Vaping is linked to some inflammation, though less than smoking. A 2025 meta-analysis of 16 studies found people who vape had higher levels of two inflammation signals than non-smokers, and lower levels than smokers. Most of this research is a snapshot in time, so it can't yet prove that vaping is the cause.
What inflammation looks like in your blood
Inflammation is your body's alarm system. A short burst helps you heal. A low alarm that stays on for years is the kind researchers worry about. CRP (C-reactive protein) is a blood protein that rises with inflammation, and IL-6 and TNF-alpha are signals immune cells use to call for backup. Smoking is a well-known cause of lung disease, and inflammation is part of how it does that damage. In a study of 1,819 adults aged 55 to 74, current smokers were more likely than never smokers to have high CRP, and current smoking was tied to 10 different inflammation markers.
So the question for vaping is simple. Does it set off the same alarm?
Does vaping cause inflammation?
Vaping does seem to stir up some inflammation, just less of it. A 2025 meta-analysis (a study that pools many studies) gathered 16 studies with 24,079 adults. People who vaped had higher IL-6 and TNF-alpha than non-smokers, but lower levels than smokers. The authors call for long-term studies to show cause and effect.
People who vape had more inflammation signals than non-smokers, and fewer than smokers.From a 2025 meta-analysis in Int J Public Health
The lungs tell a similar story. In one study, doctors looked inside the lungs of 73 people with a thin camera and washed out a sample of cells. People who vaped landed in between smokers and never-smokers, and for most markers they looked more like the never-smokers. The authors also warned that vaping may have effects of its own that their tests did not measure.
Your gums count too. A 2023 review of 16 studies found that smokers had more inflammation chemicals in their gums than people who vaped or didn't smoke. Vaping still showed harmful effects on gum health.
Is vaping less inflammatory than smoking?
On blood tests, mostly yes. A 2025 study pooled 18,797 people from 6 long-running research cohorts, and 5,806 of them had their CRP measured. People who only vaped had lower CRP than people who only smoked, and their CRP was not clearly different from people who never smoked.
A large US survey, the PATH Study, measured CRP, IL-6 and three other markers in 3,712 adults. Former smokers who now only vaped had levels similar to former smokers who used nothing, and lower than current smokers.
"Less than smoking" is not the same as "harmless." A 2021 review pooled 15 studies on asthma and 9 on COPD, a long-term lung disease. Vaping was linked to 39% higher odds of asthma and 49% higher odds of COPD, even after the researchers accounted for cigarette smoking. Lab studies show vapor can trigger inflammation, though much less than smoke.
Devices also keep changing. A 2022 study compared users of older vape pens with users of newer pods and disposables, about 20 to 30 people per group. The newer-device users had more cells shed from the airway lining in their mucus, a sign of airway injury, and lower levels of several immune signals. The authors called the effects of newer devices unique, and different from older ones.
What about vaping and smoking at the same time?
This is the group that often does worst. In the 2025 study of 6 cohorts, people who both vaped and smoked had CRP levels close to people who only smoked. In the PATH Study, people who did both had more of a marker of oxidative stress (cell wear from unstable oxygen molecules) than people who only smoked.
Cutting down on cigarettes while adding a vape doesn't seem to calm the alarm much.
Does quitting calm inflammation down?
Here the evidence comes mostly from quitting cigarettes. Among older smokers, several markers, CRP among them, showed trends across the years since people quit. The authors wrote that quitting may let marker levels drift back toward those of never smokers over time.
Switching fully to vaping showed some of the same shift. In a randomized trial, 450 long-term smokers either kept smoking or switched to a vape. Among the 150 people followed for 24 weeks, the switchers had lower white blood cell counts and lower levels of a blood vessel stress marker (sICAM). The authors said these changes came close to what has been reported for quitting smoking.
What about quitting vaping itself? We could not find a study that tracked inflammation markers after people stopped vaping.
What this means for you
Tick what you'll try this week. Your picks stay on this device.
you have asthma, COPD or another lung condition; you get a cough, wheezing or shortness of breath that won't go away; you want help to quit and are thinking about quit-smoking medicines; or you have tried to quit before and gone back.
One tap. Results appear once 50 readers have voted, and the count is always real.
