Low FODMAP Research Articles

Does Fibre-fix provided to people with irritable bowel syndrome who are consuming a low FODMAP diet improve their gut health, gut microbiome, sleep and mental health?

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Abstracts Teaching Kitchen Research Conference Los Angeles, California October 18–19, 2022

Abstracts Teaching Kitchen Research Conference Los Angeles, California <i>October 18–19, 2022</i>

I Am the 1 in 10-What Should I Eat? A Research Review of Nutrition in Endometriosis.

Endometriosis is a chronic, painful, estrogen-related inflammatory disease that affects approximately 10% of the female population. Endometriosis has a significant negative impact on quality of life. Nutrition may be involved in the development and severity of endometriosis. The purpose of this paper is to discuss in detail the nutritional recommendations for patients with endometriosis. This article discusses the importance of nutrients such as polyphenols, vitamins C, D and E, PUFAs, and iron in the development of endometriosis. Alternative diets, such as the Mediterranean, anti-inflammatory, vegetarian, low-nickel and low-FODMAP diets, have also been presented in the context of their potential beneficial effects on the course of endometriosis.

A Reduced Tryptophan Diet in Patients with Diarrhoea-Predominant Irritable Bowel Syndrome Improves Their Abdominal Symptoms and Their Quality of Life through Reduction of Serotonin Levels and Its Urinary Metabolites.

(1). An essential component of any treatment for patients with irritable bowel syndrome (IBS) is an adequate diet. Currently, a low FODMAP diet is recommended as a first-line therapy, but it does not relieve abdominal discomfort in all patients, and alternative nutritional treatment is required. The purpose of this study was to evaluate the effect of a tryptophan-lowering diet (TRP) on abdominal and mental symptoms in patients with irritable bowel syndrome with predominant diarrhea (IBS-D). (2). The study included 40 patients with IBS-D, and 40 healthy subjects served as a baseline for IBS-D patients, after excluding comorbidities. The TRP intake was calculated using the nutritional calculator. The severity of abdominal symptoms was assessed using the gastrointestinal symptom rating scale (GSRS-IBS). Mental state was assessed using the Hamilton anxiety rating scale (HAM-A), the Hamilton depression rating scale (HAM-D), and the insomnia severity index (ISI). The serum levels of serotonin and melatonin and the urinary excretion of their metabolites 5-hydroxyindoleacetic acid (5-HIAA) and 6-sulfatoxymelatonin (aMT6) were determined by the ELISA method. The severity of symptoms and laboratory data were analyzed before and after a 12 week diet with tryptophan restricted to a daily dose 10 mg per kilogram body weight. (3). Compared to the control group, patients with IBS-D had a higher serum level of serotonin (198.2 ± 38.1 vs. 142.3 ± 36.4 ng/mL; p < 0.001) but a similar level of melatonin (8.6 ± 1.1 vs. 9.4 ± 3.0 pg/mL; p > 0.05). The urinary excretion of 5-HIAA was also higher in patients with IBS-D patients (7.7 ± 1.5 vs. 6.0 ± 1.7 mg/24 h; p < 0.001). After nutritional treatment, both the serum serotonin level and the urinary 5-HIAA excretion significantly decreased (p < 0.001). The severity of the abdominal symptoms and anxiety also decreased, while the HAM-D score and the ISI score remained unchanged (4). Lowering the dietary intake of tryptophan may reduce abdominal complaints and does not alter the mental state of IBS-D patients.

