The first part of the study shows that four commercial sun protection SPF 50 products provide statistically significant (all p < 0.021) protection by reducing the amount of UV-induced mitochondrial (mtDNA) damage in human dermal fibroblast skin cells (i.e., 320% protection). mtDNA damage has been shown to be an effective and reliable biomarker of skin damage and plays a key role in the ageing process. The second part of the study investigates a sub-set, namely two of the four commercial sun protection products. Both products significantly protect (both p < 0.014) against the longer wavelength blue light induced decrease in a different biomarker, namely the viability of human dermal fibroblast skin cells.