Introduction
The skin color is very different from person to person. In humans, the color of the skin depends mainly on how much of the pigment melanin is present in the skin. Melanin is a dye (also called pigment) that is produced by cells in the skin, the melanocytes.
There are two different forms of melanin:
- One is eumelanin, which is mainly responsible for the skin color and is rather brown to black,
- And on the other hand the phaeomelanin, which is rather reddish to yellowish and is mainly found on lighter skin types.
The function of melanin is to protect the body from harmful ultraviolet radiation. This explains why people who live in regions with high solar radiation, such as Africa or South America, generally have a darker skin color than people who live in areas where the sun shines less often. The amount of melanin in the skin is actually genetically determined, meaning that everyone practically inherits their skin color from their mother and father.
To a certain degree, however, this can be influenced: However, a person who is light-skinned by reason will never be able to become completely black, as he or she is not predisposed to it. If melanin is completely absent, the skin appears almost white and the eyes reddish (which shows that the amount of melanin also has an influence on our eye color), this condition is called albinism.
- Under increased exposure to the sun, the body can produce a larger amount of melanin up to a certain point and thus adapt to a changed environment.
Depending on the color of the skin, dermatologists differentiate between 6 skin types, which were described by the American family doctor Fitzpatrick and are associated with different characteristics regarding the appearance and behavior of the skin under the influence of the sun:
- Type 1 = the Celtic type: These people have very fair skin, usually blond or reddish hair, light eyes and often freckles.
Under the influence of the sun’s rays, this type reacts either with the formation of new freckles or very quickly with the development of sunburn.
- Type 2 = the Nordic type: This type is characterized by light skin, light eyes and relatively light hair, also freckles are more common here. In contrast to type 1, however, these people become brown, albeit slowly.
- Type 3 = the mixed type: In this type, all skin and eye colors can be present, but the most common shade of brown is present in both characteristics. Freckles are rather rare here, a tan is faster and a sunburn is less likely
- Type 4 = the Mediterranean type: people with this skin type have a darker or olive complexion even when “untanned”, no freckles, dark eyes and dark (i.e. brown or black) hair.
Sunburn rarely occurs under increased solar radiation, but a tan is quickly developed.
- Type 5 = the dark skin type: Here very dark skin, black eyes and black hair are typical, the risk of sunburn is extremely low and a further tan to a very dark brown is very fast.
- Type 6 = the black skin type: This skin type is especially common among the aborigines of Australia and the sub-Saharan region. Both eyes and hair are black and even the skin can be described as black rather than brown. Sunburn practically never occurs with this type.