Does Vaping Cause Bad Breath? What Three Studies Found — and What None of Them Measured
Last updated: 29 October 2026
Quick Answer
Possibly — but the evidence is thinner than most pages admit. The largest study so far, a 2025 survey of 7,973 adults aged 18–40, found that people who used only vapes had about 1.6 times the odds of self-reported bad breath compared with non-users (adjusted odds ratio 1.576). A small 2022 pilot funded by a tobacco company found that vape breath smelled much less of smoke than cigarette breath, and was comparable to non-smokers’ breath, right after use. Neither study measured the sulfur gases that actually cause bad breath. A 2023 review concluded there is “still little evidence” on the effects of vaping on oral health.
The likely routes, in order of how well they are supported, are a drier mouth, sweet or flavoured residue that bacteria can cling to, and gum problems that nicotine can hide. A simple 7-day log (below) helps you tell which one is yours. If gum-line freshness is the part you want to support, a water-free botanical lipid concentrate such as Dental Pro 7 is one example — it supports the look and feel of a fresher mouth, but it will not replace lost saliva or stand in for a dental check-up.
Why the usual answer is unsatisfying
Search this question and most pages say the same thing: vape liquid contains propylene glycol and glycerin, these dry your mouth, a dry mouth smells. It sounds neat, and parts of it may be true. But very few of those pages cite a study that measured the breath of a single vaper. That is not an accident — as we found when reading the research, almost nobody has done it.
Two points need stating plainly. First, this article is not a verdict on whether vaping is safer or riskier than smoking; it only asks what the research shows about breath. Second, every study below is observational, so none of them can prove that vaping causes bad breath — only whether the two travel together.
What the three key studies actually found
1. The big survey: higher odds of bad breath in vapers
Saleh and colleagues, publishing in Scientific Reports in 2025, surveyed 7,973 adults aged 18–40 across 18 Middle Eastern and North African countries (data collected November 2023 to May 2024). Of these, 5,668 were non-users, 1,003 used only electronic nicotine delivery systems (vapes), 859 used only traditional tobacco, and 443 used both. Bad breath was scored with a 15-question tool called the Halitosis Finding Score; a score of 14 or more counted as halitosis.
After adjusting for age, sex, dental problems, regular oral hygiene, daily water intake and alcohol, vape-only users had higher odds of halitosis than non-users (adjusted odds ratio 1.576, 95% CI 1.367–1.817), and dual users did too (1.420, 95% CI 1.161–1.738). Surprisingly, the authors report no significant association for exclusive traditional tobacco use. The catch: everything was self-reported through an online form recruited by convenience sampling, and the authors themselves say the design “restricts our ability to determine causal relationships.”
2. The small pilot: vape breath smells less of smoke — right after puffing
Dalrymple and colleagues (Scientific Reports, 2022) compared 11 cigarette smokers, 11 e-cigarette users and 11 non-smokers. After eight puffs, eight trained judges, blind to group, smelled each person’s breath. Cigarette smokers’ breath had significantly higher smoke intensity and lower pleasantness than both other groups (p < 0.0001 for smoke intensity; p ≤ 0.001 for pleasantness), while e-cigarette users and non-smokers did not differ significantly.
Read it with care: the study was funded by British American Tobacco and all authors are employed by it or by the contract research firm; it had only 11 people per group; breath was assessed at a single time point; and it measured smoke odour and pleasantness, not halitosis or sulfur compounds. The authors note that the long-term effect of e-cigarette use on breath odour is “still unknown.” It tells us that a vape does not leave a cigarette smell on the breath; it does not tell us that vapers have fresh breath all day.
3. The review: nobody has measured it directly
Zhang and Wen’s 2023 review in Frontiers in Public Health compared the oral-disease risk of vapes and cigarettes. As reported by the review, none of the studies it cited measured halitosis directly; the idea that vapes do not cause bad breath appears as something vapes are claimed to do, and former smokers reported improvements in taste and bad breath after switching. Its closing line: “there is still little evidence on the short- or long-term effects of ENDS on oral health.”
| Study | Who / how big | What was measured | What it found | The limit |
|---|---|---|---|---|
| Saleh et al., 2025 | 7,973 adults, 18–40 | Self-reported halitosis score (Halfins) | Vape-only: odds ratio 1.58; dual users: 1.42; tobacco-only: not significant | Self-report, convenience sample, cannot show cause |
| Dalrymple et al., 2022 | 33 adults (11 per group) | Judges’ ratings of smoke odour and pleasantness after 8 puffs | Vape breath comparable to non-smokers; cigarette breath worse | Tobacco-company funded; one time point; not halitosis |
| Zhang & Wen, 2023 (review) | Literature review | Oral-health evidence on vapes | No halitosis study cited; “little evidence” overall | A review, not new data |
Gap shared by all three: none measured hydrogen sulfide, methyl mercaptan or dimethyl sulfide — the compounds that, per a halitosis review by Izidoro and colleagues, make up 90% of the volatile sulfur compounds in bad breath.
