Melanin is a pigment produced by cells called melanocytes in most organisms. It gives skin, hair, and eyes their color. The variation in color is due to sun exposure, genetic makeup, size of melanocytes, and sometimes the disease condition. The counties with more sun exposure generally have a population with darker skin tones and vice versa. Melanin is found in not just humans but in animals and plants too. In vertebrates, it happens to be a significant pigment. It serves many different biological functions in the human body and is more important than we give it credit for.
Strictly speaking in scientific terms, melanin is a chemical compound made of a complex polymer derived from a type of amino acid, tyrosine. It has hydrogen, carbon, oxygen, and nitrogen. Its chemical formula is, C18 H10 N2 O4. Melanin has two basic forms, eumelanin, which is brownish in color and pheomelanin, which is reddish-brown.
People residing in countries near the equator generally have more melanin in their skin than people living in countries farther in the north and south, away from the equator. Even in one country, this may differ due to the topography of each city. Another reason can be the genetic makeup as well. Melanin is the body’s protection against the harmful sun rays and to prevent it from burning. The tanning that takes place due to the sun is the Ultra Violet A rays, also known as the UVA rays, penetrating the lower layers of the epidermis. Here, they trigger the melanocytes to produce melanin. There are hence, many different complexions amongst humans.
Melanin protects the skin from cancer-causing UV rays. This is also why people living in areas where the sun shines throughout the year have more melanin in their skin naturally to protect them from diseases such as these. So, if you use bleach or use fairness creams, it will likely destroy the melanin on your skin, and it is likely to cause a lot of harm to your skin. Not only this, the presence of melanin ensures protection against skin sensitivity. This also means that skin enriched with melanin will likely get wrinkled in a later age. Melanin keeps the skin protected and firmer for a longer time. Melanin is also the pigment giving freckles their deep, dark color.
Melanin in hair is produced in the stem cells at the base of follicles present on the scalp. Melanin in hair keeps them from graying. When the melanocyte stem cells die, it causes the hair to gray. Another reason for this is a natural buildup of hydrogen peroxide in hair follicles. In younger people, an enzyme called catalase breaks down hydrogen peroxide into water and oxygen. They provide hair with beautiful rich pigments from deep, dark blacks, to brunettes to golden blondes. The rarest of the hair color is red. Redheads are seen in less than 1-2% of the population.
Melanin in eyes also produces beautiful colors, from ocean blues to forest greens, from striking hazels to almond browns and dark blacks. The rarest of them is blue, and people with blue eyes have the least amount of melanin, then comes green and then hazel. The second last one is brown and lastly black eyes. Genetics determines the color of your eyes. Melanin protects the eyes from the sun and other various electromagnetic radiation sources.
Melanin is not just for the color that it provides but has an essential function to protect humans, mainly due to the ever depleting ozone layer and the ever-increasing amount of UV rays making their way to the earth.
Until Next Time,
Team Doctor ASKY!