Is JUUL Bad For You?

By Andrew Yocum, MD
Medically reviewed checkmarkMedically reviewed
April 5, 2022

Cigarette smoking is the leading cause of preventable death among Americans, killing more than 480,000 people in the United States each year. 

Electronic cigarettes, including one brand name called JUUL, are often marketed as a healthier alternative to traditional cigarettes, particularly to young adults.

That marketing has worked: While 6% of all U.S. adults use e-cigarettes, 17% of 18-29 year olds polled by Gallup in 2021 said they’d used one in the past week.

But using an e-cigarette, also called vaping, is still hazardous to your health.

In this article, I’ll explain what JUUL and vaping are, and which substances they contain.

I’ll also cover the side effects and risks associated with JUUL and vaping, and when you may want to talk with a doctor or healthcare provider about your options.

Considering quitting vaping? Chat with a medical professional today to discuss your options.

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What is JUUL or Vape?

Both JUUL and “vapes” are electronic cigarettes, also known as e-cigarettes. Sometimes called “e-hookahs,” “vape pens,” or “electronic nicotine delivery systems (ENDS),” these devices come in many different shapes and sizes.

Some may look like traditional cigarettes or pipes, while others may resemble everyday items, like USB flash drives or pens.

The JUUL brand of e-cigarettes is shaped like a USB drive. 

Most e-cigarettes contain a battery element that heats a liquid—often containing nicotine and other flavorings and chemicals—that then produces an aerosol that is inhaled by its user.

People who are not pregnant may use JUUL or vapes as a substitute for traditional cigarettes as a mechanism to limit or ultimately quit smoking.

But no US government body has approved vaping as a tool for quitting smoking. And data shows that e-cigarettes have been increasingly marketed to teens and young adults—and that early use of e-cigarettes may cause long-term damage to their health.

Is vaping different from JUUL?

No. Vaping and JUUL are both forms of e-cigarettes.

JUUL is a specific brand of e-cigarettes that is often marketed to teens and young adults.

What Substances Are In A JUUL or Vape?

Unfortunately, it’s not always possible to know which substances are in a JUUL or vape.

A recent study from the Centers for Disease Control and Prevention (CDC) found that 99% of e-cigarettes sold in the US contain nicotine.

Even when these products are marketed as having zero nicotine, data shows that they do contain nicotine.

One JUUL pod contains as much nicotine as a pack of 20 regular cigarettes, a substantially higher amount of nicotine than the previous generation of e-cigarettes.

Many of the chemicals in e-cigarettes may be harmful to human health.

Chemical components often found in e-cigarettes include:

  • Nicotine: The same highly addictive chemical compound found in cigarettes.
  • 1,3-Butadiene: A chemical that has been found to cause certain blood cancers.
  • Benzene: Can cause cancer, especially leukemia. 
  • Diacetyl: A chemical linked to serious lung disease.
  • Heavy metals: Including nickel, tin, and lead.
  • Ultrafine particles: When inhaled, these particles can land deep into the user’s lungs.
  • Volatile organic compounds (VOCs): These can cause eye, nose, and throat irritation, headaches, nausea, liver damage, and damage to the kidneys and nervous system.

Side Effects

Because e-cigarettes have only been in use for a few years, researchers are still working to understand their long-term health effects.

But the long-term side effects of nicotine are well-documented.

These can include:

  • Addiction: Research clearly shows that nicotine is highly addictive. Because it’s highly addictive, stopping can be very difficult and cause withdrawal symptoms. Nicotine withdrawal symptoms may include cravings, increased anxiety, irritability, restlessness, difficulty concentrating, depressed mood, frustration, anger, increased appetite, insomnia, constipation, and diarrhea.
  • Toxicity in pregnant people and fetuses: Nicotine use is harmful for pregnant people and developing fetuses.
  • Additional side effects: Other possible side effects of nicotine use include: decreased appetite, increased heart rate, increased blood pressure, alertness, nausea, diarrhea.



According to the CDC, nicotine is present in 99% of e-cigarettes in the US.

