Sorbitol

Sorbitol is a sugar alcohol used primarily as a humectant in leave-on and rinse-off products (often ~1–10% or higher) and is generally well tolerated, including in sensitive-skin formulations. Clinical experience and patch-test data suggest irritation is uncommon, but it can occur in highly reactive or barrier-impaired skin (e.g., eczema) due to osmotic effects or formulation-dependent factors. Given its broad safety profile but non-zero risk in compromised skin, it fits “very gentle” rather than fully inert. Safety Notes: In commercial skincare, sorbitol is often used at very low levels (~0.05–1%) as a secondary humectant/sweetener or processing aid in leave-on creams/serums and rinse-off cleansers. Mainstream moisturizers, toners, and face washes commonly use ~1–10% for humectancy and feel, while high-strength consumer products such as glycerin/sorbitol humectant gels, some hand/body gels, and certain clear soap or cleansing bar bases can reach ~30–70% sorbitol (often alongside other polyols), with the upper end more typical for rinse-off or high-solids gel/bar formats than elegant leave-on facial products.