Gut microbiota in human health: insights and discussion on the role of probiotics

&lt;p&gt;Gut microbiota remains stable and individualized throughout life, but there are inter-species or intra-species variations that may be controlled by various environmental factors. Several diseases may be associated with dysbiosis like inflammatory bowel disease (IBD), obesity, diabetes mellitus, irritable bowel syndrome (IBS), gastric and colon cancer, and sometimes colorectal polyps, non-alcoholic steatohepatitis (NASH), and liver cirrhosis, because of the gut-derived neurotoxins. There is a 10% to 30% risk of development of post-infectious IBS despite the beneficial effects of a low FODMAP diet on IBS symptoms. This diet reduces the luminal concentration of one of the most common bacteria that is the &lt;em&gt;Bifidobacterium&lt;/em&gt;. Therefore, probiotics help in the restoration of normal gut microbiota, are a valuable tool in the treatment of certain diseases and help in recovering microbial balance in the gut. &lt;em&gt;Bifidobacterium&lt;/em&gt; W11 is a novel probiotic with certain special characteristics that can be of benefit in dysbiosis. This review evaluates gut microbiota dysbiosis, associated complications of dysbiosis, and benefits of treatment with probiotics based on focused group discussions of various experts from India, followed by guidance statements based on analysis of published literature. The beneficial effects of &lt;em&gt;Bifidobacterium longum&lt;/em&gt; W11 (&lt;em&gt;B. longum&lt;/em&gt; W11) in the management of IBS, IBD, and liver diseases have been elaborated. The proposed management strategy can effectively aid the management of gut dysbiosis in several gastrointestinal conditions and help in understanding the judicious use of probiotics.&lt;/p&gt;

The low-FODMAP diet and the gluten-free diet in the management of functional abdominal bloating and distension

This review summarizes current knowledge on the role of low-FODMAP diet and gluten-free diet in functional abdominal bloating and distension, an emerging disorder of gut-brain interaction characterized by remarkable costs for healthcare systems and a significant impact on the patient's quality of life. Ingested food plays a key role in the pathophysiology of disorders of gut-brain interaction as up to 84% of patients with irritable bowel syndrome (IBS) report food-triggered symptoms. Potential pathogenetic mechanisms of food-related symptoms in these patients are discussed, focusing on bloating and abdominal distension. These mechanisms provide the rationale for dietary treatment in patients with functional abdominal bloating and distension. The role of fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPs) and gluten in functional abdominal bloating and distension is examined. Current literature evaluating the efficacy of the low-FODMAP diet and the gluten-free diet in abdominal bloating and distension is analyzed. Available evidence originates mainly from studies on patients with IBS, since clinical studies on selected cohorts of patients with only functional abdominal bloating and distension have been missing to date. Promising evidence on the potential efficacy of the low-FODMAP diet in functional abdominal bloating and distension is provided by the reduction of the bloating observed in patients with IBS. Regarding the gluten-free diet, there is insufficient evidence to recommend it to reduce bloating and abdominal distension. In conclusion, this review asserts the need for a close collaboration with experts in nutrition to optimize the management of these patients and reduce the risks associated with elimination diets.

Low FODMAP diet reduces gastrointestinal symptoms in irritable bowel syndrome and clinical response could be predicted by symptom severity: A randomized crossover trial

Fermentable oligo-, di-, monosaccharides and polyols (FODMAPs) can provoke symptoms in patients with irritable bowel syndrome (IBS). We aimed to compare the effects of diets with low vs. moderate FODMAP content on gastrointestinal (GI) symptoms and bowel habits, and to identify possible predictors of clinical response to a low FODMAP diet and FODMAP sensitivity in IBS. Adult participants with IBS (Rome IV criteria, n=29) were included and adhered to two 7-day diet periods, with either low (4 g/day) or moderate (23 g/day) amounts of FODMAPs, in this randomized, double-blind, crossover study. The periods were separated by a wash-out period (≥14 days). IBS-Severity Scoring System (IBS-SSS) and a stool diary (Bristol Stool Form) were completed before and after the diet periods. At baseline, severity of GI symptoms and gut microbial fermentation were assessed (every 15 min, 4 h) during the Lactulose Nutrient Challenge Test (LNCT). Clinical response and FODMAP sensitivity were defined by reduction after low FODMAP period, and increase after moderate FODMAP period in IBS-SSS (≥50 points), respectively. Severity of GI symptoms (P=0.04), stool consistency (P=0.01), and stool frequency (P=0.01) differed between the interventions, with reduced overall GI symptom severity, abdominal pain intensity and frequency, bowel habits dissatisfaction, and daily life interference (P<0.05 for all), as well as more firm (P=0.03) and less frequent (P<0.01) stools after low FODMAP intervention, but not after moderate FODMAP intervention. A third (34%) responded clinically to the low FODMAP diet, and the response could be predicted by higher IBS-SSS at baseline (P=0.02). Although modest associations between FODMAP sensitivity (22%) and GI symptoms during LNCT were observed, no independent predictors could be identified. A diet low in FODMAPs reduces GI symptoms and affects bowel habits in IBS, compared with a moderate FODMAP diet. Assessment of IBS severity before the intervention may be used to predict clinical response to a low FODMAP diet. Trial registry (http://www. gov): Registered under Clinical Trial number NCT05182593.

