ABSTRACT
The skin being the largest organ covers the entire exterior of the body and thus forms a protective barrier in between the human body and its environment. This tough and dry exterior signifies the physical character of the skin. The uppermost layer of the skin is a multilayered structure called the stratum corneum. The top three to five layers of stratum corneum undergo progressive desquamation. The morphology and thickness of stratum corneum is different at various body sites (1-3). The skin maintains characteristic physicochemical features such as structure, hydration, temperature, pH, and oxygen and carbon dioxide gradients. Changes in any of these factors impact the overall physiology of the skin. The acidic nature of the skin was discovered by Heuss in 1892 (4) and was later validated by Schade and Marchonini in 1928, (5) who underlined acidity as its protective feature and called it the “acid mantle.” Current literature indicates that the skin surface pH is largely acidic between 5.4 and 5.9 (6).
