What is Skin Barrier?

The skin barrier (also called the moisture barrier or acid mantle) is the outermost layer of skin that protects against environmental damage, bacteria, and water loss. K-beauty places enormous emphasis on maintaining a healthy barrier through gentle cleansing, pH-balanced products, and barrier-repairing ingredients like ceramides, cholesterol, and fatty acids. A compromised barrier leads to sensitivity, redness, and dehydration.