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How does the stratum corneum reduce water loss from the body?

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Learn how regenerative properties of the skin helps to protect the human body from the external environment — human skin Human skin, whose cells are generated continuously by the body, serves as a protective barrier between the inside of the human body and the environment.

The stratum corneum, the outermost layer of the epidermis, functions as a vital barrier that prevents the outward loss of water from the body. This protective mechanism is primarily located in the lower part of the horny layer.123

In this region, the spaces between the compacted, keratin-filled cells are tightly packed with lamellae of waxy lipids. These lipids are produced within membrane-coating granules in the underlying living epidermal cells and are discharged into the intercellular spaces. These lipid components are arranged in bilayers that act as an impermeable barrier, effectively blocking the outflow of water into the environment. By maintaining this extracellular matrix of lipid platelets, the stratum corneum ensures the body retains necessary hydration while protecting underlying tissues from environmental injury.13425