SKIN SURFACE HYDRATION CHANGES DURING A MINI REGRESSION TEST AS MEASURED INVIVO BY ELECTRICAL-CONDUCTIVITY

Electrical conductivity was measured in human volunteers af various times during a mini regression test designed to evaluate selected commercially available moisturizers. Analysis of the conductivity values during the treatment and regression phases of the study showed that this instrumental approach is useful for studying the long-lasting effects of moisturizers on the hydration state of the superficial layers of the stratum corneum. Differences in product performance could be explained in terms of the choice of ingredients. Conventional formulations based solely on occlusives or humectants were found to be less effective than those that contained additional active ingredients, such as keratin softeners and keratin-binding factors.