Melanin is a compound derived from the amino acid, tyrosine. It provides pigment to most animals, including humans. In people, melanin determines skin color. People with high amounts of melanin tend to have darker skin, whereas people with less melanin have lighter skin. Melanin is also important for many different aspects of human health and has a wide range of effects on your body.
People with little to no melanin in their skin suffer from a condition called albinism and are known as albinos. Albinism results from a deficiency in the enzyme required to produce melanin, causing a lack of pigmentation of the skin, eyes, ears and hair. According to MayoClinic.com, people with albinism are at an increased risk for skin cancer because melanin acts as a natural sunblock, protecting your skin from the powerful UV rays of the sun.
There are several forms of melanin in your body, including neuromelanin, produced in your brain. Scientists do no fully understand the function of neuromelanin; however, its production appears to increase as you age. According to the European Synchrotron Radiation Facility, or ESRF, one proposed function of neuromelanin is that it helps your body maintain a balance of metals, assuring you do not have too much or too little in your blood stream, which can have negative consequences.
Although not clearly understood, melanin appears to play a role in your ability to hear properly and is important for the overall function of your inner ear canal. According to a 1994 study published in the journal of "Pigment Cell Research," individuals who suffer hearing loss or are deaf lack adequate melanocytes, which are cells found throughout your body that are responsible for producing melanin. According to the researchers, a lack of melanocytes in the inner ear results in cochlear impairment, or hearing loss, although the reason is not clear.
High levels of melanin in your body increase your risk for developing a vitamin D deficiency, according to Palomar College. You obtain vitamin D primarily through sunlight. When you expose your skin to sunlight, the UV rays from the sun trigger vitamin D production in your body. Melanin blocks UV rays, leaving people with darker skin more susceptible to a vitamin D deficiency. This can cause other conditions such as rickets and osteoporosis.
- "Human Anatomy and Physiology"; Elaine N. Marieb; 2004
- MayoClinic.com: Albinism
- ESRF; The Metallobiology of Neuromelanin Pigment in the Human Brain Studied by Synchrotron X-ray Microspectroscopy; S. Bohic et al.; 2008
- "Pigment Cell Research"; Effects of Mutations at the W Locus (c-kit) on Inner Ear Pigmentation and Function in the Mouse; J. Cable et al.; Feb 1994
- Palomar College: Skin Color Adaptation