Effectiveness of the low-FODMAP diet in improving non-celiac gluten sensitivity: a systematic review.

Non-celiac gluten sensitivity is characterised by the presence of gastrointestinal and extraintestinal symptoms following gluten ingestion. Recent studies suggested an association between non-celiac gluten sensitivity and the consumption of fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAP). This systematic review aimed to examine literature evidence on the relationship between non-celiac gluten sensitivity and FODMAP intake. A comprehensive search was carried out for randomised clinical trials addressing gastrointestinal symptoms as the primary outcome, published between 2010 and 2020 in Portuguese, English or Spanish, and indexed in Scopus, PubMed, SciELO, Cochrane Library, CINAHL, Embase or VHL (LILACS) databases. The systematic review was performed using the population, intervention, comparison and outcome (PICO) framework. A total of 1133 articles were retrieved for further assessment. Three articles were selected for systematic review, one of which included two interventions with different periods and assessments. Quality of evidence was assessed according to the GRADE protocol. The selected articles used different instruments to measure gastrointestinal symptoms and quality of life, hindering comparison of data. Clinical trials identified an association between decreased gastrointestinal symptoms and FODMAP restriction. There are few studies on the topic, and those available used different instruments to assess gastrointestinal symptoms and quality of life. Nevertheless, current evidence supports the gluten-free diet still represents first-line therapy. However, a FODMAP restriction can decrease gastrointestinal symptoms in individuals with non-celiac gluten sensitivity. Further research is needed to confirm this finding.

Evaluation of the Effects of the Tritordeum-Based Diet Compared to the Low-FODMAPs Diet on the Fecal Metabolome of IBS-D Patients: A Preliminary Investigation.

Since irritable bowel syndrome (IBS)-a common gastrointestinal (GI) disorder-still lacks effective therapy, a nutritional approach may represent a practical alternative. Different reports demonstrated that a low-fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAPs) diet (LFD) reduces symptoms in IBS with diarrhea (IBS-D) patients, also inducing beneficial pathophysiological and biochemical modifications. More recently, diets with alternative cereals having a different gluten composition, such as tritordeum, have also been considered (TBD). We investigated the impact of TBD and LFD on the fecal metabolome composition in 38 IBS-D patients randomly allocated to the two diets for 12 weeks. Summarily, at baseline, the profile of fecal volatile organic compounds (VOCs) of IBS-D patients was not significantly different in the two groups. After treatment, significant changes were observed in the two groups regarding the VOCs content since some of them increased in the TBD group (namely, decanoic acid), whereas others (i.e., nonanal and ethanol) increased in the LFD one. Further, at baseline, short-chain fatty acids were positively related to inflammation and showed a significant decreasing trend after both diets compared to baseline values (namely, acetic and propanoic acid). Preliminary results from this pilot study suggest a potential positive intervention of TBD and LFD affecting the fecal metabolome composition in IBS-D patients.

Diet-induced modifications to human microbiome reshape colonic homeostasis in irritable bowel syndrome.

