Hydrogenated castor oil hydrostearate, the hydrogenated (hardened) castor oil with a high content of salts or esters of 12-hydroxystearic acid (12-hydroxy-1-octadecanoic acid), is used in cosmetic formulations. The oil acts as a viscosity regulator (increases or decreases the viscosity of cosmetic products). "Hydrogenated" means treated with hydrogen (hydrogenated).