Can VDR help with gut health?

The vitamin D receptor (VDR) is a nuclear receptor that mediates the genomic effects of vitamin D. It is expressed in intestinal epithelial cells and immune cells of the gut mucosa. Through regulation of genes such as *CAMP* (antimicrobial peptide) and *OCLN* (tight junction protein), VDR can help maintain the gut barrier and modulate innate immunity. Some studies suggest that VDR polymorphisms (e.g., rs2228570, rs1544410) may be associated with inflammatory bowel disease (IBD) and irritable bowel syndrome (IBS), but effect sizes are small and findings inconsistent. The evidence is largely mechanistic, coming from cell culture and animal models; human intervention trials with vitamin D show mixed results. A genetic test for VDR variants alone is not clinically useful for gut health – it must be interpreted together with vitamin D status, diet, and microbiome. Caveat: VDR SNPs are not diagnostic; vitamin D supplementation should only be given if deficiency is confirmed. Gut health is influenced by many factors (fiber, probiotics, stress, medications) that far outweigh single gene variants.