Changes in microbiome composition are associated with a wide array of human diseases, turning the human microbiota into an attractive target for therapeutic intervention. Yet, clinical translation of these findings requires the establishment of causative connections between specific microbial taxa and their functional impact on host tissues. Here, we infuse gut organ cultures with longitudinal microbiota samples collected from therapy-naive patients with irritable bowel syndrome (IBS) under a low-fermentable oligo-, di-, mono-saccharides and polyols (FODMAP) diet. We show that post-diet microbiota regulates intestinal expression of inflammatory and neuro-muscular gene sets. Specifically, we identify Bifidobacterium adolescentis as a diet-sensitive pathobiont that alters tight junction integrity and disrupts gut barrier functions. Collectively, we present a pathway discovery platform for mechanistic dissection and identification of functional diet-host-microbiota modules. Our data support the hypothesis that the gut microbiota mediates the beneficial effects of a low-FODMAP diet and reinforce the potential feasibility of microbiome-based therapies in IBS.

Low-FODMAP Diet for the Management of Irritable Bowel Syndrome in Remission of IBD.

Approximately 30% of patients with quiescent inflammatory bowel disease (IBD) meet the diagnostic criteria for irritable bowel syndrome (IBS). The aim of this study was to evaluate the effectiveness of a low-FODMAP diet in patients who meet the diagnostic criteria for IBS whilst in IBD remission. A total of 200 patients in remission of IBD were included in the study. Sixty-five of these patients (32.5%) were diagnosed with IBS according to the R4DQ. On the patients who met the IBS diagnostic criteria, anthropometric measurements, laboratory tests and lactulose hydrogen breath tests were performed. A low-FODMAP diet was introduced for 6 weeks. Of the 59 patients with IBS diagnosed at baseline for whom data were collected at the end of follow-up, after the low-FODMAP intervention IBS-like symptoms were not present in 66.1% (n = 39) (95% CI (53.4%; 76.9%)). The difference between the two groups (with SIBO at baseline (33 of 48 patients) and without SIBO at baseline (6 of 11 patients)) in the low-FODMAP diet's effectiveness was not statistically significant (p = 0.586). The low-FODMAP diet improved the gut symptoms of flatulence and diarrhea. It had no effect on the occurrence of constipation. In IBD patients in remission who meet the IBS criteria, the dietary intervention of a low-FODMAP diet is effective for a reduction in IBS-like symptoms, regardless of the coexistence of bacterial overgrowth.

Fecal microbiota transplantation in patients with post-infectious irritable bowel syndrome: A randomized, clinical trial

Research in recent years has shown the potential benefits of fecal microbiota transplantation (FMT) for irritable bowel syndrome (IBS). Acute infectious gastroenteritis is a well-established risk factor for developing such forms of IBS as post-infectious IBS (PI-IBS). However, the effective use of FMT in patients with IP-IBS has not yet been clarified. The study aimed to conduct a single-center, randomized clinical trial (RCT) to assess FMT's safety, clinical and microbiological efficacy in patients with PI-IBS. Patients with PI-IBS were randomized into two groups: I (standard-care, n = 29) were prescribed basic therapy, namely a low FODMAP diet, as well as Otilonium Bromide (1 tablet TID) and a multi-strain probiotic (1 capsule BID) for 1 month; II (FMT group, n = 30), each patient with PI-IBS underwent a single FMT procedure with fresh material by colonoscopy. All patients underwent bacteriological examination of feces for quantitative and qualitative microbiota composition changes. The clinical efficacy of treatment was evaluated according to the dynamics of abdominal symptoms, measured using the IBS-SSS scale, fatigue reduction (FAS scale), and a change in the quality of life (IBS-QoL scale). FMT was associated with rapid onset of the effect, manifested in a significant difference between IBS-SSS points after 2 weeks of intervention (p < 0.001). In other time points (after 4 and 12 weeks) IBS-SSS did not differ significantly across both groups. Only after 3 months of treatment did their QoL exceed its initial level, as well value for 2 and 4 weeks, to a significant extent. The change in the ratio of the main microbial phenotypes in the form of an increase in the relative abundance of Firmicutes and Bacteroidetes was recorded in all patients after 4 weeks. It should be noted that these changes were significant but eventually normalized only in the group of PI-IBS patients who underwent FMT. No serious adverse reactions were noted. This comparative study of the results of FMT use in patients with PI-IBS demonstrated its effectiveness compared to traditional pharmacotherapy, as well as a high degree of safety and good tolerability.

