Action and Function of Vitamin D in Digestive Tract Physiology and Pathology

Background: The body of biomedical literature on Vitamin D effector mechanisms in gastrointestinal biology and pathophysiology is rapidly expanding. Accordingly, new possibilities of vitamin D biology-based therapeutical intervention in gastroenterological disease are being identified. However, the literature lacks a concise review on these developments, hampering comprehension of the possibilities involved for many in the community. Results: Genetic vitamin D receptor (VDR) polymorphisms and other VDR biology regulation are involved in predisposition to gastrointestinal cancers and might allow tailored strategies for managing those individuals especially at risk, e.g. through vitamin D supplementation. Likewise, modulation of Hedgehog signaling by vitamin D analogues may have promise in combating gastrointestinal cancers or improving barrier function in IBD, but shortage in vitamin D levels may also influence inflammatory conditions of the gut through direct interaction with the mucosal immune system. Evidence justifying population-wide monitoring for vitamin D status is accumulating. Conclusion: There is kaleidoscopic interaction of vitamin D biology with many aspects of gastrointestinal tract biology. Vitamin D appears an attractive target for personalized approaches like precision and P4 medicine.