What is the normal pH of skin?

The normal pH of skin is indeed in the acidic range, typically between 4.5 and 5.5. This acidic environment is crucial for maintaining the skin's barrier function, as it helps inhibit the growth of harmful bacteria and fungi, thereby protecting against infections. The acidic pH supports the function of enzymes and other proteins involved in the skin's barrier and immune responses.

The skin's surface acid mantle is primarily composed of lipids, amino acids, and lactic acid, which contribute to this acidity. Maintaining this pH is vital for overall skin health, and any disruption to this balance, such as from harsh soaps or environmental factors, can lead to skin irritation, increased susceptibility to infections, and other dermatological issues.