Diagnostic management of patients reporting symptoms after wheat ingestion.

Many patients report symptoms after wheat ingestion experiencing a wide spectrum of clinical manifestations. Three possible diagnoses have been recognized: celiac disease (CD), wheat allergy (WA), and non-celiac (gluten) wheat sensitivity (NCGS/NCWS). CD is a chronic immune-mediated disease of the small bowel caused by exposure to dietary gluten in genetically predisposed individuals, with a prevalence of approximately 1%. It is characterized by mucosal inflammation and atrophy following exposure to gluten and improvement after gluten withdrawal. Food allergies are immunological responses to a food antigen. WA is the expression of an immunologically mediated process that can be immunoglobulin E (IgE) or non-IgE mediated; its many symptoms include urticaria/angioedema, asthma, rhinitis, and anaphylaxis. NCGS/NCWS is characterized by gastrointestinal and/or extra-intestinal symptoms after ingestion of gluten-containing food in subjects not affected by CD or WA. The aim of this review is to help physicians and nutritionists diagnose the cause of symptoms reported after wheat ingestion, thus avoiding patient frustration, inappropriate testing, and incorrect or missed diagnoses. An algorithm for the diagnostic approach in these patients is provided, to help to diagnose CD, WA, NCGS/NCWS or to identify possible functional disorders as the wheat-sensitive irritable bowel syndrome. A personalized approach, regular follow-up, and the help of a skilled healthcare professional are mandatory for patients with symptoms following wheat ingestion is provided. A gluten-free-diet is often recommended for patients with self-reported gluten/wheat-dependent symptoms; for patients with symptoms similar to those of functional diseases while there is evidence that a low-FODMAP diet could be the first option.

Traditional, Vegetarian, or Low FODMAP Diets and Their Relation to Symptoms of Eating Disorders: A Cross-Sectional Study among Young Women in Poland.

Background: Eating disorders (EDs) are an ever-growing problem, seen most commonly among young women. People with EDs are particularly predisposed to restrictive eating patterns. Diet therapy for many diseases involves the elimination of certain food groups, and the use of restrictive diets in people with EDs may indirectly influence the recurrence of the disorder. The aim of this study was to assess the prevalence of the possible presence of EDs and orthorexia symptoms among young women following a traditional, alternative (vegetarian), or therapeutic (low FODMAP) diet. Methods: The analysis was based on 420 responses from female respondents aged 19 to 30 years. The research tool consisted of questionnaires to assess the possible presence of EDs (SCOFF), cognitive-behavioral aspects of eating (TFEQ-13), and the presence of orthorexia symptoms (ORTO-15). Results: Uncontrolled and emotional eating was least common in women on a vegetarian diet (5.6 ± 3.7; 3.5 ± 2.7; p < 0.05). Women on a low FODMAP diet were most prevalent with symptoms of orthorexia (n = 37, 47.4%; p < 0.05). Conclusions: It seems important to perform screening tests for eating disorders before recommending diet therapy in order to individually adjust the dietary regimen and refer patients to appropriate specialists.

Inflammatory Bowel Disease and Customized Nutritional Intervention Focusing on Gut Microbiome Balance.

