Gelatin

Gelatin is a denatured collagen-derived film-former/binder used in masks and topical formulations typically at low-to-moderate percentages, and it is generally well tolerated with minimal inherent irritancy. Clinical experience and patch-test data suggest irritation is uncommon, but animal-protein derivatives can occasionally trigger reactions in highly atopic or protein-sensitized individuals, so it cannot be considered fully inert. Given this small but real risk in severely sensitive populations, it fits best as very gentle rather than inert. Safety Notes: In commercial skincare, gelatin is most often used as a film-forming/texture aid in leave-on masks, peel-off masks, and some creams/lotions, with low-end use around 0.05–0.5% for light skin-feel or claim support (often alongside other polymers). The highest consumer-available levels are seen in DIY-style or ready-to-mix peel-off mask powders and strong-setting gel masks where gelatin functions as the primary gelling/film-forming agent, commonly 3–10% depending on bloom strength and desired set. Rinse-off mask formats tolerate the upper end more readily than leave-on products, which typically stay in the low single-digit percent range due to tack/feel and stability constraints.