The bottom line
Picture three people at a blood draw: one smokes, one vapes, one has never done either. The person who vapes usually lands in the middle, and closer to the non-smoker than to the smoker. That middle spot is real progress for someone coming off cigarettes. It is still not zero, and nobody has followed vapers long enough to know what the middle spot costs over decades. The cleanest number on any of these tests belongs to the person breathing nothing but air.
Common questions
Is vaping bad for inflammation?
It is linked to some. Across 16 studies, people who vaped had higher IL-6 and TNF-alpha than non-smokers, but lower than smokers. In a study that looked inside people's lungs, vapers sat between smokers and never-smokers, closer to never-smokers on most markers. Vaping is also linked to higher odds of asthma and COPD.
Does vaping nicotine cause inflammation?
People who vaped had higher IL-6 and TNF-alpha than non-smokers. But it's hard to blame nicotine alone. Lab studies point to vapor in general, and the device, the liquid and the flavors may all change how much harm it does. One study found newer pods and disposables affected the airways differently from older vape pens.
Does quitting vaping reduce inflammation?
No study we found tracked inflammation after people quit vaping. The closest clue comes from smokers: inflammation markers in former smokers trend back toward never-smoker levels over time. And in a large US survey, an oxidative stress marker was lower the longer people had been off cigarettes, whether or not they now vaped.
Ask the Research Desk
Heard something about inflammation you want checked? The best questions become articles, credited by first name only if you say yes.
How this article was made
Researched and written from 10 peer-reviewed papers. Our automated check matched every claim against the exact words of its source, confirmed every paper exists in PubMed, and found none retracted. Checked October 31, 2026. Not individually reviewed by a doctor. Photos are illustrative; the people in them are not patients or readers.
Grades run Strong, Moderate, Emerging, Early and Not supported, and the grade decides the words we may use. How we grade evidence · Medical disclaimer
Sources
- Meta-analysisInflammatory and Carcinogenic Biomarker Signatures in E-Cigarette Users: A Comprehensive Meta-Analysis of ∼24,000 Adults.Bin Abdulrahman KA, Bin Abdulrahman AK, Anwer R Int J Public Health, 2025.PubMedFull paper
- CohortUse of e-cigarettes, traditional combustible cigarettes, and high sensitivity C-reactive protein: The Cross Cohort Collaboration.Yao Z, Tasdighi E, Dardari ZA et al. Am Heart J, 2025.PubMedFull paper
- Cross-sectionalBiomarkers of Inflammation and Oxidative Stress among Adult Former Smoker, Current E-Cigarette Users-Results from Wave 1 PATH Study.Christensen CH, Chang JT, Rostron BL et al. Cancer Epidemiol Biomarkers Prev, 2021.PubMedFull paper
- Randomized trialBiomarkers of Exposure and Biomarkers of Potential Harm in Adult Smokers Who Switch to e-Vapor Products Relative to Cigarette Smoking in a 24-week, Randomized, Clinical Trial.Edmiston JS, Webb KM, Wang J et al. Nicotine Tob Res, 2022.PubMedFull paper
- Cross-sectionalBiomarkers of Exposure and Effect in the Lungs of Smokers, Nonsmokers, and Electronic Cigarette Users.Song MA, Freudenheim JL, Brasky TM et al. Cancer Epidemiol Biomarkers Prev, 2020.PubMedFull paper
- Cross-sectionalBiomarkers of Airway Immune Homeostasis Differ Significantly with Generation of E-Cigarettes.Hickman E, Payton A, Duffney P et al. Am J Respir Crit Care Med, 2022.PubMedFull paper
- Meta-analysisE-cigarette use and respiratory disorders: an integrative review of converging evidence from epidemiological and laboratory studies.Wills TA, Soneji SS, Choi K et al. Eur Respir J, 2021.PubMedFull paper
- Meta-analysisThe impact of electronic and conventional cigarettes on periodontal health-a systematic review and meta-analysis.Thiem DGE, Donkiewicz P, Rejaey R et al. Clin Oral Investig, 2023.PubMedFull paper
- ReviewA Review of Pulmonary Toxicity of Electronic Cigarettes in the Context of Smoking: A Focus on Inflammation.Shields PG, Berman M, Brasky TM et al. Cancer Epidemiol Biomarkers Prev, 2017.PubMedFull paper
- ObservationalCigarette smoking and variations in systemic immune and inflammation markers.Shiels MS, Katki HA, Freedman ND et al. J Natl Cancer Inst, 2014.PubMedFull paper
