Structure of human skin
Our skin essentially consists of three layers: the subcutaneous tissue (subcutis), the dermis and the epidermis. The epidermis is also known as the skin barrier.
The skin barrier is the interface between the human organism and the environment and serves as a barrier both for external influences, such as UV rays, blue light or mechanical stress, and for water and small molecules from the inside to the outside. The skin barrier not only has to protect the body from external impacts, but is also responsible for maintaining the water balance (low TEWL). For beautiful, well-groomed and soft skin, the focus of cosmetics is primarily on the stratum corneum (the top layer of the epidermis), the epidermis and dermis, because they tell us whether our skin is dry or moisturized.