Although melanin is capable of efficiently absorbing and scattering electromagnetic radiation, melanin itself, as well as its precursors, are also capable of generating free radicals and other oxidizing species, such as singlet oxygen (1O2), after absorbing photons in the UV and visible ranges. In addition to generating several reactive species by electronic excitation, melanin also acts as a sacrificial antioxidant agent, by reacting and neutralizing these species [1]. 1O2, for example, can add to the indole rings present in the structure of melanin, forming hydroperoxides and causing the photobleaching of melanin. The generation of 1O2 in hair fibers depends on the amount and type of melanin, and can explain the color change that happens after persistent sun exposure [2], as well as, it can be used to develop novel methodologies to precisely reduce hair color, without affecting significantly the mechanical properties of the hair fiber and of the cuticle structure [3]. In human skin, melanin is one of the most important protecting agent against the excess of sun exposure. However, melanin is also involved in excited state and free-radical reactions. Skin of color (SOC) individuals synthesize eumelanin granules in greater amount and bigger size than fair-skinned people, being better protected against UVR, but being susceptible to several skin disorders, including melasma, which can be correlated to the effects of melanin photosensitization with Visible Light (VL). VL can damage melanocytes through melanin photosensitization and 1O2 generation, thus decreasing cell viability, increasing membrane permeability, and causing both DNA photooxidation and necro-apoptotic cell death. UVA (355 nm) and visible (532 nm) light photosensitize 1O2 with similar yields, and pheomelanin is more efficient than eumelanin at generating 1O2 and in resisting photobleaching. Although melanin can protect against the cellular damage induced by UVB, exposure to VL leads to mutagenic DNA lesions (i.e., Fpgand Endo III-sensitive modifications) [4]. These data demonstrate the types of damage that an overexposure to VL can cause in human skin. Novel sun screen technology should favor broad spectrum protection and personalized formula, especially for SOC people that needs stronger photoprotection in the visible range, compared with fair-skin people that needs stronger protection in the UVB [1].