Low fermentable oligosaccharides, disaccharides, monosaccharides, and polypols diet and irritable bowel syndrome in Asia

FODMAP meal challenge test: a novel investigation to predict response to low-FODMAP diet in non-constipating irritable bowel syndrome

BACKGROUND

Though a low-FODMAP diet improves 50% irritable bowel syndrome (IBS) patients, regional dietary variations, vegetarianism, and long-term nutritional consequences challenge its implementation. We aimed developing a FODMAP meal challenge test (FMCT). We prospectively studied whether (i) high- than low-FODMAP foods produce more breath H2 among IBS patients than controls; (ii) post-meal symptoms relate to breath H2 ; and (iii) novel FMCT predicts response to a low-FODMAP diet?

METHODS

Forty Rome III IBS and 20 healthy controls underwent an eight-hour H2 breath test following a low- (rice, brinjal, corn, and banana [450 Kcal]) and a high-FODMAP meal (wheat, kidney bean, pulse, and card [450 Kcal]). Breath H2 (every 15 min) and symptoms following low- and high-FODMAP meals were recorded. IBS-symptom severity scores were recorded every month for 3-months on low-FODMAP diet.

RESULTS

Forty Rome III IBS (19 Rome IV positive) were comparable to 20 controls in age and gender. IBS patients (n = 39 excluding one H2 non-producer) and controls produced more breath H2 after high- (greater in IBS) than low-FODMAP meal. Post-meal symptoms were commoner in IBS (4/40 [10%] and 27/40 [67.5%] with low- and high-FODMAP, respectively [P < 0.00001]; none in healthy). IBS patients developing post-high-FODMAP meal symptoms produced greater H2 (18 PPM [IQR 10.5-23] vs 6 [0-7.2]; P < 0.001). A positive FMCT (breath H2  > 10 PPM above basal with symptoms following high-FODMAP food) had sensitivity, specificity, and diagnostic accuracy of 78.6%, 66.6%, and 75.6%, respectively, to predict low-FODMAP diet response.

CONCLUSIONS

The novel FMCT predicts response to a low-FODMAP diet in IBS.

The Brain-Gut Clinic in Hospital Universiti Sains Malaysia: Pioneering New Service to Advance Neuro-Gastroenterology and Motility in Malaysia

Neurogastroenterology and motility is a new but advanced subspecialty within gasteroenterology that cater to difficult, persistent and refractory gut-brain symptoms. Hospital USM has the country's first and new state-of-the art motility lab that was recently launched on the 25 May 2023, and is covered in nationwide media. Another first is the Brain-Gut Clinic, established on the 16 November 2022. The clinic is a new concept that builds on unique multiple disciplines in relation to the gut-brain axis. It is hoped that there will be more awareness on the existence of neurogastroenterology and motility among doctors and community, and that more research can be forthcoming to reduce the disease burden.

A low molecular weight brown algae Laminaria japonica glycan modulation of gut microbiota and body weight in mice

Brown algae glycan from Laminaria japonica (LJNP) is a heterogeneous glycan with two apparent molecular weights of 1.1 and 37.3 kDa, and is mainly composed of α β-glucan and a few fucosyl residues. To explore the regulation of gut microbiota and the host, LJNP and 2'-fucosyllactose (2'FL) were compared to investigate their effect on mice via oral administration. Using metagenomic and metabolomic analyses, we found that 2'FL mainly relied on Adlercreutzia equolifaciens and Akkermansia muciniphila to improve gut amino acid and bile acid metabolism, whereas LJNP mainly drove Bacteroides vulgatus and Bacteroides uniformis to regulate gut amino acid metabolism and glycometabolism. Moreover, LJNP showed a weight loss effect and better protection of the intestinal barrier than 2'FL. We further employed LJNP and 2'FL on a germ-free mice model. Interestingly, the body weight management was not microbiome mediated. This study showed that LJNP can ameliorate the intestinal barrier through modulation of the gut microbiota, maintain the blood glucose level, and regulate body weight and the antioxidant function. Although the benefits of LJNP on host health were partly revealed, mechanisms such as the weight loss effect require further study.

Gut Microbial Metabolites and Biochemical Pathways Involved in Irritable Bowel Syndrome: Effects of Diet and Nutrition on the Microbiome

The food we consume and its interactions with the host and their gut microbiota affect normal gut function and health. Functional gut disorders (FGDs), including irritable bowel syndrome (IBS), can result from negative effects of these interactions, leading to a reduced quality of life. Certain foods exacerbate or reduce the severity and prevalence of FGD symptoms. IBS can be used as a model of perturbation from normal gut function with which to study the impact of foods and diets on the severity and symptoms of FGDs and understand how critical processes and biochemical mechanisms contribute to this impact. Analyzing the complex interactions between food, host, and microbial metabolites gives insights into the pathways and processes occurring in the gut which contribute to FGDs. The following review is a critical discussion of the literature regarding metabolic pathways and dietary interventions relevant to FGDs. Many metabolites, for example bile acids, SCFAs, vitamins, amino acids, and neurotransmitters, can be altered by dietary intake, and could be valuable for identifying perturbations in metabolic pathways that distinguish a "normal, healthy" gut from a "dysfunctional, unhealthy" gut. Dietary interventions for reducing symptoms of FGDs are becoming more prevalent, but studies investigating the underlying mechanisms linked to host, microbiome, and metabolite interactions are less common. Therefore, we aim to evaluate the recent literature to assist with further progression of research in this field.