Serine

An amino acid that helps maintain skin hydration and supports the skin barrier. Serine is a key component of the skin's Natural Moisturizing Factor (NMF), accounting for a significant portion of the free amino acids in the stratum corneum. As a hygroscopic molecule, it attracts and binds water from the environment and deeper epidermal layers, thereby enhancing skin hydration, elasticity, and supporting the integrity of the skin barrier. It also serves as a precursor for other NMF components and contributes to protein synthesis, maintaining cellular structure and function.

Serine is a naturally occurring alpha-amino acid and is generally considered very safe for cosmetic use. The Cosmetic Ingredient Review (CIR) Expert Panel has assessed Serine and affirmed its safety as a cosmetic ingredient, finding no evidence of irritation or sensitization potential at typical use concentrations.

Look for products with Typically used in cosmetic formulations at concentrations ranging from 0.05% to 2% when included as a humectant or part of an NMF complex for skin hydration benefits. for clinical efficacy.