What is the function of the stratum corneum?

The stratum corneum serves a critical function as the outermost layer of the epidermis, primarily acting as a barrier to protect the underlying tissues. This layer is composed of dead skin cells that have undergone a process known as keratinization, where cells are filled with keratin, a tough, protective protein. This keratinized layer helps prevent the entry of pathogens, chemicals, and other harmful substances while also reducing water loss from the body, thereby maintaining hydration and overall skin integrity.

The structure and composition of the stratum corneum are specifically adapted for these protective roles, making it essential for skin health and resilience. By effectively functioning as a barrier, it plays a key role in protecting the lower layers of skin, wherein important cellular processes occur and where the skin’s various functions are regulated. Understanding the function of the stratum corneum emphasizes the importance of maintaining its health in skincare practices.