Diet in Irritable Bowel Syndrome (IBS): Interaction with Gut Microbiota and Gut Hormones

Abstract

Diet plays an important role not only in the pathophysiology of irritable bowel syndrome (IBS), but also as a tool that improves symptoms and quality of life. The effects of diet seem to be a result of an interaction with the gut bacteria and the gut endocrine cells. The density of gut endocrine cells is low in IBS patients, and it is believed that this abnormality is the direct cause of the symptoms seen in IBS patients. The low density of gut endocrine cells is probably caused by a low number of stem cells and low differentiation progeny toward endocrine cells. A low fermentable oligo-, di-, monosaccharide, and polyol (FODMAP) diet and fecal microbiota transplantation (FMT) restore the gut endocrine cells to the level of healthy subjects. It has been suggested that our diet acts as a prebiotic that favors the growth of a certain types of bacteria. Diet also acts as a substrate for gut bacteria fermentation, which results in several by-products. These by-products might act on the stem cells in such a way that the gut stem cells decrease, and consequently, endocrine cell numbers decrease. Changing to a low-FODMAP diet or changing the gut bacteria through FMT improves IBS symptoms and restores the density of endocrine cells.

Irritable bowel syndrome dietary modifications - what to forbid and what to recommend?

“…Regular meals, taking time to eat and avoiding missing meals or leaving long gaps between eating are not only basics rules of healthy diet, but also play the significant role in IBS management. [6] Furthermore, mentioned rules are beneficial in all subtypes of IBS. Apparently there is a higher prevalence of food trigger reactions in patients with IBS-D.…”

“…The most common examples are: coffee, fried and sweetened products, alcohol and sweets. [6] The aim of this study was to describe dietary modifications that alleviate symptoms and improve quality of life. Study material consisted of publications, which were found in PubMed, ResearchGate and Google Scholar databases.…”

Nutritional Management of Gastrointestinal Diseases and Disorders

“…This low enteroendocrine-cell density appears to be caused by both the low density of intestinal stem cells and the low rate of stem cells differentiation into enteroendocrine cells [15]. In one of the articles in this issue, it is speculated that by-products resulting from bacterial fermentation of the diet interact with gut stem cells causing the low differentiation rate into endocrine cells, leading to the manifestation of gastrointestinal dysmotility, visceral hypersensitivity, and abnormal gastrointestinal secretion [1]. This in turn would give rise to the symptoms characteristic of IBS.…”

“…The intestinal bacterial profile in patients with IBS differs from that in healthy subjects, with IBS patients having a lower bacterial diversity (dysbiosis). Patients with IBS who do not respond to dietary management suffer from severe dysbiosis [1]. The article in this issue by Catinean et al [18] indicates that a mixture of spores from five Bacillus spp.…”

“…These neuroendocrine peptides/amines regulate the gastrointestinal motility, secretion of enzymes and gall-bladder acids, absorption of nutrients, water and electrolytes, the proliferation of intestinal cells, local immune defences, and appetite. Furthermore, they interact and integrate with the enteric, autonomic, and central nervous systems [1].…”