A new study from the Journal of Infectious Diseases has found that, in mice, vitamin D improves the health of the intestinal tract and protects it from damage induced by bacterial infection.
The intestinal tract is a semi-permeable barrier that serves as a gatekeeper. The barrier is made of cells known as intestinal epithelial cells, which are joined together by tight junctions that prevent substances from entering through the spaces between the epithelial cells. Ideally, only nutrients should be able to pass through this barrier, while parasites, pathogens, and toxins are kept out.
Under certain conditions, this barrier becomes too permeable, allowing harmful organisms and substances into the blood stream. Increased epithelial permeability due to changes in the tight junctions is found in patients with ulcerative colitis (UC), an inflammatory bowel disease.
The incidence of inflammatory bowel diseases (Crohn’s Disease and UC) has increased over the last couple decades, especially in developed nations. Scientists studying this increase cannot attribute this change only to genetic factors. The increase in incidence is more likely due to environmental alterations, such as disturbances in the microbial flora of the intestines or potentially a deficiency of vitamin D.