Skin-identical lipids , as the name suggests, also appear naturally in your skin. The upper layer of your skin consists of cells (corneocytes) that are surrounded by a mix of lipids, such as ceramides, cholesterol and free fatty acids. In the right proportions they form a compact structure and thus an intact skin barrier. If your skin barrier lacks essential lipids, you will get dry skin because water from the skin can evaporate more easily. Adding ingredients such as ceramides, cholesterol and free fatty acids to your creams can contribute to a constructive support of the skin barrier.