These questions were answered by more than 50 individual scientists and science writers with expertise in addiction. To get as many answered as possible, responses were written quickly based on the personal background and knowledge of each expert. Please note that there was not a secondary review or proofreading of each fact, and if readers have questions or comments about any response, they can ask further questions.

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does smoking marijuana have any positive effect on you?

-her508310, Illinois

Hello Her508310,

Marijuana, like tobacco, is a plant that contains many hundreds of chemicals, including potentially pesticides (which kill insects). One of these chemicals, cannabidiol, may be effective for preventing seizures in some children, but researchers are still studying this. Most of the chemicals in marijuana are harmful both physically (they have negative effects on a person's brain) and because they can affect a person's judgment and their ability to drive safely, for example. For more information, check this out:


-Roger Little

does taking drugs make you suicidal?

-YG, Illinois

Illicit drugs raise the risk of suicide. More than half of people who die by suicide have alcohol or drugs in their blood at the time of death! If you are already depressed or having suicidal thoughts, get help and don't use drugs or alcohol. If you have suicidal thoughts while taking a drug, stop taking the drug, and get help right away from a friend or trusted adult. People having suicidal thoughts can also get help by calling the National Suicide Prevention Lifeline at 1-800-273-TALK (8255) anytime, 24/7 (you'll be connected to a skilled, trained counselor at a crisis center in your area).

-Joshua Gordon

Does the alcohol is dopping?


Hi dadio,
I am not sure what you are asking about...
If you mean "is alcohol use dropping?" the answer is Yes. Recent surveys do show that alcohol drinking, particularly in teenagers and young adults is decreasing.
On the other hand, if you mean "is alcohol used in doping?", i suppose the answer could be yes. Alcohol can slow down our reflexes and performance and if used before sports or other activities, it can casue impairment.
Hope this helps!!
- Vijay

-Vijay Ramchandani

Does the current scientific literature reflect the assertion that habitual marijuana use is correlated with a reduced IQ?

-Pajamadunes, California

Wow--excellent question. Yes and no. The original study that showed this indicated that many years of chronic use (and cannabis dependence) was associated with a reduced IQ (and numerous other factors were ruled out as causal). Some more recent studies have failed to replicate the finding and suggest instead that some other environmental factor is associated with reduced IQ and cannabis is not critical for the decline. Its always difficult to know conclusively what the answer is because you can't do the definitive experiment which would require you to randomize people to heavy use or not, holding all other factors equal. But the recent non-replications covered much shorter time frames, so it still may be the case that long term (30 years) persistent cannnabis use, begun in adolescence, does cause a reduced IQ. We hope to answer that question more definitively with an ongoing study: ABCD

-Dave Thomas

Does the usage of marijuana cause cancer??

-Ye'07, Illinois

Still not sure--it has been associated with a fairy rare form of testicular cancer, and the jury is still out on lung and other airway cancers.

-Susan Weiss

does the way you take the drug effect how bad it is

-peyton, Maryland

Hello Peyton,

Drugs are dangerous because if you start taking them and develop an addiction, then you feel like you have to keep using them, even if they're damaging your health. For instance, some people who develop an addiction to opioid pain medicine would never have dreamed they'd ever inject heroin, but that's what happens for some people, and they can't help themselves. So taking a drug one way is no guarantee it won't escalate to something more dangerous like injection -- which can result in the spread of diseases like HIV, hepatitis, and other infections. For more information, see this:


-Roger Little

does using marijuana while bodybuilding actually help?

-Hat, Illinois

hi hat
of course not.

-Heather Kimmel

does vaping affect your brain ?

-jamyia, Illinois

Hi there Jamyia! Thanks for your question. We don't know all the effects of vaping because these devices haven't been around for long. However, we do know that most vaping devices contain nicotine. Like other drugs, nicotine increases levels of a neurotransmitter called dopamine. One thing we worry about with vaping is that they may lead to nicotine addiction and this might cause some people to start using regular cigarettes, which can cause cancer. Check out this blog post for more information:

-Mary Kautz

Does vaping cause Erectile Disfunction?

-E, Illinois

Hi E -,
What an interesting question. Unfortunately there is not evidence currently if vaping causes erectile dysfunction. However, smoking cigarettes can damage DNA in men's sperm. There are currently no e-liquids approved to treat erectile dysfunction. For more information about e-liquids and vaping visit

-Suzanne Lim

Does vaping get you a better chance to start smoking or doing any other drugs?

