Low FODMAP Research Articles

Response of Irritable Bowel Syndrome to Abdominal Fat Reduction

Objectives: The study aimed to evaluate the response of Irritable Bowel Syndrome (IBS) among patients having central obesity to reducing abdominal fat using Focused Ultrasound (cavitation) in addition with aerobic exercise as well as a low calorie, low-FODMAPs diet. Methods: A total of 60 individuals, between the ages of 20 and 45, who were diagnosed with both irritable bowel syndrome (IBS) as well as abdominal obesity, having a body mass index (BMI) ranging from 30 to 39.9 kg/m², were divided into two groups of similar size by a random assignment process. Group A were given focused ultrasound cavitation accompanied by moderate aerobic exercise and a low calorie, low-FODMAPs diet over a period of three months, whereas Group B (control group) were given moderate aerobic exercise and a low calorie, low-FODMAPs diet only. Assessments of total body fat, abdominal fat, severity of IBS, as well as quality of life related to IBS were conducted prior to and after the study period. Results: Overall body fat mass, abdominal fat mass, IBS severity, and IBS quality of life were all significantly improved in both groups. All evaluated variables showed a highly significant improvement in favor of the study group when comparing the two groups. Conclusion: Focused Ultrasound (cavitation) in addition with aerobic exercise as well as a low calorie, low-FODMAPs diet cause more improvement of irritable bowel syndrome symptoms and quality of life.

Use of Carbohydrate (CHO), Gluten-Free, and FODMAP-Free Diets to Prevent Gastrointestinal Symptoms in Endurance Athletes: A Systematic Review

Background: Gastrointestinal symptoms (GISs) can affect the performance of endurance athletes (EAs). This study aims to analyze the efficacy of carbohydrate (CHO), gluten-free, and low-mono-saccharide and polyol (FODMAP) diets in preventing GISs in adult EAs of both sexes. Methods: A systematic search was conducted prior to 30 June 2024 in accordance with the PRISMA statement. We searched for original studies from the last eight years, in English or Spanish, that looked at the effect of CHO, gluten-free, or FODMAP diets on the GISs of EAs. In PubMed, the MeSH (medical subject heading) categories were used. The search was repeated in EBSCO, Google Scholar, and Web of Science. The inclusion criteria were determined using the PICOS framework and the risk of bias in each paper was assessed using the PEDro scale quality criteria checklist (systematic review registration: INPLASY202490080). Results: Of 289 articles identified, only 3.5% met the eligibility criteria. All studies found that GISs are common in EAs. We found that 60% of the articles used an experimental method; moreover, based on 80% of the articles, following a bowel training diet, like CHO, reduced fiber and dairy products, or a low-FODMAP diet, has the potential to reduce gastrointestinal symptoms and improve the athletic performance of EA. Conclusions: We found that low-FODMAP diets, gut training with CHO intake, and decreased fiber and dairy intake may have favorable effects in preventing GISs. No studies support a gluten-free diet in reducing GISs in EAs.

A service evaluation of FODMAP restriction, FODMAP reintroduction and long-term follow-up in the dietary management of irritable bowel syndrome.

The dietary restriction of fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAPs), called the low-FODMAP diet (LFD), is frequently used to manage irritable bowel syndrome (IBS). This service evaluation aimed to assess the long-term effectiveness of the LFD in managing IBS symptoms and whether symptom response and dietary adherence to the LFD were associated. This observational service evaluation collected data via questionnaires during clinical dietetic appointments for IBS management. Symptom severity was reported at baseline, short term (following FODMAP restriction) and long term (following FODMAP reintroduction). Additional data that captured experiences following the LFD were collected at long-term follow-up. Of 184 patients, 14% reported satisfactory relief from global symptoms at baseline, which increased to 69% at short-term follow-up and 57% at long-term follow-up (p < 0.001). The most notable improvements in individual symptoms between baseline and long-term follow-up were abdominal bloating (72% baseline, 48% long term, p < 0.001), abdominal pain (61% baseline, 30% long term, p < 0.001) and flatulence (71% baseline, 40% long term, p < 0.001). High adherence with the LFD at short-term follow-up was not associated with long-term symptom improvement, but there was an association between long-term adherence and global symptom severity (p = 0.032). Completion of FODMAP reintroduction as per protocol was associated with long-term symptom improvement (p = 0.049). The LFD is an effective treatment for managing IBS symptoms in the long term, particularly, when the diet is adhered to and reintroduction is completed as per dietetic education. Further randomised-controlled trials are required to explore the cause-and-effect relationship between LFD and IBS symptom management.

