Xylitol
Xylitol (a five-carbon sugar alcohol, also called a polyol)
TL;DR
A sugar alcohol sweetener tested for preventing tooth decay. Results are mixed: gum helped some high-risk children, but a large adult trial found no significant benefit. Large doses cause diarrhea, and xylitol is toxic to dogs.
Ideal For
- Children at moderate or high caries risk who can use xylitol gum after meals
- People replacing added sugar with a non-cariogenic sweetener
Avoid If
- You have dogs at home and cannot keep products out of reach
- Large amounts upset your bowel
- You have heart disease and want to use large daily amounts without asking your clinician
Frequently Asked Questions
Does xylitol prevent cavities?
How much xylitol should I use a day?
Can xylitol cause diarrhea?
Is xylitol safe for the heart?
Is xylitol dangerous for dogs?
Does xylitol prevent ear infections or sinus problems?
Overview
Xylitol, also known as birch sugar or wood sugar, is a five-carbon sugar alcohol. It is slightly lower in calories than sugar and is used to sweeten sugar-free gum, mints, candy, toothpaste and mouthwash. The FDA also lists chewable vitamins, cough syrup, some nut butters and dietary supplements among the products that may contain it. Oral bacteria do not readily turn it into acid, so dental groups regard it as a non-cariogenic sugar substitute.
Its main research use is preventing tooth decay (dental caries), and the evidence is mixed. A 2015 Cochrane review of 10 trials found low-quality evidence that a fluoride toothpaste containing 10% xylitol may reduce caries by 13% in children, and the remaining evidence was too weak to judge. Trials of xylitol gum in children at moderate or high caries risk look more favourable, but the largest adult trial of xylitol lozenges (691 people, 33 months) was not significantly different from placebo. The American Academy of Pediatric Dentistry says the evidence is insufficient to show xylitol prevents caries on its own, and that its real value lies as a sugar substitute.
Safety is mostly a matter of dose. Large amounts draw water into the bowel and cause gas, cramps and diarrhea, and xylitol is poisonous to dogs. A 2024 study linked higher blood xylitol to cardiovascular events in people with heart-disease risk, a signal that needs confirming, and a small 2026 preprint found no acute rise in platelet aggregation. Trials of ear infections and sinus symptoms are few, small or mostly from one research group, and the evidence there is thin.
How It Works
- Oral bacteria do not readily metabolize xylitol, so it does not feed acid production in plaque the way sugar does.
- It is hypothesized to lower mutans streptococci (the main decay-causing bacteria) and lactic acid production in plaque and saliva, with minimal effect on normal flora.
- Chewing gum stimulates saliva, which may add to the benefit and makes gum trials hard to separate from the effect of xylitol itself.
- Xylitol is poorly absorbed from the small intestine, which is why large doses cause osmotic diarrhea; regular use can lead to adaptation.
- In people, xylitol does not stimulate insulin release, unlike in dogs, where it can cause a dangerous drop in blood sugar.
- In laboratory work it can reduce the adherence of Streptococcus pneumoniae and Haemophilus influenzae to nasal cells, the reasoning behind ear-infection trials.
Quick Facts
- Cochrane 2015: 13% less caries with 10% xylitol fluoride toothpaste
- Adult lozenge trial of 691 people: no significant benefit
- AAPD: 5-10 g daily, three to five times after meals
- Diarrhea with single doses of 35 g or more
- FDA: toxic to dogs; low blood sugar in 10-60 minutes, sometimes delayed 12-24 hours
Benefits & Outcomes
No linked outcomes yet. Research is ongoing.
Health Concerns Addressed
Acute Otitis Media
Xylitol may lower ear infection rates in healthy day care children in older trials, but later trials conflict and guidelines do not recommend it.
Dental Caries
Xylitol gum may help children at moderate or high caries risk, but the evidence overall is low quality and does not show it prevents cavities on its own.
