Gut Microbiota in IBD: The Beneficial and Adverse Effects of Diet and Medication

Background: Inflammatory bowel disease (IBD) is a global disease with a considerable increase in prevalence and the impact on the health and well-being of patients suffering from this condition is vast. Diet has been suspected of being a contributor to IBD severity as well as intake of antibiotics. Methods: A literary search was conducted on the most recent studies on the subject of IBD, diet, and medical treatment to identify high-quality research findings within this area of research. Research published within the last decade was prioritized. Studies in English language were included in the search, and the knowledge gained was synthesized in the review. Results: Dietary patterns, specifically intake of Westernized diets, were associated with increased inflammation and increased disease severity in patients suffering from IBD, specifically patients suffering from Crohn’s disease (CD). A co-administration of pre- and probiotics was found to contribute to disease remission in ulcerative colitis patients, however, to a lesser extent in patients with CD. A bidirectional effect on the intestinal microbiome was seen as a result of intake of the medicines used for the treatment of IBD patients, which affects both bioavailability of the drug and efficacy of the treatment. The baseline composition of the intestinal microbiome in IBD patients dictates their response to the different treatments. Conclusions: Diet and medical treatment both have a large impact on the architecture of the intestinal Microbiome in IBD patients and are, as such, both essential to understand to enable individualized and optimized treatment.