Anhydroxylitol
Also known as 1,4-Anhydroxylitol, Anhydro-D-xylitol, Cyclic xylitol
“CIR Expert Panel says: safe as used in cosmetics.”
Anhydroxylitol (CAS 53448-53-6) is a cyclic dehydration product of xylitol formed by intramolecular etherification. The CIR Expert Panel for Cosmetic Ingredient Safety assessed it in a 2025 final report alongside six related saccharide ingredients and concluded it is safe in cosmetics at present practices of use and concentration, with no concentration limits or conditions (IJT 44(4 Suppl):93S-120S, PMID 41243164). Anhydroxylitol is a component of the commercial humectant blend Aquaxyl (xylitylglucoside-anhydroxylitol-xylitol); two in vivo skin hydration studies (PMIDs 36541033, 19250164) show significant moisturizing efficacy for the blend, though anhydroxylitol is not isolated as a standalone test substance in those studies. No safety concerns were identified at cosmetic use concentrations.
Humectant: draws and retains moisture in the stratum corneum
Component of Aquaxyl blend shown to reduce skin roughness (Ra) and improve skin microrelief in vivo
Water-soluble and highly hygroscopic; well-suited for aqueous cosmetic formulations
Structurally derived from xylitol; shares favorable tolerability profile of sugar alcohol class
- · No dermal safety concerns at cosmetic use concentrations; CIR Expert Panel imposed no concentration limits or conditions
- · In high concentrations, slight eye irritation has been reported; not a concern at typical cosmetic use levels
Safety Assessment of Anhydrogalactose, Anhydroglucitol, Anhydroxylitol, Arabinose, Psicose, Saccharide Hydrolysate, and Saccharide Isomer…
“Anhydrogalactose, Anhydroglucitol, Anhydroxylitol, Arabinose, Psicose, Saccharide Hydrolysate, and Saccharide Isomerate are safe in cosmetics in the present practices of use and concentration described in this safety assessment.”— Int J Toxicol 44(4 Suppl):93S-120S, 2025; PMID 41243164; abstract/conclusion