Why does the skin tan after exposure to UV rays?
The skin contains a pigment called melanin. It colors the skin, imparting the variety of skin tones we all recognize. Melanin blocks at least some of the UV rays from penetrating the skin. After repeated or prolonged exposure to UV rays, the skin produces more melanin. Consequently, the skin darkens, or tans, which in turn protects the skin to a certain degree. Who is most susceptible to sunburn? Persons with certain pigment disorders (such as albinism) and persons with fair skin are at highest risk of suffering a burn. The American Academy of Dermatology classifies skin types into six categories (in terms of susceptibility to sunburn) for skin colors ranging from fair to black. This is called the Fitzpatrick classification. These skin types are as follows: Types 1 and 2: High Susceptibility to Sunburn • Individuals with Skin Type 1 have very fair skin (pale or milky white), blond or red hair, and possibly freckles. Such persons can suffer a burn in less than one-half hour when exposed
