Effects of Vaping on the Lungs
You have probably seen strong claims about vaping and your lungs from both directions: that vaping is as bad as smoking or worse, or that it has no effect at all. The honest answer is less dramatic and less certain. Research is ongoing, long-term studies are limited, and experts do not agree on every detail.
This article walks through the concerns you hear most often, what is and isn’t known, and where to find current guidance. It is general information, not medical advice.
Short version: Vaping heats e-liquid instead of burning tobacco, but the aerosol is not just water vapor, and its long-term effects on the lungs are still being studied. If you have questions about your lungs, talk to a doctor, and check cdc.gov and fda.gov for current guidance.
What you breathe in when you vape
A vape doesn’t burn anything. A battery heats a coil, and the coil turns e-liquid into an aerosol that you inhale. E-liquid is usually a mix of propylene glycol (PG), vegetable glycerin (VG), flavorings and, in most cases, nicotine. Our guide to what is in vape juice covers each ingredient.
Because nothing is burned, vaping doesn’t produce smoke. That doesn’t mean the aerosol is just water vapor, though. The CDC notes that e-cigarette aerosol can contain nicotine, ultrafine particles, flavoring chemicals such as diacetyl, volatile organic compounds and heavy metals such as nickel, tin and lead. How much of each is present depends on the product, the device and how it is used.
Popcorn lung and diacetyl
Popcorn lung is the common name for bronchiolitis obliterans, a serious lung disease that scars the smallest airways. It got its nickname after cases were found among workers at a microwave popcorn plant who had been exposed to diacetyl, a chemical widely used at the time to create a buttery flavor.
Diacetyl has been found in some e-liquids, particularly some sweet and buttery flavors, which is why the CDC lists it among the substances vape aerosol can contain. Many e-liquid makers say they leave it out of their recipes. Public-health bodies differ on how much of a risk diacetyl in vape products poses, and research continues.
If you want to avoid diacetyl, look for the ingredient information a manufacturer publishes, or ask the brand directly.
The 2019 lung injury outbreak
In 2019, the US saw an outbreak of serious lung injuries among people who had vaped, which the CDC named EVALI. The CDC found it strongly linked to vitamin E acetate, an additive used in some THC vaping products, and most patients reported using THC products, many from informal sources. The agency also said it could not rule out other chemicals in some cases.
The CDC’s advice included avoiding THC vaping products from informal sources and never adding anything to a vaping product that the manufacturer did not intend. Our article on vaping deaths and the 2019 flavor bans covers the outbreak in more detail.
What the research says so far
Studies on vaping and the lungs fall into a few broad groups: lab studies on cells, animal studies and studies of people who vape. Results have been mixed, and each type has limits.
- Lab and animal studies can show how cells and tissue react to vapor, but researchers and critics have questioned whether some test conditions, such as very high power settings or unusually heavy exposure, reflect how people actually vape.
- Studies of people are harder to run. Many people who vape also smoke or used to, which makes it hard to separate the effects, and vaping has not been common for long enough to study decades of use.
That is why headlines so often seem to contradict each other. Scientists are still learning about the long-term effects of vaping on lung health, and public-health bodies update their advice as new evidence comes in.
How does vaping compare with smoking?
Adults who smoke often ask this, so here is the careful version. Nicotine is addictive, whether it comes from a cigarette or a vape. No vaping product is FDA-approved as a quit-smoking aid. Public-health bodies disagree on the details of how vaping compares with smoking. If you smoke and are thinking about switching, talk to your doctor first. Our article on vaping vs. smoking covers what different agencies have said.
Practical steps, and when to see a doctor
- Buy from licensed, age-verified retailers, and avoid unregulated or informal products.
- Never add anything to your vape juice or modify a product in a way the manufacturer did not intend.
- Replace a burnt coil rather than vaping through a harsh, burnt taste. Our burnt taste guide explains why it happens.
- See a doctor if you have a cough that won’t go away, shortness of breath, wheezing or chest pain. Get emergency care for severe trouble breathing.
- Tell your doctor that you vape and what you use, so they can give you better advice.
For current, independent guidance, visit the CDC and the FDA.
Common questions
Is vape vapor just water vapor?
No. It is an aerosol made mostly from PG and VG, along with flavorings and usually nicotine, and the CDC notes that it can contain other substances too.
Does vape juice contain diacetyl?
Some e-liquids have been found to contain it, while many manufacturers say they leave it out. Check the brand’s published ingredient information if you want to avoid it.
What were the symptoms of EVALI?
The CDC listed cough, shortness of breath and chest pain, often along with nausea, vomiting, stomach pain or diarrhea, and fever, chills or weight loss. Anyone with symptoms like these after vaping should see a doctor.
WARNING: This product contains nicotine. Nicotine is an addictive chemical. For adults 21+ only.