VDR and colorectal carcinoma: In fact, these correlations mostly result from the interaction between VDR polymorphisms and other factors, such as Ca and vitamin D intake, plasma levels of 1,25-dihydroxyvitamin D3 [1,25(OH)2D3], UV radiation exposure, obesity, and energy intake [29–32].The aim of this study was to analyze the relationship between serum total vitamin D, 25(OH)D3, and Ca levels and VDR polymorphisms in the manifestation of CRC.