Melanin in darkly pigmented skin can provide an SPF (sun protective factor) of 1.5 - 4. Amount of UV light getting through is 1/SPF, so a SPF of 4 reduces UV radiation by 75%. So the areas without this protective feature are most at risk (palms/soles).
Melanin in darkly pigmented skin can provide an SPF (sun protective factor) of 1.5 - 4. Amount of UV light getting through is 1/SPF, so a SPF of 4 reduces UV radiation by 75%. So the areas without this protective feature are most at risk (palms/soles).
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2671032/