Nicotine is highly addictive.

Use among teenagers

In 2019, the Food and Drug Administration (FDA) issued a warning letter to the manufacturer of JUUL for marketing and advertising to young adults and teenagers without demonstrating scientific evidence that the product does not pose less risk or is less harmful.

There is conclusive evidence that most e-cigarettes contain and emit potentially toxic substances, and that nicotine exposure via JUUL and other e-cigarettes harm adolescent brain development

Lung injury

In August and September of 2019, there were a substantial number of emergency department (ED) visits of patients suffering lung injury associated with e-cigarette and vaping products.

Sixty-eight associated deaths have been confirmed as of February 18, 2020.

Though the rates of these injuries and deaths declined after September 2019, experts are still monitoring trends to determine what exactly caused these injuries.

Laboratory data shows that vitamin E acetate found in some THC-containing e-cigarettes may be linked to this outbreak of lung injuries.

High nicotine

Data shows that ingesting, inhaling, or otherwise consuming high doses of nicotine can result in a dangerous or fatal overdose.

In human adults, a fatal dose of nicotine is estimated to be 50-60 mg.

Ultrafine particles

Ultrafine particles have been found in e-cigarette aerosol containers.

These particles can land deep in the user’s lungs after inhalation, posing additional potential risks.

Unknown long-term effects

Researchers are still working to identify additional long-term effects of e-cigarette use.

Until then, users of e-cigarettes can assume that there may be unknown long-term effects to their health.


More research is needed to determine whether or not e-cigarette use can cause seizures. 

Is JUUL Safer Than Smoking?

Research suggests that vaping and JUUL are less harmful than smoking.

Specifically, adults who smoke e-cigarettes are exposed to lower levels of major carcinogens as opposed to adults who smoke traditional cigarettes.

E-cigarettes may be more effective at helping adults quit smoking than other forms of nicotine-replacement therapy when accompanied by behavioral support, according to one randomized trial.

That doesn’t mean that vaping and JUUL are safe.

E-cigarettes still pose many risks to human health, especially for young adults and teens.

Are There Other Options?

Quitting smoking, vaping, and other forms of nicotine use can be difficult, but there are effective options:

  • Medications: Some forms of nicotine replacement therapy may require a prescription, but others don’t.
  • Behavioral therapy: Finding support with an individual or great therapist can help you to quit smoking or vaping.

Considering quitting vaping? Chat with a medical professional today to discuss your options.

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When to See a Doctor

If you’re having trouble quitting smoking or e-cigarette use, reach out to your doctor for help.

They can recommend effective and flexible treatment options to support you.

If you’re experiencing any new or bothersome side effects since starting e-cigarettes or JUUL, talk to a healthcare provider as soon as possible.

How K Health Can Help

Did you know you can get affordable primary care with the K Health app? Download K Health to check your symptoms, explore conditions and treatments, and if needed text with a provider in minutes. K Health’s AI-powered app is based on 20 years of clinical data.

Frequently Asked Questions

What are the dangers of JUULing?
Risks include addiction, impaired brain development in youth and young adults, lung injury, overdose, ultrafine particle exposure, and cardiovascular disease.
Does JUULing cause cancer?
Researchers are still learning about whether or not JUUL and other e-cigarettes can cause cancer. However, the American Cancer Society warns that the aerosol produced by JUUL and other e-cigarettes can contain cancer-causing chemicals.
K Health articles are all written and reviewed by MDs, PhDs, NPs, or PharmDs and are for informational purposes only. This information does not constitute and should not be relied on for professional medical advice. Always talk to your doctor about the risks and benefits of any treatment.

K Health has strict sourcing guidelines and relies on peer-reviewed studies, academic research institutions, and medical associations. We avoid using tertiary references.

Andrew Yocum, MD

Dr Andrew Yocum is a board certified emergency physician. He graduated Summa Cum Laude from Kent State University with a Bachelor of Science in Molecular Biology before attending Northeast Ohio Medical University where he would earn his Medical Doctorate (MD).