Xanthan Gum — The Fermented Polysaccharide That Gives Products Their Texture
Xanthan gum appears in 29,465 products in our database. It is a thickener: a very large sugar polymer, produced by bacterial fermentation, that turns a watery mixture into a gel and helps keep oil and water from separating on the shelf. The CIR Expert Panel assessed it as safe as used in cosmetics, and EFSA concluded no numerical daily intake limit is needed for it as a food additive. Its very high molecular weight means intact xanthan gum is expected to have very low penetration through intact skin.
Data sources: EU CosIng (#80699), CIR Safety Assessment of Microbial Polysaccharide Gums (2016), EFSA re-evaluation of E 415, ECHA CLP Annex VI and the ECHA Classification & Labelling Inventory, and SkinSenseDiary internal evaluation. No SCCS opinion exists for this ingredient. Last updated: September 2026.
At a Glance
Also Known As
Xanthan; Corn sugar gum; E 415
CosIng Functions
Viscosity modifier, Emulsifier, Skin conditioning, Surfactant
Source
Fermentation by Xanthomonas campestris on glucose or corn syrup
Regulation
No EU restrictions — not listed in Annex II / III / V
What Is Xanthan Gum?
Xanthan gum is a microbially produced polysaccharide used mainly as a thickener and stabiliser in cosmetic formulations, where it creates smooth, gel-like textures and helps keep ingredients from separating. It is generally well tolerated at cosmetic-use concentrations. Allergic contact reactions have been reported, although their frequency is not established.
Xanthan gum is made by fermentation. Xanthomonas campestris is grown in pure culture on glucose or corn syrup and secretes the polysaccharide as it feeds; the result is purified, dried and milled into a powder. It is described as natural in the sense that it is biologically produced rather than assembled by synthesis, though the process is industrial fermentation rather than extraction from a plant.
Its usefulness comes from its size and its behaviour under shear. With a molecular weight between one and ten million, xanthan gum forms a loose network in water that holds a formula together at rest, and thins as it is spread. That is why a gel-cream feels thick in the jar and light on the skin, and it is also why the ingredient is not expected to penetrate: CIR notes that polysaccharides of this size have negligible bioavailability when applied topically. Most of what xanthan gum does happens in the bottle, not in your skin.
What Does Xanthan Gum Do?
🧴
Builds and Holds Texture
Xanthan gum thickens the water phase of a formula, which is what turns a thin liquid into a serum, gel or lotion. CIR records use at 0.001–6% in leave-on products.
⚖️
Keeps Formulas from Separating
By raising the viscosity of the water phase it slows the movement of oil droplets and suspended particles, which is how emulsions and mineral sunscreens stay uniform between shakes. CosIng registers emulsifier among its functions.
💧
Thins as You Spread It
Xanthan gum solutions are shear-thinning: viscous at rest, more fluid under the friction of application. This is a property of the polymer network rather than an effect on skin, and it is the reason gel textures feel substantial in the container and light once applied.
✨
Forms a Light Surface Film
As water evaporates the polymer leaves a thin film on the surface, which contributes to a smooth after-feel. CosIng registers skin conditioning as a function, though this is a modest secondary effect rather than the reason it is in the formula. We make no claim that this film measurably reduces water loss — we found no study quantifying that for xanthan gum.
Generally suitable for: Most skin types, at cosmetic-use concentrations. Xanthan gum carries no EU allergen labelling requirement and is not part of standard patch-test series. Allergic contact dermatitis has been reported in isolated cases; its frequency is unknown.
Is Xanthan Gum Safe?
1
/ 10
Ingredient Hazard Rating — Low (provisional)
Xanthan gum has a substantial safety evidence base. The CIR Expert Panel concluded in 2016 that microbial polysaccharide gums, xanthan gum among them, are safe in cosmetic formulations in the present practices of use and concentration. Separately, EFSA re-evaluated it as food additive E 415 and found no safety concern for the general population, concluding that no numerical acceptable daily intake was needed. Those are assessments of two different exposure routes — topical and oral — and should not be read as two independent confirmations of topical safety. On hazard classification: xanthan gum has no EU harmonised classification under CLP Annex VI. Supplier notifications to the ECHA Classification & Labelling Inventory are split, with most reporting it as not classified and a minority reporting H315 (skin irritation) and H319 (serious eye irritation). No EU cosmetic restriction applies. Its very high molecular weight means intact xanthan gum is expected to have very low penetration through intact skin. This score is marked provisional: it was hand-assigned rather than derived from hazard codes, and it was assigned while our hazard table held no rows for this ingredient. It is under review.
Our rating is based on
CIR — Cosmetic Ingredient Review
✓ Safe as Used
The 2016 assessment of microbial polysaccharide gums concluded they are safe in cosmetic formulations in the present practices of use and concentration. Reported concentration of use: 0.001–6% in leave-on products and 0.000001–6% in rinse-off products.
