... concentrations of melanin in dark-skinned individuals shield the keratinocytes from the ultraviolet radiation required to generate vitamin D in skin [38]. In addition, the production of vitamin D in skindiminishes ... in the immediate vicinity of the site of the microbial breach [28-30]. In addition, catheli-cidin plays a role in epithelial repair by triggering epithe-lial growth and angiogenesis [32]. The ... percentage is higher in the winter, in the aged, in the obese, in the sun-deprived, in the dark-skinned, and in more poleward pop-ulations [40,41]. However, seasonal variation of vitaminD levels even...