-Patrick Star, Illinois

Hi PS - There are scientific studies showing that teens who vape are more open to trying cigarettes. We are still studying whether vapers are more likely to become smokers, but even the increased openness to smoking is concerning. Smoking by teens has been falling every year for the past decade, and that is an important trend that needs to continue. Check out the infographic about vaping from the 2018 teen drug use survey of 8th, 10th and 12th graders:

-Kevin Walton

Does vaping have the same effect on you as marijuana?

-benn, Illinois

Good question, benn! Not necessarily. Vaping solutions contain a variety of chemicals that may include some of the chemicals found in the marijuana plant. Because most people who vape do not include those chemicals, they are being exposed to different substances that would not be expected to produce the same physiological effects.

-Michele Rankin

Does vaping liquids without nicotne harm you?


Hi elrabbid, great question. There are a lot of chemicals in the aerosol, or vapor, that comes out of an e-cig. This includes propylene glycol, glycerol, and flavor chemicals. Some of these chemicals are known to be harmful to the lungs, and most have not been shown to be safe for inhaling. Unless someone is trying to stop smoking, people should not start using them. For more info,

-Kevin Walton

does weed have effects on the body such as health problems?

-TY, New Mexico

Marijuana can produce a number of health problems. The active ingredient in marijuana, THC, produces adverse effects on the heart, brain and other organs. THC causes increased heart rate and palpitations (i.e., irregular heart beats), which could contribute to serious heart dysfunction. THC leads to impaired thinking and decision making, which could contribute to loss of behavioral control. Long term use of marijuana is associated with an increased risk for psychotic disorders such as schizophrenia, a devastatng brain disease. In short, the risks posed by marijuana are substantial.

-Michael Baumann

does weed relax the body?

-TY, New Mexico

Great question. The active ingredient in marijuana, THC, can produce different effects on the body, depending upon the dose and each individuals' response. In general, THC increases heart rate and can cause palpitations (i.e., irregular heartbeats). Marijuana can produce anxiety, panic attacks and hallucinations. So, contrary to popular belief, marijuana does not relax the body.

-Michael Baumann

Does wine really help your heart, or does it harm your body?

-4176, Illinois

The latest research suggests that small amounts of alcohol, whether from wine or beer or spirits, could make it less likely someone has a heart attack. But it can increase the chance of cancer, injuries, and other bad outcomes. So it looks like it's not worth it to drink alcohol for health.

-George Koob

Does your sexual performance decrease if you do hard drugs


Yup- long term use of heroin or cocaine is associated with diminished sexual desire and performance.

-Suzanne Lim

Doesn't LSD have positive affects?

-drugsalcohol, Illinois

Hi drugsalcohol,
Good question
There are quite a few reputable researchers that believe so, and there has been sort of a renaissance in the past decade or so in the area of hallucinogenic research in general and LSD and psilocybin in particular. It will take more time to have a clearer picture of the potential therapeutic and spiritual benefits of these drugs, but I think the scientific community is slowly moving in that direction. Stay tuned.

-Steve Grant

Don't psycadelics have some possible positive affects?

-drugsalcohol, Illinois

Thanks for the question. There are some clinical research studies going on that are studying the possible uses of some drugs like MDMA in some limited circumstances. It's important to keep in mind that studies like this are done with a lot of supervision and in very controlled and safe environments. Psychedelics are mostly used for recreational purposes at relatively high doses; doing this can have a lot of unpredictable effects.

-Roger Little

Dr Dave, what drugs are most addictive

-Chungus, Illinois

All drugs of abuse are addictive, and its hard to say which is the most addictive. It depends on a lot of things. For example, people have a real hard time quitting smoking. But a lot of smokers smoke all day long, and that is likely part of why they are hard to quit. For more info, check out the NIDA for teens website on the different kinds of drugs and their affects on the body:

-Steve Grant

Drinking while pregnant can cause fetal alcohol syndrome, and doing drugs while pregnant can lead to an addiction for the baby. What are the effects of smoking marijuana while pregnant? Also, are there any addictive properties in marijuana?

-I am Spartacus, Missouri

Hi, there is evidence that using marijuana while pregnant--whether smoked or injested another way--can be harmful for the fetus. Using marijuana while breastfeeding is also a bad idea. Yes, marijuana is addictive; among those who start at a young age, 17% become addicted. The best thing is to avoind using it!

-Emily Jones

Drugs are bad for my health and me growing? Right?