EU Cosmetics Regulation
✓ No Restrictions
Not listed in Annex II (prohibited substances), Annex III (restricted substances) or Annex V (authorised preservatives). CosIng ref #80699 registers viscosity modifier, emulsifier, skin conditioning and surfactant among its functions; CosIng is informative and carries no legal force of its own.
EFSA — food additive E 415
✓ No numerical ADI required
EFSA’s re-evaluation found no safety concern for the general population at reported use levels, and no genotoxicity or carcinogenicity concern. Xanthan gum is unlikely to be absorbed intact and is fermented by intestinal microbiota. This assessment covers dietary intake only; EFSA states it does not extend to other uses.
Allergen & Sensitivity
Reported, frequency unknown
No EU fragrance-allergen labelling requirement applies. Xanthan gum is not part of standard patch-test series and no published frequency estimate exists. A 2015 case report in Contact Dermatitis identified it as the culprit allergen in a patient investigated for a sunscreen reaction. Read this as reported-but-unquantified — the absence of a frequency estimate is not evidence that the frequency is low.
GHS Hazard Flags — EU Harmonised Classification (CLP Annex VI, Raw Material)
No harmonised entry
✓ Not listed in CLP Annex VI
Xanthan gum has no entry in the EU harmonised classification and labelling table. This is a checked finding against the Annex VI list, not an inference from missing data in our own database.
GHS Hazard Flags — Supplier-Notified Classification (Not EU Harmonised)
Notifications disagree
Majority: not classified
Company notifications to the ECHA Classification & Labelling Inventory do not agree on this substance. The majority report xanthan gum as not classified, and individual supplier safety data sheets frequently state “not classified as a hazardous substance or mixture”. Notified classifications are self-assigned by the companies placing a substance on the market and are neither reviewed nor harmonised by the EU, which is why they can conflict with one another.
H315 — Skin Irrit. 2
Causes skin irritation (minority notification)
Reported by a minority of notifiers. Not part of any EU harmonised entry. It describes handling of the raw material rather than exposure from a finished cosmetic product.
H319 — Eye Irrit. 2
Causes serious eye irritation (minority notification)
Reported by a minority of notifiers alongside H315. CIR reports that xanthan gum at 1% was not an ocular irritant in rabbit eyes. As with H315, this is a raw-material handling classification and not a determination about finished cosmetics.
Things to Know
Animal irritation data: CIR reports xanthan gum up to 1% was not irritating to rabbit skin, and 1% was not an ocular irritant in rabbit eyes. One study using 5% aqueous xanthan gum on shaved rabbit skin produced localised irritation, but the report notes the study lacked details and controls. In guinea pigs, xanthan gum at 0.1% was not a sensitiser.
Human data is thinner than the animal data: CIR’s report contains no human repeat-insult patch test specific to xanthan gum. Confidence in its safety rests on the animal studies, the food-additive evidence base and decades of widespread use — not on a large dedicated human sensitisation study.
Contact allergy has been reported: A 2015 case report in Contact Dermatitis (Aerts et al.) identified xanthan gum as the culprit in a patient investigated for a reaction to a sunscreen. Xanthan gum is not in standard patch-test series and there is no published frequency estimate, so this is reported-but-unquantified rather than demonstrated to be rare.
Eating it and wearing it are different exposures: The E 415 evidence is reassuring but concerns oral intake; the abdominal discomfort EFSA notes at high oral doses has no bearing on topical use. Both bodies of evidence are cited here because both are real, not because one substitutes for the other.
Pregnancy & Nursing — What the Evidence Shows
Available reproductive studies have not identified adverse reproductive effects; dedicated prenatal developmental toxicity data are limited. EFSA’s re-evaluation of xanthan gum as a food additive concluded that no numerical acceptable daily intake was needed and raised no genotoxicity or carcinogenicity concern. Systemic exposure from topical cosmetic use is expected to be very low, because intact xanthan gum is not expected to penetrate intact skin to a meaningful extent. Dedicated clinical studies in pregnancy have not been conducted. Consult your healthcare provider for personalised advice.
Sources & References
Look up this ingredient on each authoritative source:
Safety data compiled from the CIR Safety Assessment of Microbial Polysaccharide Gums (2016), the EFSA re-evaluation of xanthan gum (E 415), Regulation (EC) No 1223/2009 and its Annexes, the EU CosIng database, the ECHA CLP Annex VI list and Classification & Labelling Inventory, published case reports, and SkinSenseDiary internal analysis. No SCCS opinion exists for this ingredient. This is for educational purposes only and does not constitute medical advice. Last updated: September 2026.
How to Spot Xanthan Gum on a Label
Xanthan gum often appears in the latter part of an ingredient list. Its concentration cannot be inferred from that position alone, particularly because ingredients present below 1% may be listed in any order after those above 1%. You will find it in almost anything with a gel or lotion texture — serums, gel-creams, mineral sunscreens, cleansers, masks. There is nothing to do with it: it is not an active, and its presence tells you about how a product is built rather than what it will do for your skin.
