What is it?
A thickener made by fermenting a carbohydrate, such as sugar, with the bacterium Xanthomonas campestris, which produces the gum. A small amount turns water into a smooth gel, so it is used to thicken and stabilize lotions, creams, cleansers and makeup, liquid medicines, and many foods, where it is listed as E415.
Key information
- The CIR Expert Panel concluded that xanthan gum is safe as used in cosmetics, where it was reported in 3,470 products.
- Its molecules are too large to be absorbed through the skin in any significant amount.
- The Joint FAO/WHO Expert Committee on Food Additives gave it an acceptable daily intake of "not specified" as a food additive.
More information
Xanthan gum is a polysaccharide, a long chain built from sugars including glucose, mannose and glucuronic acid, that the bacterium makes as it ferments a carbohydrate. In cosmetics it works as a thickener, binder, gel former and emulsion stabilizer. The Cosmetic Ingredient Review (CIR) found it in almost every category of cosmetic product, with 3,470 reported uses in 2012, at up to 6 percent in leave-on products. It is also used to stabilize and thicken water-based medicines.
The CIR Expert Panel reviewed xanthan gum with 33 other microbial gums and concluded in 2012 that they are safe as used. The molecules are too large to pass through the skin in meaningful amounts. Xanthan gum did not irritate rabbit eyes at 1 percent, and there was no evidence of allergic sensitization in human or animal tests. One poorly documented animal study reported skin irritation, which the Panel attributed to the test method rather than the gum. Workers who handled xanthan gum powder at a manufacturing plant showed no significant changes in lung function.
As a food additive, xanthan gum has been evaluated by the Joint FAO/WHO Expert Committee on Food Additives, which assigned it an acceptable daily intake of “not specified,” meaning it saw no need to set a numerical limit. The European Food Safety Authority re-evaluated it in 2017, and in 2023 it found no safety concerns for its use in special medical formulas for infants under 16 weeks old.
On labels it appears as xanthan gum. Modified forms such as xanthan gum crosspolymer and dehydroxanthan gum were covered by the same CIR safety conclusion.
Sources: Cosmetic Ingredient Review: Safety assessment of microbial polysaccharide gums as used in cosmetics (2012); WHO/JECFA: Xanthan gum (WHO Food Additives Series 21); EFSA Journal (2023): Re-evaluation of xanthan gum (E 415) in foods for infants below 16 weeks of age
