Current Explorations of Nutrition and the Gut Microbiome: A Systematic Review (P20-032-19)

OBJECTIVES: The ability to measure and describe the microbiome has led to a surge in information about the gut microbiome and its role in health and disease. The relationship between nutrition and the gut microbiome is central, as the diet is a source of microbiota, a source of fuel for the microbiota, and an indicator of the composition of the gut microbiome. We aim to assess the current understanding of the interactions between nutrition and the gut microbiome in healthy adults. A solid understanding of the interactions between nutrition and a healthy gut microbiome will form the foundation for understanding the role in disease prevention and treatment. METHODS: PubMed and Google Scholar searches for review articles relating to nutrition and the gut microbiome in healthy adults led to the inclusion of 38 articles in this systematic review. RESULTS: Much of the research has focused on carbohydrates in the form of dietary fiber, which are fuel for the gut microbiota. The beneficial effects of fiber have centered on Short Chain Fatty Acids (SCFAs) that are required by colonocytes (barrier function), improve absorption (minerals, water), and reduce intestinal transit time (colon cancer). Contrastingly, a low fiber, high protein diet promotes microbial protein metabolism, leading to potentially dangerous by-products that can stagnate in the gut. The bidirectional relationship between micronutrition and the gut microbiome is emerging. The microbiota utilize and produce micronutrients, leading to confounding relationships between nutritional status and biologic micronutrient concentrations, chiefly the B and K vitamins. While promising, the study of non-nutritive food components (polyphenols) and the gut microbiome is in its infancy. The role of other food components (food additives, contaminants) warrant exploration and are a significant research gap to-date. CONCLUSIONS: Diet and nutrition have profound effects on the gut microbiome composition. This, in turn, affects a wide array of metabolic, hormonal, and neurological processes that influence our health and disease. Currently, there is no consensus in the scientific community on what defines a “healthy” gut microbiome. Future research must consider individual responses to diet and the role of diet in the response of the gut microbiome to interventions. FUNDING SOURCES: N/A. SUPPORTING TABLES, IMAGES AND/OR GRAPHS