The 3 ways a vape could change your breath
With no direct measurements, the honest approach is to list the plausible routes and note how well each is supported.
Route 1: A drier mouth — plausible, but mixed evidence
Dry mouth matters because saliva is the mouth’s cleaner. The NIDCR says saliva “washes away food particles from the teeth and gums,” lists bad breath as a symptom of dry mouth, and notes that dry mouth “increases the risk for tooth decay or fungal infections.” Mayo Clinic says dry mouth naturally occurs during sleep, which is why morning breath exists. For smoking, a 2010 case-control study of 200 dental patients in Iran found resting salivary flow of 0.38 ml/min in smokers versus 0.56 ml/min in non-smokers.
For vapes the data are weaker. Zhang and Wen state that propanediol (propylene glycol) “combines readily with saliva, resulting in dry mouth,” but cite no study for that. The one human figure they report cuts the other way: in a Northern California adolescent cohort, frequent vape users reported dry mouth at 14%, the same as non-smokers, versus 19% for tobacco and cannabis users. So dryness is a reasonable suspect, not a proven one.
Route 2: Sweet, flavoured residue that bacteria can cling to — lab evidence only
The same review reports lab work suggesting that glycerin combined with flavouring “may be associated with a four-fold increase in microbial adhesion” (Fairchild & Setarehnejad, Br Dent J 2021), and that vape exposure increased S. mutans growth and adherence in the lab. Those are bacteria linked to cavities rather than to breath, and lab results are not people. Treat this as a hypothesis: sugary-feeling film in a dry mouth is the kind of environment where odour-producing bacteria do well — but nobody has shown that in vapers.
Route 3: Gum trouble that nicotine hides — the one worth checking
This is the route most pages miss. Gum disease and tongue coating are the leading causes of bad breath in the Izidoro review, which puts most halitosis down to “inadequate oral hygiene, periodontitis and tongue coating.” And nicotine can make gum trouble harder to spot. The American Academy of Periodontology says “the nicotine and other chemicals found in tobacco products can hide the symptoms commonly associated with periodontal disease, such as bleeding gums.”
A 2019 Saudi study of 46 cigarette smokers, 44 e-cigarette users and 45 never-smokers in Archives of Oral Biology (BinShabaib et al.) fits the pattern: per its abstract, bleeding on probing was more common in never-smokers than in either smoking group, even though smokers had higher probing depth and attachment loss than never-smokers. In plain terms, a vaper with no bleeding is not necessarily a vaper with healthy gums. If bad breath is your only sign, a dental check is the sensible first step. (We could read only the abstract of this paper; it reports no e-cigarette-versus-never-smoker comparison for depth or attachment loss.)
The 7-day vape-breath log (our protocol)
The studies cannot tell you which route applies to you, but a week of notes can narrow it down. This is a self-observation tool devised for this article, not a validated test.
- Three scores a day. Rate your breath 0–5 on waking, about 10 minutes after a vaping session, and in the evening. Self-assessment is unreliable — Mayo Clinic suggests asking a close friend or relative — so get a second opinion at least twice. (See why you can’t smell your own bad breath.)
- Two yes/no notes. Was your mouth dry or sticky on waking? Did you notice a sweet or sticky film or taste after sessions?
- Two habits to hold steady. Drink water as usual and keep your normal brushing, so you are testing the vape, not a routine change.
| Pattern | What it points to | First move |
|---|---|---|
| Worst on waking, dry mouth, eases with water | Dryness (route 1) | Water through the day; sugarless gum to stimulate saliva (NIDCR) |
| Worse soon after sessions, fades within the hour | Residue and flavour (route 2) — our reading, unproven | Sip water after sessions; clean the tongue |
| Steady all day, bad taste, whatever you do | Gums, tongue or teeth (route 3) | Dental check — and tell the dentist you vape |
Cleveland Clinic gives a useful rule of thumb: “If you have a bad taste in your mouth, you’ve probably got bad breath that others can smell.” Its prevention list includes cleaning the tongue with a scraper, rinsing with an alcohol-free mouthwash, drinking plenty of water, and avoiding alcohol, caffeine and tobacco products that can dry the mouth. For the tongue step, see our guide to tongue scrapers.
What helps, and what only masks
- Water and saliva first. It is the cheapest, best-supported step. More in why your mouth is always dry.
- Do not rely on mints, gum or mouthwash alone. Mayo Clinic calls these “only short-term measures” that “don’t address the cause of the problem.”
- Brush and floss to the gum line, and see why breath can still smell after brushing and flossing.
