Why Are Red-Haired People at Greater Risk from the Sun?

Melanocytes in individuals with Red Hair Phenotype (RHP) are unable to produce significant amounts of eumelanin (black-brown melanin). Because of genetic variants affecting melanogenesis, they predominantly produce pheomelanin (red-yellow melanin).

Unlike eumelanin, pheomelanin provides little protection against solar ultraviolet radiation and may even enhance its harmful effects.

Why does this happen?

Eumelanin

Eumelanin protects the skin in two complementary ways:
  • It acts as a physical shield, absorbing and scattering part of the incoming UV radiation.
  • Thanks to its powerful antioxidant properties, it neutralizes reactive oxygen species (ROS) generated by UV exposure, thereby limiting oxidative damage to cells.

Pheomelanin

Pheomelanin behaves quite differently:
  • It offers much less photoprotection than eumelanin.
  • It may act as a pro-oxidant, promoting the formation of reactive oxygen species and consequently increasing oxidative damage induced by UV radiation.

As a result, individuals with Red Hair Phenotype (RHP) are particularly prone to sunburn and have a significantly increased risk of developing skin cancers.