What is the primary function of the stratum corneum in the skin?

The primary function of the stratum corneum is to serve as a protective barrier. This outermost layer of the epidermis is composed of dead skin cells that are tightly packed together, forming a resilient shield that protects underlying layers of skin from environmental damage, pathogens, and dehydration. The stratum corneum plays a critical role in maintaining water homeostasis within the skin, preventing transepidermal water loss and helping to keep the skin hydrated and functioning properly.

By providing this barrier function, the stratum corneum supports overall skin health and integrity. Other layers of the skin contribute various functions, such as elasticity or pigmentation, but the unique structure and composition of the stratum corneum are specifically designed for protection, making it essential for the first line of defense against external factors.