Melanin
Definition
Melanin is the natural pigment produced by melanocytes in the basal layer of the epidermis that gives skin, hair, and eyes their color. There are two main types: eumelanin (brown/black pigment) and pheomelanin (red/yellow pigment). The ratio and amount of these pigments determine an individual's skin tone. Melanin's primary biological function is to protect skin cells' DNA from UV radiation damage by absorbing and dispersing UV light. When the skin is exposed to UV rays, melanocytes increase melanin production — this is the process of tanning. However, melanin distribution can become uneven, leading to hyperpigmentation conditions like sun spots, melasma, and post-inflammatory hyperpigmentation. Darker skin tones have more active melanocytes producing more melanin, which provides greater natural UV protection but also makes the skin more prone to post-inflammatory hyperpigmentation after injury or inflammation.
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