Advancing human gut microbiota research by considering gut transit time

• Published in: Gut Vol. 72; no. 1; pp. 180 - 191
• Main Authors: Procházková, Nicola, Falony, Gwen, Dragsted, Lars Ove, Licht, Tine Rask, Raes, Jeroen, Roager, Henrik M
• Format: Journal Article
• Language: English
• Published: England BMJ Publishing Group Ltd and British Society of Gastroenterology 01.01.2023; BMJ Publishing Group LTD; BMJ Publishing Group
• Subjects: Bile; Colon; Constipation; Diet; Fatty acids; Feces; Gastric motility; Gastrointestinal Microbiome; gastrointestinal physiology; gastrointestinal transit; Gut microbiota; Humans; intestinal microbiology; Intestinal microflora; Irritable bowel syndrome; Metabolism; Metabolites; Microbiomes; Microbiota; Motility; Nutrition research; Population studies; Recent Advances in Basic Science; Scintigraphy; Small intestine; Variation; gastrointestinal physiology; intestinal microbiology; diet; gastrointestinal transit
• ISSN: 0017-5749; 1468-3288; 1468-3288
• DOI: 10.1136/gutjnl-2022-328166

Accumulating evidence indicates that gut transit time is a key factor in shaping the gut microbiota composition and activity, which are linked to human health. Both population-wide and small-scale studies have identified transit time as a top covariate contributing to the large interindividual variation in the faecal microbiota composition. Despite this, transit time is still rarely being considered in the field of the human gut microbiome. Here, we review the latest research describing how and why whole gut and segmental transit times vary substantially between and within individuals, and how variations in gut transit time impact the gut microbiota composition, diversity and metabolism. Furthermore, we discuss the mechanisms by which the gut microbiota may causally affect gut motility. We argue that by taking into account the interindividual and intraindividual differences in gut transit time, we can advance our understanding of diet–microbiota interactions and disease-related microbiome signatures, since these may often be confounded by transient or persistent alterations in transit time. Altogether, a better understanding of the complex, bidirectional interactions between the gut microbiota and transit time is required to better understand gut microbiome variations in health and disease.