Controversies on vitamin D currently represent a challenging topic in mineral metabolism research. In particular, current guidelines on vitamin D supplementation did not report consistent recommendation and the issue related to beneficial vs harmful effects of loading vitamin D doses did not lead to any firm universal conclusion. Finally, serum and clinical outcomes of vitamin D supplementation, particularly as far as extra-skeletal effect of the hormone, need to be further investigated.
Keywords: extraskeletal; skeletal; supplementation; vitamin D.