The source of the color in the skin, the supply of gums, or even the hair of the head and body, and the lens of the eye is due to the pigment cells scattered in abundance in all those areas, which produce the melanin pigment. The intensity or depth of the color depends on the concentration of pigment secreted by these cells, which depends mainly on the genes of the individual.
Gums can be depigmented surgically or by laser.