Supporting Research24 studies
Xylitol syrup for the prevention of acute otitis media
Vernacchio L, Corwin MJ, Vezina RM +4 more
was ineffective in reducing clinically diagnosed AOM among otitis-prone children
Results from the Xylitol for Adult Caries Trial (X-ACT)
Bader JD, Vollmer WM, Shugars DA +4 more
did not result in a statistically or clinically significant reduction in 33-month caries increment
A novel use of xylitol sugar in preventing acute otitis media
Uhari M, Kontiokari T, Niemelä M
effective in preventing AOM and decreasing the need for antimicrobials
Xylitol chewing gum in prevention of acute otitis media: double blind randomised trial
Uhari M, Kontiokari T, Koskela M +1 more
Xylitol seems to have a preventive effect against acute otitis media
Xylitol-containing products for preventing dental caries in children and adults
Riley P, Moore D, Ahmed F +2 more
a fluoride toothpaste containing 10% xylitol may reduce caries by 13%
The effect of xylitol chewing gums and candies on caries occurrence in children: a systematic review with special reference to caries level at study baseline
Pienihäkkinen K, Hietala-Lenkkeri A, Arpalahti I +1 more
well demonstrated in children and adolescents with high or moderate caries level at study baseline
Threshold for transitory diarrhea induced by ingestion of xylitol and lactitol in young male and female adults
Oku T, Nakamura S
non-effective dose level of xylitol was 0.37 g/kg B.W. for males
Xylitol pediatric topical oral syrup to prevent dental caries: a double-blind randomized clinical trial of efficacy
Milgrom P, Ly KA, Tut OK +4 more
effective in preventing early childhood caries
A Systematic Review and Meta-Analysis of the Role of Sugar-Free Chewing Gum in Dental Caries
Newton JT, Awojobi O, Nasseripour M +4 more
the PF was 33% (95% CI, 4% to 61%)
The effectiveness of xylitol in a school-based cluster-randomized clinical trial
Lee W, Spiekerman C, Heima M +4 more
Xylitol consumption did not have additional benefit beyond other preventive measures
The caries preventive effect of 1-year use of low-dose xylitol chewing gum. A randomized placebo-controlled clinical trial in high-caries-risk adults
Cocco F, Carta G, Cagetti MG +3 more
showed a significantly lower increment of initial and extensive caries lesions
Gastrointestinal tolerance of erythritol and xylitol ingested in a liquid
Storey D, Lee A, Bornet F +1 more
35 and 50 g xylitol was associated with significant intestinal symptom scores and watery faeces
Xylitol for preventing acute otitis media in children up to 12 years of age
Azarpazhooh A, Lawrence HP, Shah PS
xylitol (in any form) can reduce the risk of AOM from 30% to around 22%
Xylitol administered only during respiratory infections failed to prevent acute otitis media
Tapiainen T, Luotonen L, Kontiokari T +2 more
Xylitol administered only during an ARI was ineffective in preventing AOM
Failure of xylitol given three times a day for preventing acute otitis media
Hautalahti O, Renko M, Tapiainen T +3 more
failed to prevent AOM
Tolerability of oral xylitol solution in young children: implications for otitis media prophylaxis
Vernacchio L, Vezina RM, Mitchell AA
Oral xylitol solution at dosages of 5g TID and 7.5g QD is well-tolerated by young children
Xylitol for the prevention of acute otitis media episodes in children aged 1-5 years: a randomised controlled trial
Persaud N, Azarpazhooh A, Keown-Stoneman C +4 more
Regular use of xylitol did not prevent AOM, URTIs or dental caries
Cluster-randomized xylitol toothpaste trial for early childhood caries prevention
Chi DL, Tut O, Milgrom P
no more efficacious in reducing ECC than a fluoride-only toothpaste
Effect of maternal use of chewing gums containing xylitol on transmission of mutans streptococci in children: a meta-analysis of randomized controlled trials
Lin HK, Fang CE, Huang MS +4 more
significantly reduced in the xylitol group
Xylitol is prothrombotic and associated with cardiovascular risk
Witkowski M, Nemet I, Li XS +4 more
Xylitol is associated with incident MACE risk
Milk Sweetened with Xylitol: A Proof-of-Principle Caries Prevention Randomized Clinical Trial
Chi DL, Zegarra G, Vasquez Huerta EC +4 more
differences in caries incidence were not detected
Xylitol nasal irrigation in the management of chronic rhinosinusitis: a pilot study
Weissman JD, Fernandez F, Hwang PH
xylitol irrigations result in greater improvement of symptoms of chronic rhinosinusitis as compared to saline irrigation
Effect of non-fluoride agents on the prevention of dental caries in primary dentition: A systematic review
Wang Y, Li J, Sun W +3 more
daily use of xylitol wipes is a useful adjunct for caries control in young children
Xylitol nasal spray for prevention of recurrent acute otitis media in children: A prospective two-center cohort study
Margulis I, Cohen-Kerem R, Stein N +4 more
The findings support the effectiveness and safety of nasal xylitol spray
Safety Information
Potential Side Effects
Gas, bloating, cramps, loose stools and diarrhea, mainly with large or sudden doses. In a 6-month trial in children aged 1-5, diarrhea was reported by 34% on xylitol syrup and 28% on the sorbitol comparison. The Cochrane caries review lists mouth sores, cramps, bloating, constipation, flatulence and loose stool among reported effects.
