So far, it has been identified that the VDR-Vitamin D axis plays the key roles in IBD (Del Pinto et al. 2017), gut Vitamin D regulation (Barbáchano et al. 2017), microbiome homeostasis, epithelium and mucosal regulation (including immune regulation) (Kanhere et al. 2018), sterol metabolism (Ridlon and Bajaj 2015), and autophagy regulation (Sun 2016). Here, VDR is linked to inflammatory bowel disease.