting username :) 
Heavy and regular use of marijuana at any age is detrimental to health causing cognitive problems such as reduced memory, concentration and/or motivation. However, in the case of middle/high schoolers the effect of cannabis can be worse since the brain is still under development (the brain matures in the mid 20's). Cannabis interferes with normal brain development in youth and research has shown some of the bad effects are not reversed even after one stops using cannabis (e.g. lower IQ, risk for psychosis). You can find out more at

In essence, marijuana and a teenager's brain are best never acquainted! 

- Geetha Subramaniam 


question: What are the effects of thc? 

- bluefacebaby 

Answer: THC is the active ingredient in marijuana. THC produces changes in mood and perception that some users find desirable. However, THC can also induce adverse effects including increased heart rate, irregular heart beats, psychotic thinking and uncontrollable vomiting. The following link provides more detailed information Marijuana: Facts for Teens booklet: 

- Michael Baumann 


Question: What's a dab? 

- Chapoopoo 

gorilla glue shatter

Answer: Thanks for the question, Chapoopoo! Dabs are various forms of high grade hash (marijuana), usually made with a process involving butane, and concentrated into a smokable oil. The amount of THC (the psychoactive component of cannabis) in a dab is highliy concentrated and very strong. You can find out more about marijuana and addiction here: 

- Tisha Wiley



Question: Why is weed a drug if it is a plant? 

Charlie Hartman 


Answer: Hi Charlie 
It is a great myth that plant based products are safe or benign - case in point - cannabis. There are several substances that are derived from plants that can be dangerous/poisonous or addictive. Tobacco, opium derived from the flowers of poppy plants, and cocaine derived from leaves of the coca plant (commonly grown in South America) are all examples of drugs (i.e. addictive substances) derived from plants and are addictive and can be harmful. So plant based products are not necessarily safe. 

Geetha Subramaniam 


Question: What is an effective solution to helping a friend quit smoking without looking like a snitch? 

- moses 


Answer: Dear Moses, It is great that you are concerned about your friend's health. Tobacco, marijuana, and nicotine all impact the body and brain negatively. If you are concerned about your friend, you could let them know in a nonjudgmental way how smoking is harmful. You can educate yourself and share your concern about how they could be, or are being negatively affected. You can also talk with them about seeking help from a trusted adult like a teacher, coach, or parent. More information on smoking and marijuana is available at: 

- Redonna Chandler 


Question: If you do marijuana is it definite that you will end up doing more drugs?

- ethanhuffman 


person rolling marijuana jointAnswer: Hi ethanhuffman - this is a great question! Everyone has a different experience with drug use. Some people can use marijuana, and never feel the need to use other drugs. Other people start their drug use with marijuana (or cigarettes), and they do start using other drugs. It is not definite at all; but there is a risk that using one drug may lead to other drug use, too. 

- Michelle Leff