Contraindications
Keep every xylitol product away from dogs. People with heart disease should ask their clinician before using large amounts, given a 2024 cardiovascular signal.
Drug Interactions
- No specific drug interactions were reported in the trials and policy statements reviewed for this page; tell your pharmacist if you use xylitol products regularly alongside several medicines.
Pregnancy & Breastfeeding
Pregnancy: Not enough evidence to judge
Breastfeeding: Not enough evidence to judge
Dosage Guidelines
Dosage Used in Studies
5-10 g
Best Time to Take
After meals and snacks, spread over 3-5 exposures a day
Best Form
Gum is the best-studied form for caries, and trials favour it in children at moderate or high caries risk
Bioavailability
Poorly absorbed from the small intestine, so a large single dose draws water into the bowel.
Dosing by Goal
| Goal | Dose | Notes |
|---|---|---|
| Dental caries prevention (AAPD policy) | 5-10 g a day of 100% xylitol | Taken three to five times a day after meals; the policy calls this possibly unrealistic and says under three exposures a day gave no protection in the data it reviewed. |
| Adults at high caries risk, gum | 2.5 g a day | Used for 1 year in a trial of 179 adults, with a 23% lower tooth-level risk than polyol gum at 2 years. |
| Infants, topical syrup | 8 g a day in 2 or 3 doses | Studied in children aged 9-15 months for about 10 months. Use only on a pediatric dentist's advice. |
| Upper limit before diarrhea (single dose) | About 0.37-0.42 g per kg body weight | The non-effective dose in healthy young adults; 35 g or more in water caused watery stools in a crossover study. |
Forms Compared
Chewing gum
Best for Children and adults at moderate or high caries risk
Best-studied form for caries. A 2024 systematic review found gum reduced caries in children at moderate or high caries risk; chewing also raises saliva flow.
Candies, mints and lozenges
Best for Those who cannot chew gum; benefit unproven
Mixed: in five of six heterogeneous candy studies in children no caries reduction was found, and the large adult lozenge trial was not significant.
Toothpaste (with fluoride)
Best for Children, in place of a fluoride-only paste
A fluoride toothpaste containing 10% xylitol was linked to 13% less caries than fluoride alone in a Cochrane analysis (low-quality evidence); a separate 6-month trial found no difference.
Topical syrup and wipes
Best for Infants, under a pediatric dentist's guidance
Used in infants and toddlers in small trials; one syrup trial at 8 g a day reduced decayed teeth, and wipes were called a useful adjunct in one small low-risk-of-bias study.
Bulk powder
Best for Replacing sugar in the diet
A sugar substitute for drinks and baking. Dose is easy to overshoot, and it is a hazard to pets.
Food & Timing
After eating, chewed or dissolved slowly in the mouth rather than swallowed in one large dose
Medical Disclaimer
The information provided on this website is for educational and informational purposes only and is not intended as a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition or before starting any supplement regimen.
Individual results may vary. The statements on this website have not been evaluated by the Food and Drug Administration. Products and information are not intended to diagnose, treat, cure, or prevent any disease.