Pairing Guide for Xanthan Gum
✓ Works Alongside
Broadly compatible
Xanthan gum is reported compatible with non-ionic, anionic and amphoteric ingredients, and it is unusually tolerant of salt and acid: supplier data sheets describe it as stable across a wide pH range and compatible with high concentrations of electrolytes, including salts and anionic surfactants. That tolerance is a large part of why formulators choose it over thickeners that collapse in those systems.
A database observation, separately
In our database xanthan gum co-occurs with nearly every ingredient we index, and we hold no conflict records for it. Co-occurrence is not evidence of compatibility, and our having no record is not evidence that none exists. This is a formulation and database observation, not toxicological evidence.
Hyaluronic acid, glycerin and other humectants
Commonly formulated together in gels and serums, where xanthan gum supplies the texture and the humectants supply the water-binding. This is a formulation observation, not a claim that the combination performs better than either ingredient alone.
⚠ Use with Care
Cationic ingredients (a formulator's concern)
Xanthan gum is anionic, so cationic surfactants and conditioning polymers can complex with it and cause thinning or precipitation. This affects texture, not safety, and it is a formulation constraint rather than something to manage in your routine. Severity: 1/5.
Any product, if you are patch-test positive
Given how widely it is used, an established allergy to xanthan gum would mean checking labels broadly. It is not part of standard patch-test series, so it can be missed unless specifically tested. Severity: 1/5.
Products Containing Xanthan Gum
Found in 29,465 products in our database — one of the most widely used texture ingredients in our database. Here are some well-known examples (ingredient lists verified via INCI):
CeraVe
Hydrating Facial Toner
Toner
The Ordinary
Multi-Peptide Eye Serum
Serum
La Roche-Posay
Anthelios SPF 50+ Stick
Sunscreen
Paula's Choice
Azelaic Acid Booster
Serum
Avène
Hydrance Aqua Gel Moisturiser
Moisturiser
Eucerin
Anti-Pigment Dual Serum
Serum
Frequently Asked Questions
Is xanthan gum safe in skincare?
The evidence base is substantial. The CIR Expert Panel concluded in 2016 that microbial polysaccharide gums, including xanthan gum, are safe in cosmetic formulations in the present practices of use and concentration, and EFSA's re-evaluation of it as food additive E 415 found no safety concern for the general population and concluded no numerical acceptable daily intake was needed. Those are two different exposure routes, topical and oral, not two confirmations of the same thing. On hazard classification, xanthan gum has no EU harmonised entry under CLP Annex VI; supplier notifications to the ECHA inventory are split, with most reporting it as not classified and a minority reporting H315 and H319. Its very high molecular weight means intact xanthan gum is expected to have very low penetration through intact skin. Allergic contact dermatitis has been reported in isolated cases, so this is a low-concern ingredient rather than a zero-risk one.
Is xanthan gum natural?
It is produced biologically rather than assembled by chemical synthesis. Xanthomonas campestris bacteria are grown in pure culture on glucose or corn syrup and secrete the polysaccharide as they feed; the result is purified, dried and milled. So it is a fermentation product, not a plant extract, and the process is industrial. Whether that counts as natural depends on the definition you use, and natural or synthetic is not in itself an indicator of safety in either direction.
What does xanthan gum do in a product?
It thickens the water phase, which turns a thin liquid into a serum, gel or lotion; it slows the movement of oil droplets and suspended particles, which helps emulsions and mineral sunscreens stay uniform; and it is shear-thinning, meaning it is viscous at rest and more fluid under the friction of application. That is why a gel-cream feels thick in the jar and light on the skin. Most of what xanthan gum does happens in the bottle rather than on your skin.
Can xanthan gum clog pores?
No comedogenicity concern is established for xanthan gum, and it is not lipophilic. That is an absence of evidence rather than a demonstration that it cannot contribute to congestion, so we do not describe it as non-comedogenic. We also do not cite a use concentration in support of that: CIR reports use at 0.001 to 6%, so claims that it is only ever used at trace levels are not supportable.
Can xanthan gum cause a reaction?
Allergic contact dermatitis has been reported. A 2015 case report in Contact Dermatitis identified xanthan gum as the culprit allergen in a patient investigated for a reaction to a sunscreen. Xanthan gum is not part of standard patch-test series and no published frequency estimate exists, so the honest answer is that reactions are reported but unquantified. The absence of a frequency estimate is not evidence that the frequency is low. If you have persistent dermatitis you cannot explain, xanthan gum is worth raising with your dermatologist as a patch-test candidate.
Is it the same xanthan gum that's in food?
Yes. It is food additive E 415, and the material used in cosmetics is the same polysaccharide. The food evidence is genuinely relevant, but it describes a different exposure route: EFSA assessed dietary intake and explicitly states that its conclusion does not extend to other uses. The abdominal discomfort EFSA notes at high oral doses has no bearing on applying it to skin.
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