Phaeomelanin in Hair:
Quick Facts


One of the two out of five basic types of melanin pigment that is primarily responsible for red and blonde hair colors. Unlike eumelanin, which produces brown and black hair, phaeomelanin (or pheomelanin) creates a spectrum of warm hues ranging from strawberry blonde to deep auburn (in conjunction with the level of uemelanin present, of course). Additionally, phaeomelanin can be found concentrated in the lips, nipples and areolas, glans of the penis, and vagina.

Chemical Composition and Formation Basics

Phaeomelanin is composed mainly of benzothiazine units. Its production in hair follicles begins with the amino acid tyrosine, which is converted to dopaquinone by the enzyme tyrosinase. In the presence of cysteine, dopaquinone forms cysteinyldopa compounds, which eventually lead to phaeomelanin.

Why Any of This Matters

  • Hair Color Diversity: Phaeomelanin is the reason there exists such a wide range of red and blonde hair colors in the human population. (And in any eukaryote with melanocytes, to be honest.)
  • UV Sensitivity: Hair with high phaeomelanin content (like red hair) offers less natural UV protection compared to hair with more eumelanin. The same goes for skin.
  • Genetic Factors: The amount of pheomelanin in hair is largely determined by genetics, particularly variants of the MC1R gene.
  • Oxidative Stress: Phaeomelanin production in hair follicles may influence local oxidative stress levels, potentially affecting hair health and growth.
  • Aging and Hair Color: As one ages, pheomelanin production often decreases, contributing to the graying process.

Understanding phaeomelanin in hair is but one aspect for comprehending human pigmentation, its genetic basis, and potential implications for hair care and protection against environmental factors such as UV radiation, as well as associated health risks.




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