The pigment primarily responsible for hair color is melanin.
Types of Melanin in Hair
There are two main types of melanin that contribute to hair color:
- Eumelanin: This type of melanin produces brown and black hair colors. A higher concentration of eumelanin results in darker hair shades.
- Pheomelanin: This melanin contributes to red and yellow hair tones. The presence of pheomelanin, along with the amount of eumelanin, determines the overall hair color.
The amount and ratio of these two melanins determine the final hair color. For example, an abundance of eumelanin leads to dark brown or black hair, while a higher proportion of pheomelanin results in red or blonde hair. A balance of both creates various shades in between.
Melanin Production and Hair Color
Melanin is produced by specialized cells called melanocytes located in the hair follicles. During the anagen (growth) phase of the hair cycle, melanocytes actively produce and transfer melanin to the hair shaft, resulting in pigmented hair. A decrease in melanocyte activity or a reduction in melanin production leads to graying or whitening of hair.
References Supporting the Answer
- MedlinePlus Genetics: Hair color is determined by the amount of a pigment called melanin in hair. An abundance of one type of melanin, called eumelanin, gives people black or brown hair. (https://medlineplus.gov/genetics/understanding/traits/haircolor/)
- Cleveland Clinic: Melanin is present in human...hair and is responsible for your unique...hair color. (https://my.clevelandclinic.org/health/body/22615-melanin)
- Wikipedia: Two types of pigment give hair its color, black-brown eumelanin and red-yellow pheomelanin. Generally, the more melanin present, the darker the hair. (https://en.wikipedia.org/wiki/Human_hair_color)
