Natural hair colors
Natural hair color can be black, brown, blond, or red. Hair color is typically genetically associated with certain skin tones and eye colors.
Brown hair
Main article: Brown hair
Brown hair is characterized by higher levels of eumelanin and lower levels of pheomelanin. Of the two types of eumelanin (black and brown), brown-haired people have brown eumelanin; they also usually have medium-thick strands of hair. Brown-haired people are often known asbrunettes/brunets.
Black hair
Main article: Black hair
Black-like hair is the darkest and most common hair color. It has large amounts of eumelanin and is less dense than other hair colors. It can range from soft black to blue-black or jet-black.[2]
Blond hair
Auburn hair ranges along a spectrum of light to dark red-brown shades. The chemicals which cause auburn hair are eumelanin (brown) andpheomelanin (red), with a higher proportion of red-causing pheomelanin than what is found in average brown hair. It is most commonly found in individuals of Northern and Western European descent.Auburn hair
Chestnut Hair
Chestnut hair is a hair color which is a reddish shade of brown hair. In contrast to auburn hair, the reddish shade of chestnut is darker. Chestnut hair is common among the native peoples of Northern, Central, Western, and Eastern Europe.
Red hair
Red hair ranges from light strawberry blonde shades to titian, vivid oranges, copper, and less commonly "true" red. It is caused by a variation in the Mc1r gene and is recessive.[3] Red hair has the highest amounts of pheomelanin, around 67%, and usually low levels of eumelanin. At 1-2% of the population, it is the least common hair color in the world. It is most prominently found in Scotland and Ireland. Scotland has the highest proportion of redheads; 13 percent of the population has red hair and approximately 40 percent carries the recessive redhead gene.[4][5][6]
Grey and white hair
Grey or white hair — sometimes colloquially called "salt and pepper" — is not actually a true grey or white pigment. In fact, it is clear due to lack of pigmentation and melanin. The clear hairs appear as grey or white because of the way light reflects from the hairs. Grey hair color typically occurs naturally as people age (see "Effects of aging on hair color", below). For some people this can happen at a very young age (for example, at the age of 10). The same is true for white hair. In some cases, grey hair may be caused by thyroid deficiencies,Waardenburg syndrome or a deficiency of B12.[7]
The Journal of Investigative Dermatology published a study in 2005 which found that Caucasian people will begin to grey in their mid-30s while Asian people begin greying in their late thirties, but most African-American people can retain their original hair color until their mid-forties.[8] People with albinism may have white hair due to low amounts of melanin.
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