Lipid/surfactant compounds as a new tool to optimize skin-care properties of personal-cleansing products

Surfactants are commonly used in personal-care products to increase cleansi ng performance and to create pleasing foam. However, surfactants can also d amage the skin by removing skin lipids and causing corneocytes to swell, re sulting in increased skin roughness and transepidermal water loss. Newly es tablished methods help to quantify these effects in controlled consumer stu dies. In addition, in vitro experiments with skin cell cultures show the po tential inflammatory action of surfactants, which in the in vivo situation may provoke skin irritation. These detrimental effects are even enhanced by frequent treatment with surfactant-based personal-care products. Together with the use of mild surfactant combinations, the addition of surfactant-co mpatible lipid compounds has proved a convenient way of not only counteract ing the negative side effects of surfactants but also exerting positive ski n effects. In a controlled consumer study, analysis of skin lipids after sk in cleansing revealed the lipid-layer strengthening efficacy of lipid/surfa ctant mixtures that can be solubilized in the personal-care formulation or dispersed as waxy particles. As a result, skin roughness after cleansing tr eatment, as measured by fast optical in vivo topometry of the skin, is impr oved, and consumers perceive that their skin is smooth and cared for.