Skin constantly renews itselfThe skin provides a dynamic barrier between your body's internal environment and the outside world. Water is supplied to the skin by blood flowing through the dermis , the inner layer of skin; water is lost from the epidermis, especially in a dry environment. Water is needed to maintain skin hydration and when you become seriously dehydrated your skin appears dull and is less elastic. Dermatologists use specific wavelengths of UVA and UVB in carefully controlled doses to reduce skin inflammation, a valuable treatment for some skin conditions. The basic principles of keeping skin healthy are mainly common sense.

Source: CNN February 27, 2019 09:11 UTC