Melanin is the natural pigment that gives colour to human skin, hair and the iris. It provides protection against

Melanin is a natural pigment produced by melanocytes in the skin, hair, and eyes. Its primary biological function is photoprotection, specifically acting as a physical and chemical shield against ultraviolet (UV) radiation [5]. Melanin absorbs UV photons, dissipating the energy as heat and preventing the radiation from penetrating deeper into the skin layers where it could cause DNA damage, mutations, or skin cancer [3]. Research indicates that higher concentrations of melanin, such as in darker skin tones, are significantly more effective at inhibiting UVB penetration compared to lighter skin [2]. While the sun emits a broad spectrum including infrared and radio waves, melanin's evolutionary adaptation is specifically linked to regulating UV penetration to prevent sunburn and nutrient photolysis while balancing vitamin D synthesis [1]. Therefore, it provides critical protection against ultraviolet radiation.

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1. [5] https://www.sciencedirect.com/science/article/pii/S1389556721000022
2. [3] Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 19: Ozone Depletion > OTSNE $$FUETION > p. 267
3. [2] https://pmc.ncbi.nlm.nih.gov/articles/PMC3400707/
4. [1] https://pmc.ncbi.nlm.nih.gov/articles/PMC3709783/