Moisturization

Moisturization is a fundamental physiological process responsible for maintaining the hydration and structural integrity of the skin, primarily within the stratum corneum (StatPearls, 2023; J Cosmet Dermatol, 2025). It is not a single molecular target like a receptor or enzyme, but rather a coordinated mechanism involving natural moisturizing factors (NMFs), epidermal lipids such as ceramides, and specialized water-conducting proteins including aquaporin-3 (AQP3) (MDPI, 2024; Annales Pharmaceutiques Françaises, 2011). The primary biological function of moisturization is to preserve skin elasticity and provide a physical barrier against environmental irritants, allergens, and excessive transepidermal water loss (J Cosmet Dermatol, 2025). When this process is compromised, it results in clinical conditions such as xerosis, atopic dermatitis, and psoriasis, characterized by an impaired skin barrier (ResearchGate, 2025; PubMed, 2020). Therapeutic interventions, broadly known as moisturizers, aim to restore this balance by using humectants to bind water, occlusives to prevent evaporation, and emollients to repair the lipid matrix (J Cosmet Dermatol, 2025; PMC, 2025). Emerging research focuses on targeting specific molecular pathways, such as filaggrin degradation and lipid processing enzymes, to treat chronic barrier disorders more effectively (ResearchGate, 2025; MDPI, 2024).

Other names

Skin hydrationCutaneous hydrationStratum corneum hydrationEpidermal moisturization

Moisturization is achieved through three primary pharmacological mechanisms: humectancy (drawing water from the dermis or environment into the stratum corneum), occlusion (forming a physical barrier to prevent transepidermal water loss), and emolliency (filling intercellular spaces to smooth the skin surface and restore lipid integrity).