seramidien

Seramidien are a group of naturally occurring fatty molecules, specifically lipids, that play a crucial role in the structure and function of cell membranes. They are composed of a sphingoid base linked to a fatty acid. This fundamental structure is essential for maintaining the integrity and fluidity of cell membranes, which are the outer boundaries of all cells.

In the skin, ceramides are particularly abundant in the stratum corneum, the outermost layer of the epidermis. They act as the primary lipid component of the skin barrier, making up approximately 50% of the total lipid content. This lipid matrix, along with corneocytes (dead skin cells), forms a protective barrier that helps to prevent water loss from the body and blocks the entry of harmful external substances. The arrangement of ceramides in a lamellar structure is key to their barrier function.

Disruptions in ceramide levels or structure in the skin have been linked to various skin conditions, including eczema, psoriasis, and xerosis (dry skin). When ceramide production is compromised, the skin barrier becomes weakened, leading to increased transepidermal water loss and greater susceptibility to irritants and allergens. Consequently, ceramides are widely used in skincare products, particularly those designed for moisturizing, barrier repair, and addressing dry or compromised skin. They are often incorporated into creams, lotions, and serums to replenish the skin's natural ceramide content and support its protective functions.