Vitamin D and inflammatory bowel disease

This chapter reviews the immunoregulatory role of vitamin D and its effect on the pathology of inflammatory bowel disease (IBD). Following this, it discusses the epidemiological evidence connecting vitamin D deficiency to IBD severity and the data from animal models of experimental IBD. It also proposes the vitamin D hypothesis, which suggests that vitamin D status may be an environmental factor involved in the development of IBD. Finally the chapter reviews the current treatment options for IBD patients and explains how vitamin D might be used as an alternative or a supplemental treatment for patients with IBD. Vitamin D, in vitamin-D-insufficient patients, and its active metabolites and analogs could be a safe and effective adjunct to the therapies available to treat or prevent IBD. Unfortunately, clinical interventions have not been done to look at the effects of vitamin D on IBD disease in humans; based on the extensive data in animal models several studies have been proposed. Issues that need to be addressed include-defining the appropriate dose of the vitamin D compound to be used, effect of other therapies a patient is on, and whether or not patients with either Ulcerative colitis or celiac disease or both can benefit.