Inflammatory bowel disease (IBD) represents a chronic relapsing–remitting condition affecting the gastrointestinal system. The specific triggering IBD elements remain unknown: genetic variability, environmental factors, and alterations in the host immune system seem to be involved. An unbalanced diet and subsequent gut dysbiosis are risk factors, too. This review focuses on the description of the impact of pro- and anti-inflammatory food components on IBD, the role of different selected regimes (such as Crohn’s Disease Exclusion Diet, Immunoglobulin Exclusion Diet, Specific Carbohydrate Diet, LOFFLEX Diet, Low FODMAPs Diet, Mediterranean Diet) in the IBD management, and their effects on the gut microbiota (GM) composition and balance. The purpose is to investigate the potential positive action on IBD inflammation, which is associated with the exclusion or addition of certain foods or nutrients, to more consciously customize the nutritional intervention, taking also into account GM fluctuations during both disease flare-up and remission.

S529 Do Social Determinants of Health Impact Which Patients Are Referred for the Low FODMAP Diet?

Introduction: The aim of this study was to explore if differences in social determinants of health in irritable bowel syndrome (IBS) patients impact access to the low FODMAP diet (LFD). Methods: A prospective cross-sectional survey of 486 adults was performed from May – June 2022. All respondents completed a 31-question survey via Survey Monkey. The survey link was distributed via social media platforms, low FODMAP dietician blog posts, and the IFFGD newsletter. Questions consisted of social determinants, such as the number of family members in their home, education attainment, employment status, healthcare insurance, access to healthcare, housing, utilities, transportation, childcare, and food access and insecurities. Statistical analyses included the Mann-Whitney U test and chi-square test. A p-value of ≤ 0.05 was considered statistically significant. Results: 462/486 (95.1%) respondents reported a diagnosis of IBS. Patients without a diagnosis of IBS were removed from the analysis. IBS cohort demographics consisted of 93% female, 92.5% Caucasian, and 92.7% residing in the United States. The primary IBS complaint was equally distributed: IBS-Diarrhea (35.1%), IBS-Constipation (29.1%), and IBS-Mixed (35.1%). 83.6% (n = 400) of IBS respondents were recommended the low FODMAP diet for treatment of their GI symptoms by a medical provider. IBS respondents were divided into two groups: IBS-LFD+ (n = 400, those referred for low FODMAP diet education) and IBS-LFD- (n = 62, those not referred for low FODMAP diet education). Compared with their IBS-LFD+, IBS-LFD- respondents had a lower education level (14.8% with high school diploma or less vs. 5.8%, p =0.01), lower household income (46.7% with income ≤ $74,999 vs. 30.7%, p =0.03), and decreased access food when needed (8.1 vs. 2.8 %, p = 0.03). IBS-LFD- respondents were also less likely start a low FODMAP diet on their own compared to IBS-LFD+ counterparts (12.4% vs. 87.6%, p < 0.001). Conclusion: IBS patients with a lower socioeconomic position were less likely to be recommended the low FODMAP diet as treatment compared to patients with higher socioeconomic positioning. This raises concern socioeconomic status negatively impacts referral for low FODMAP diet for IBS management and suggests implicit referral bias. Given the increasing evidence for dietary therapy for managing GI symptoms, further investigation is needed to identify how provider perceptions of patients influence dietary treatment recommendations. Table 1. - Comparison of social determinants between IBS patients recommended vs. NOT recommended the low FODMAP diet by their health provider Social Determinant Variable IBS patients recommended low FODMAP Diet [IBS-LFD+](n = 400) IBS patients NOT recommended low FODMAP Diet[IBS-LFD-](n = 62) P-Value Cramer V Coefficient Odds Ratio (OR) 95% Confidence Interval (CI) Highest Level of Education Attainment High school diploma/ GED or less 5.8% 14.8% 0.01 0.12 2.31 1.26, 4.25 ≥ High School Diploma/GED 94.2% 85.2% Household Income $0.00 - $74,999 30.7% 46.7% 0.03 0.11 1.81 1.05, 3.11 ≥ $75,000 69.3% 53.3% Access to Food When Needed Unable to access food when needed 2.8% 8.1% 0.03 0.10 2.45 1.14, 5.26 Likely to start low FODMAP diet on their own Yes 87.6% 12.4% < 0.001 0.19 0.28 0.16, 0.50 No 56.6% 44.4% Visit a registered dietitian about the low FODMAP diet Yes 88.2% 11.8% 0.06 0.09 0.64 0.40, 1.03 No 81.6% 18.4%