- Book a check-up if it lasts. If you have also quit or cut down on cigarettes, our post on breath after quitting smoking and the unmasking effect on gums explain why things can look worse before they look better. The wider picture is in the bad breath causes guide.
Where Dental Pro 7 fits — and where it doesn’t
If vaping is part of your picture, the part you can control is the gum line, where bacteria collect and where nicotine can hide early warning signs. A product cannot replace saliva or tell you whether your gums need a dentist — but it can support the look and feel of a fresher mouth alongside the basics above.
Dental Pro 7 is a 100% water-free botanical lipid concentrate formulated by S. C. Aris. Because it is anhydrous, it is built to stay in contact with the gum line instead of washing away like a water-based paste. It contains no water, fillers, SLS or foaming agents, preservatives or parabens, or fluoride. Its freshness trinity is peppermint, spearmint and wild mint, alongside botanicals including immortelle helichrysum, pomegranate seed, black cumin seed, Indian myrrh, wild clove, white thyme and eucalyptus. It supports the look of healthier-looking, pinker gums and a fresher-feeling mouth.
How to use it: put 4 drops on a dry toothbrush in place of toothpaste, brush gently for about 2 minutes, then spit — do not rinse with water. A rinse option, DP7 Pro Rinse, is also available.
Customer rating: 4.9 out of 5 from 293 reviews, backed by a 90-day guarantee.
A note for sensitive mouths: Dental Pro 7 is built on aromatic botanicals and naturally contains eugenol, limonene and linalool. If you react to fragrances or plant extracts, check the ingredient list first and speak to your doctor or dentist before using it.
This article is for general information and is not medical advice. Dental Pro 7 is a cosmetic oral-care product and is not intended to diagnose, treat or manage dry mouth, gum disease, nicotine dependence or any medical condition. See a dentist or doctor if your breath problem persists.
Frequently asked questions
Does vaping cause bad breath?
It is associated with it in one large survey (about 1.6 times the odds of self-reported bad breath in vape-only users), but no study has measured the sulfur gases that cause bad breath in vapers, and the survey cannot prove cause.
Does vape breath smell like cigarette breath?
Not right after use, according to a small tobacco-company-funded pilot of 33 adults: vape breath was rated comparable to non-smokers’ breath and much less smoky than cigarette breath. That study did not look at how breath smells hours later or over months.
Does vaping cause dry mouth?
It is often claimed, but the evidence is mixed. A review attributes it to propylene glycol without citing a study, while one cohort it cites found dry mouth in 14% of frequent vape users, the same as non-smokers.
Can vaping hide gum disease?
Nicotine can hide signs such as bleeding gums, according to the American Academy of Periodontology, and a 2019 study found less bleeding on probing in smokers and e-cigarette users than in never-smokers. Tell your dentist you vape and keep up regular check-ups.
How do I tell whether my bad breath is from vaping or my gums?
Keep the 7-day log above. Breath that is worst on waking and eases with water points to dryness; breath that stays bad all day with a persistent taste points to gums, tongue or teeth and deserves a dental check.
Sources
- Saleh SM, Shata A, Tiryag AM, et al.; DARS Consortium. “Halitosis among users of electronic nicotine delivery systems in a multi-center cross-sectional study.” Sci Rep 2025;15:20287. doi.org
- Dalrymple A, Coburn S, Brandt M, Hardie G, Murphy J. “Pilot study to determine differences in breath odour between cigarette and e-cigarette consumers.” Sci Rep 2022;12:2204. springer.com
- Zhang Q, Wen C. “The risk profile of electronic nicotine delivery systems, compared to traditional cigarettes, on oral disease: a review.” Front Public Health 2023;11:1146949. frontiersin.org
- BinShabaib M, ALHarthi SS, Akram Z, et al. “Clinical periodontal status and gingival crevicular fluid cytokine profile among cigarette-smokers, electronic-cigarette users and never-smokers.” Arch Oral Biol 2019;102:212–217. pubmed.ncbi.nlm.nih.gov
- Rad M, Kakoie S, Niliye Brojeni F, Pourdamghan N. “Effect of long-term smoking on whole-mouth salivary flow rate and oral health.” J Dent Res Dent Clin Dent Prospects 2010;4(4):110–114. pmc.ncbi.nlm.nih.gov
- Izidoro C, Botelho J, Machado V, et al. “Revisiting standard and novel therapeutic approaches in halitosis: a review.” Int J Environ Res Public Health 2022;19(18):11303. mdpi.com
- American Academy of Periodontology. “Gum health and tobacco use.” perio.org
- NIDCR. “Dry mouth.” nidcr.nih.gov
- Mayo Clinic. “Bad breath — symptoms and causes.” mayoclinic.org
- Cleveland Clinic. “Bad breath (halitosis).” my.clevelandclinic.org