Moisturizer technology versus clinical performance.

The principles of humectancy, emolliency, and occlusion, all central to stratum corneum (SC) maintenance, continue to drive the development of novel moisturizing technologies. Humectants promote water retention within the SC, whereas occlusives generally minimize water loss to the external environment. The complementary occlusive activity of emollients contributes to SC hydration as well. Moisturization technologies, ranging from face care to hand and body care, vary in the types and levels of humectants, emollients (including lipids), and occlusives; accordingly, their therapeutic effects differ as well. Emulsification of these components into a single formulation-the technologies of which are as varied as their individual components-is thought to enhance the aesthetics of the moisturizer and its overall moisturization efficiency. The present article reviews the current approaches to SC moisturization, increasingly viewed as critical to its structural and functional integrity, and to fundamental skin care.