-chamneess_a, Oregon

Hi Cham,
When you are still growing, you are more vunerable bad effects of drugs. And if these drug effects impact your developemnt, those change could stay with you the rest of your life. We are doing a lot of research on this topic, but we are very concerned about the impact of drug on younger people, as they are still growing and developing.

-Dave Thomas

El Sueve pasa a liguilla?????


no se. vos que pensas?

-Ruben Baler

ELLLOOOOO. Okay so I see stars are very hard to obtain. I get that. Smh. BUT, what effects do drugs have to the body and mind when driving. Do certain ones make you more impaired than others? What do you do if you are in a situation where the driver is on some type of drugs and they are beginning to not be able to drive.

-Georgiana, Illinois

Georgiana - great question! Almost all drugs that are not prescribed by a doctor can affect the brain in ways that make driving unsafe--including marijuana, opioids, cocaine, amphetamine, benzodiazepines, etc. To drive a care safely, your balance, motor skills, coordination, perception, ability to pay attention, reaction time, and judgment must all be in good working order. Drugs may impair all of them, even when taken in small amounts. Don't get in the car with someone who is using a drug. If you are already in the car, see if you can tactfully encourage them to pull over.

-Amy Goldstein

Exactly how many diseases does alcohol cause?

-DS, Florida

The World Health Organization estimates that alcohol causes or contributes to more than 200 diseases and types of injuries. By their calculations, alcohol is responsible for 6 out of every 100 deaths worldwide each year. That adds up to more than 3 million people.

-Dave Thomas

first of all goodmorning, my first question is what happens if you inhale drugs at a young age?


Good morning, wigettaisreal! This is a great question. Drugs are chemicals. When someone puts these chemicals into their body, either by inhaling or smoking, they tap into the brain's communication system and tamper with the way the brain sends, receives, and processes information. Different drugs—because of their chemical structures—work differently. Since the brain is not fully developed until the mid twenties, inhaling chemicals at a young age can negatively affect brain function. Impaired brain function can persist even after the person has stopped using drugs. Here is more information about drugs and brain development Teen Brain, a Work in Progress.

-Katia Howlett

Given that nearly every adult out there, including a current justice of the Supreme Court, drank in high school, are the effects really as big as anti-fun industries want us to believe?

-nico, California

Thanks for your question, Nico.
We have learned a lot about alcohol and how it affects the developing teen brain over the past few decades. We know that the risk of developing a problem with alcohol is higher if people start drinking before the age of 21. We also know that alcohol can disrupt how the brain develops and leads to problems with attention, memory and reasoning. It is just best to wait until at least the legal drinking age of 21 before drinking.

-Marsha Lopez

Good afternoon, I am curious to know how bad is it for a person to start drinking at a young age, such as 16 or 17 years old. Have a nice day.

-4o reich,

Great question. We've learned a lot in the last few years about the risks of drinking at such an age. We know that the risks of developing an alcohol use disorder are much higher if someone starts drinking anytime before the age of 21.
We also know that the brain is still developing at this point in life and that alcohol can disrupt brain development in ways that lead to lingering problems with memory and attention. It's simply best to wait.

-Emily Einstein

Greetings fellow EPIC gamers, is it ok to lotion my body with CBD lotion?

-BigKid459, Illinois

Hi BigKid -- It is very unlikely that CBD lotion will cause any harm, or benefit. The science on CBD suggests that it isn't well-absorbed through the skin. If you're using it for its possible anti-inflammatory purposes, for a rash for example, it could be helpful, since CBD has anti-inflammatory properties. One thing to be cautious about is that many products sold as containing CBD (or other compounds from marijuana) actually contain very little if any of it.

-Kristen Huntley

has anybody ever died by ONLY smoking marijuana?

-g, Illinois

Hey g. Marijuana doesn't cause overdose death the way that drugs like alcohol or opioids do. Marijuana-related deaths are most likely to be the result of injuries, car accidents, etc.

-Heather Kimmel

Has anyone ever overdosed by smoking only marijuana?

-lyonslions, Illinois

You may have heard that nobody has ever died from an overdose of marijuana. However, a person can certainly overdose on a drug without dying, and marijuana is no exception. If a person uses a large amount of marijuana, perhaps by smoking too much of a high-potency marijuana or eating a lot of food products containing marijuana, they can experience very negative consequences, such as paranoia, severe anxiety, and even psychotic symptoms, which is when a person loses touch with reality. You can learn more about overdoses here:

-Steve Gust