Melanin is the name given to a group of substances that determine color in living things. There are three main groups: eumelanin, pheomelanin, and neuromelanin. While eumelanin and pheomelanin are the most common forms of pigment with brown, black, yellow, and red forms, neuromelanin is only found in the brain and has the effect of masking internal structures.

Melanin is a natural pigment that determines the color of human hair. When the production of this pigment slows down, hair can turn gray or white. This is also part of the aging process, but we can still improve our hair color through melanin supplements or certain foods.