Tanning response is strongly determined by constitutive pigmentation and is more prominent with darker skin color. The classification of skin phototypes categorizes different constitutive pigmentation and its abilities to burn or tan in response to sun exposure. Skin photoypes are classified into six categories, type I-VI. Type I represents those with very fair skin who will always burn and never tan with exposure to the sun while type II are individuals who tan minimally but with difficulty and burn easily. Skin type III burn moderately and tan moderately and uniformly. Skin type IV individuals burn minimally and always tans well while those of skin type V with very dark skin, rarely burn and tan profusely. The last skin type, VI, represent individuals who tan profusely upon exposure and never burn (Brenner and Hearing, 2007). In Young’s (et al.,
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In Miyamuera’s (et al., 2010) study, the effects of various wavelengths of ultraviolet was compared through repeated exposure of human skin to suberythemal doses of ultraviolet A and/or ultraviolet B for two weeks. The study showed that in the ultraviolet B tanned skin; there was a higher melanin content and ultraviolet-protective effects against DNA damage as there was in the ultraviolet A tanned skin. The tanning from ultraviolet A was caused by the photooxidation of existing melanin and redistribution of pigment granules, thus tanning was seen in both exposures of ultraviolet A and B. However, ultraviolet B increases pigmentation coverage and involves the production of new melanosomes, as it stimulates melanocytes to up-regulate melanin synthesis. The study concluded that ultraviolet A tanning had no photoprotective effects in comparison to ultraviolet B
In Miyamuera’s (et al., 2010) study, the effects of various wavelengths of ultraviolet was compared through repeated exposure of human skin to suberythemal doses of ultraviolet A and/or ultraviolet B for two weeks. The study showed that in the ultraviolet B tanned skin; there was a higher melanin content and ultraviolet-protective effects against DNA damage as there was in the ultraviolet A tanned skin. The tanning from ultraviolet A was caused by the photooxidation of existing melanin and redistribution of pigment granules, thus tanning was seen in both exposures of ultraviolet A and B. However, ultraviolet B increases pigmentation coverage and involves the production of new melanosomes, as it stimulates melanocytes to up-regulate melanin synthesis. The study concluded that ultraviolet A tanning had no photoprotective effects in comparison to ultraviolet B