Effects of a low FODMAP diet on the colonic microbiome in irritable bowel syndrome: a systematic review with meta-analysis

ABSTRACTBackgroundA low fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAP) diet is increasingly used to manage symptoms in irritable bowel syndrome (IBS). Although this approach may alter the colonic microbiome, the nature of these changes has not been comprehensively synthesized.ObjectivesThe aim of this study was to conduct a systematic review with meta-analysis of randomized controlled trials examining the impact of a low FODMAP diet on the composition and function of the microbiome in patients with IBS.MethodsA systematic search was conducted for randomized controlled trials evaluating the effects of a low FODMAP diet on the colonic microbiome in patients with IBS in MEDLINE, EMBASE, CENTRAL, and Web of Science from inception to April 2022. Outcomes included diversity of the microbiome, specific bacterial abundances, fecal SCFA concentration, and fecal pH. For fecal SCFA concentrations and pH, meta-analyses were performed via a random-effects model.ResultsNine trials involving 403 patients were included. There were no clear effects of the low FODMAP diet on diversity of the microbiome. A low FODMAP diet consistently led to lower abundance of Bifidobacteria, but there were no clear effects on diversity of the microbiome or abundances of other specific taxa. There were no differences in total fecal SCFA concentration between the low FODMAP diet and control diets (standardized mean difference: −0.25; 95% CI: −0.63, 0.13; P = 0.20), nor were there differences for fecal concentrations of specific SCFAs or fecal pH.ConclusionsIn patients with IBS, the effects of a low FODMAP diet on the colonic microbiome appear to be specific to Bifidobacteria with no consistent impacts on other microbiome metrics, including diversity, fecal SCFA concentrations, and fecal pH. Further, adequately powered trials are needed to confirm these findings.This review was registered at https://www.crd.york.ac.uk/prospero/ as CRD42020192243.

S525 The Low FODMAP Diet Improves Abdominal and Overall Symptoms in Patients With All Subtypes of Irritable Bowel Syndrome

Introduction: There is substantial evidence that a diet low in fermenTable oligo-, di-, monosaccharides, and polyols (FODMAPs) improves symptoms in patients with Irritable Bowel Syndrome and diarrhea (IBS-D). Though the low-FODMAP diet is increasingly used in patients with IBS and constipation (IBS-C) or mixed bowel habits (IBS-M), there is little data to support this practice. We aim to compare the real-world effectiveness of a low-FODMAP diet in patients with IBS-D, IBS-C, and IBS-M. Methods: Utilizing a commercially available meal procurement service which prepares and delivers meals certified low in FODMAP content (Modify Health, Atlanta, GA), patients with suspected IBS met with a registered dietitian and completed the IBS symptom severity scale (IBS-SSS) questionnaire before starting the low-FODMAP diet and after the restriction phase of the diet plan. A decrease in IBS-SSS score of >100 was defined as a responder. Results: 403 IBS patients filled out baseline and post-elimination IBS-SSS surveys. 26% of patients were referred by a GI specialist; the rest were self-referrals. 193 (48%) patients had severe IBS (IBS-SSS > 300) prior to the intervention. IBS-D patients had a 71% improvement in pain, 56% improvement in bloating, and 55% improvement in bowel movement satisfaction. 77% of IBS-D patients had improvement in total IBS-SSS >100. IBS-C patients had a 69% improvement in pain, 49% improvement in bloating, and 42% improvement in bowel movement satisfaction. 67% of IBS-C patients had improvements in IBS-SSS >100. IBS-M patients had 85% improvement in pain, 55% improvement in bloating, and 53% improvement in bowel movement satisfaction. 72% of IBS-M patients had improvement in total IBS-SSS >100. Those who used the commercial meals for "all" of the restriction phase had a mean IBS-SSS improvement of 174, and mean quality of life (QOL) improvement of 40%, while those who used the commercial meals for "some" of the elimination phase had mean IBS-SSS improvement of 153, and mean QOL improvement of 33% (p=0.059 and 0.03, respectively). (Table) Conclusion: This data supports the effectiveness of a low-FODMAP diet for all IBS subtypes, including IBS-C and IBS-M. Patients who obtained prepared low-FODMAP meals during the entire restriction phase experienced greater benefits than those who only obtained meals for a portion of the restriction phase. Table 1. - Improvement in IBS-SSS Categories by IBS-Subtype IBS Subtype Total Number of Patients IBS-SSS (Mean % Improvement) Pain (Mean % Improvement) Bloating (Mean % Improvement) BM Satisfaction (Mean % Improvement) % Improvement in IBS-SSS >100 IBS-D 87 59 (p< 0.001) 72 56 56 77 IBS-C 73 50 (p< 0.001) 70 49 42 67 IBS-M 91 56 (p< 0.001) 73 55 53 73

