Vitiligo

The colour of the skin is caused by the pigment melanin produced by cells in the epidermis called melanocytes. The retina of the eye also contains melanocytes giving it its colour. Having blue eyes means that the content of melanin in the eyes is low. The formation of melanin requires the presence of the amino acid tyrosine and the enzyme tyrosinase.
The skin's production of melanin is increased when it is exposed to ultraviolet light causing the skin to get darker. This also happens in coloured people even though it is more difficult to observe. The darker the skin is the more conspicuous the vitiligo is. Some people suffer from an inheritable pigment disease called albinism. They totally lack the ability to produce melanin and therefore they have a completely light skin, white hair, and reddish eyes. They are also more vulnerable to the ultraviolet radiation of the sun since the skin produces melanin as a protection against the harmful effects of the ultraviolet light from the sun.
It is said that 1% or a maximum of 2% of the earth's population is struck be vitiligo. The disease is not dangerous or contagious but for cosmetic reasons it is often a big strain. It can come at all ages but most frequently it starts in young people. It looks like vitiligo in some cases might be inherited but this is not at all the rule.
The disease often begins with a few, small, white, often symmetrically placed spots spreading to the hands, the upper body, the face, or other places. Some people only get white spots in one side of the body. If the spots are in the located to the scalp, the hair in these places will often be entirely white. Most often the spots spread; this can happen slowly during several years but it can also happen relatively quickly. The disease might also pause for several years.
The white spots in vitiligo is caused by the destruction of the melanocytes. Cases have been reported in which the person's own immune system has produced the antibodies attacking the melanocytes. People that suffer from autoimmune diseases more frequently suffer from vitiligo than the rest of the population but there are no satisfactory conclusions for this phenomenon.
Some scientists assume that the melanocytes also might be destructed for other reasons. The body's cells constantly produce a certain amount of hydrogen peroxide as a natural part of the metabolism; the enzyme catalase, however, is capable of decomposing hydrogen peroxide into water and oxygen. Hydrogen peroxide is a cell killer. The white blood cells use concentrated hydrogen peroxide to kill off foreign bodies. In some people who suffer from vitiligo a low level of the enzyme catalase has been found. The level of catalase can be elevated with large doses of vitamin C and this might be a possible explanation for the beneficial effects of vitamin C used to treat vitiligo.
It is also well-known that sufferings like pernicious anaemia; a disease in which the intestines cannot absorbe vitamin B12 - and low gastric acid production is seen more frequently in persons with vitiligo and these are most often women.