Hair Pigmentation: A Research Update
TLDR Hair color is determined by different melanins and changes with age.
The document reviewed research on hair pigmentation, highlighting that hair color is determined by the presence or absence of different melanins, unlike skin color which also involves hemoglobins and carotenoids. The physical properties of the hair shaft only slightly modify hair color. Evolutionary pressures have led to a wide range of natural hair colors among different ethnic groups, from yellow to black, and gray/white hair signifies aging. Melanins in hair are produced in melanosomes by melanocytes through melanogenesis, a complex biochemical pathway. The review summarized findings from the 4th Intercontinental Meeting of Hair Research Societies in 2004.
