Vitamin D, the gut microbiome and inflammatory bowel disease

Vitamin D has an important role in bone metabolism but recently has been recognized as an immunoregulator, and this has led to investigations on the e?ect of Vitamin D supplementation in various autoimmune diseases and its anti?in?ammatory e?ects. Tere is some evidence that Vitamin D can regulate gastrointestinal in?ammation. In addition, previous studies have shown that Vitamin D can a?ect the gut microbiome. Te aim of this review is to evaluate the e?ect of Vitamin D on in?ammatory processes, especially its relation to the in?ammatory bowel disease (IBD) and gut microbiome. Tere is some evidence that Vitamin D can regulate gastrointestinal in?ammation, with epidemiological studies showing that individuals with higher serum Vitamin D have a lower incidence of IBD, particularly Crohn’s disease. Vitamin D changes transcription of cathelicidin and DEFB4 (defensin, beta 4) that can a?ect the gut microbiome. Several cell types of the immune system express Vitamin D receptor, and hence the use of Vitamin D in immune regulation has some potential. Furthermore, Vitamin D defciency leads to dysbiosis of gut microbiome and reported to cause severe colitis. Vitamin D supplementation is low cost and available and can be a therapeutic option.