Ceramides

Ceramides are lipid molecules that make up roughly 50% of the skin barrier by composition. They form the mortar between skin cells (corneocytes) in the outermost layer of skin, creating a protective barrier that locks in moisture and keeps irritants out. When ceramide levels drop due to aging, harsh cleansing, or environmental stress, skin becomes dry, irritated, and vulnerable.

There are several types of ceramides used in skincare, typically numbered (ceramide 1, ceramide 3, etc.) or labeled by their chemical structure (ceramide NP, ceramide AP, etc.). The most effective formulations contain a blend of ceramides along with cholesterol and fatty acids, mimicking the natural lipid composition of healthy skin.

Japanese brands like Curel (by Kao) have invested heavily in ceramide research and offer some of the most sophisticated ceramide formulations available. Curel is specifically designed for sensitive, ceramide-deficient skin and is a drugstore staple in Japan. Tunemakers and Matsuyama also feature ceramide-focused lines.