SENSITIVE SKIN AND MOISTURIZATION

Skin moisturization is a state of the surface of the skin, which is more often recognized by the individuals when moisturization is lacking, and when one has skin conditions that can be called dry, very dry, rough, or even ichthyotic. The moisturization of the upper part of the skin is likely to be dictated by the presence of lipids, water, urea, and other compounds. It can also be considered to be the consequence of how well the outer envelope of the skin opposes the evaporation. Several authors have undertaken to measure the water content of the outer surface of the skin. Other authors have emphasized the importance of the so-called transepidermal water loss (TEWL), expressed as grams of water per square meter per hour. The capability of the skin to oppose water evaporation can be equated to its capability to provide an overall barrier. The measure of TEWL provides information on the changes in moisturization induced by a treatment, which does not affect the barrier, and on changes of the barrier properties induced by a treatment, which does not affect moisturization. Skin sensitivity is a self-assessed diagnosis of a physiological state that lacks rigorous clinical definition, complete etiological analysis, and accurate diagnostic tools. This undesirable state of the skin is characterized by a disagreeable feeling on the surface of the skin or by the observation of hyper-reactivity of the skin when it is exposed to mild environmental conditions such as water, wool fabrics, or