Fecal Microbiota Transplantation Combined with a Low FODMAP Diet for the Treatment of Irritable Bowel Syndrome with Predominant Diarrhea.

Background Fecal microbiota transplantation (FMT) has been found to be effective in irritable bowel syndrome with predominant diarrhea (IBS-D). We conducted this study to determine the impact of a low FODMAP diet (LFD) on the gut microbiota and the efficacy of FMT in the treatment of IBS-D. Methods A retrospective analysis of a single-arm open-label prospective study was conducted to investigate the impact of FMT alone (n = 40) and FMT+LFD (n = 40) in refractory IBS-D. The IBS-quality of life (QOL), IBS-severity scoring system (SSS), gastrointestinal symptom rating scale (GSRS), Hamilton anxiety scale (HAMA), and Hamilton depression scale (HAMD) were used to evaluate the efficacy, and partial 16S rDNA amplicon sequencing was used to profile the microbiota. Results The response rates were higher in the FMT+LFD group than in the FMT group (1 mo, 3 mo, 6 mo: 70.0% vs. 55.0%, 67.5% vs. 57.5%, 62.5% vs. 27.5%, respectively). The FMT+LFD group showed significantly better improvement in IBS-QOL at 1, 3, and 6 months; IBS-SSS at 6 months; and GSRS at 1 month compared to FMT alone. Changes in HAMA and HAMD were similar in the two groups. The LFD significantly upregulated the FMT-induced microbial diversity (OTUs: 666 vs. 574, Adonis: P = 0.02) and significantly strengthened the upregulation of Bacteroides, Alistipes, and Ruminococcaceae_UCG-002 and the downregulation of Bifidobacterium. Conclusion An LFD enhanced the efficacy of FMT, increased the gut microbial diversity after FMT, and strengthened the inhibitory effect of FMT on conditional pathogens.

Irritable bowel syndrome - pathophysiology, diagnosis, treatment. The role of low FODMAP diet

Introduction: The gut microbiota is the microorganisms in the digestive tract. They are mainly bacteria. They play a very important role in maintaining the body's homeostasis. The state of the microbiota is influenced by lifestyle including diet, stress and physical activity. In irritable bowel syndrome, there are disorders in the composition of the intestinal microbiota. It is also associated with a disruption in the proper functioning of the gut-brain axis. Aim: The aim of this study was to review the literature reports on irritable bowel syndrome and the impact of a low FODMAP diet. Methods: Data for the article were retrieved using PubMed setting the time descriptors to 2017-2021. Results and conclusions: Irritable bowel syndrome (IBS) is a chronic functional gastrointestinal disease. It is manifested by chronic abdominal pain , diarrhea or constipation and changes in the frequency of bowel movements. It significantly affects the quality of life of patients. The diagnosis uses the Roman IV criteria. Pharmacological as well as non-pharmacological methods are important in the treatment. A low-FODMAP diet plays a major role. Studies show that its proper use significantly alleviates the symptoms of IBS.