Positive Outcomes of Supplementation with Lecithin-Based Delivery Formulation of Curcuma longa and Boswellia serrata in IBS Subjects with Small Bowel Dysbiosis

Background: Small bowel dysbiosis (SBD) is a frequent finding in subjects with irritable bowel syndrome (IBS). The sunflower lecithin (phytosome) formulation of Curcuma longa and Boswellia serrata demonstrated beneficial effects on intestinal microbiota. This study aimed to evaluate the impact of a lecithin-based delivery formulation of Curcuma longa and Boswellia serrata extracts (CUBO) on SBD in IBS subjects. Subjects: Forty-nine adult subjects with IBS and SBD were randomly supplemented for 30 days with CUBO and a low-FODMAP diet (LFD) (intervention) or with LFD and placebo (control group). Results: The intervention group showed a significant reduction in urinary indican (p &lt; 0.001), which was the marker of SBD, and of abdominal bloating (p &lt; 0.001) and abdominal pain (p &lt; 0.001). The pre–post control group analysis did not evidence significant differences. The comparison between the two groups (net effect in intervention minus control subjects) showed that the changes differ significantly for urinary indican p &lt; 0.001 (−42.88; 95% CI: −62.04 to −23.72), abdominal bloating p &lt; 0.001 (−1.50; 95% CI: −1.93 to −1.07), and abdominal pain p &lt; 0.001 (−2.37; 95% CI: −3.61 to −1.13) and for the global assessment of efficacy (p &lt; 0.001). The efficacy was 20% greater in males than in females. Conclusions: In IBS subjects, the intervention with CUBO and LFD shows a significantly higher reduction in SBD, abdominal pain, and bloating compared to LFD and placebo. Additional research is needed to confirm these data.

Practices and Barriers in Implementing the Low FODMAP Diet for Irritable Bowel Syndrome Among Malaysian Dietitians: A Qualitative Study.

The low fermentable oligo-, di-, mono-saccharides and polyols (FODMAP) diet (LFD) is a second-line dietary intervention for irritable bowel syndrome (IBS) patients, involving FODMAP restriction, reintroduction, and personalization, and it needs to be delivered by dietitians. However, the application of this diet among Malaysian IBS patients is not well understood. This study aimed to explore the practices and barriers in delivering the LFD among Malaysia dietitians. Semi-structured qualitative interviews were conducted online with practicing dietitians until the data reached saturation. All the interview sessions were audio recorded and transcribed verbatim. Thematic analysis was used to analyze the data. Eleven dietitians were interviewed, with 36.4% (n = 4) having more than 10 years of experience. The following four themes regarding their practices emerged: 1. dietary advice on FODMAP restriction; 2. duration of FODMAP restriction phase; 3. references used to get information about FODMAPs, and 4. strategies on reintroduction. Meanwhile, the following seven barriers were identified: 1. lack of culturally relevant educational materials; 2. limited knowledge about the LFD; 3. inadequate formal training among dietitians; 4. lack of integration in multi-disciplinary care; 5. low health literacy of patients; 6. low compliance rate among patients, and 7. restrictions for certain populations. LFD implementation in Malaysia is not standardized as only experienced dietitians can provide dietary evidence-based advice. Lack of training and culturally specific resources are some of the main barriers that were identified to be limiting the implementation of the diet. Therefore, there is a need for training programs and resource development to support Malaysian dietitians in managing IBS patients.

Gut-Brain Axis and Psychopathology: Exploring the Impact of Diet with a Focus on the Low-FODMAP Approach.

The gut-brain axis (GBA) is a bidirectional communication network connecting the central nervous system with the gastrointestinal (GI) tract, influencing both mental and physical health. Recent research has underscored the significant role of diet in modulating this axis, with attention to how specific dietary patterns can impact anxiety and depression, particularly when linked to disorders of gut-brain interaction (DGBIs), like intestinal bowel syndrome (IBS). This narrative review examines the effects of specific diet regimens on the GBA and its potential role in managing psychopathology, focusing on anxiety and depression, IBS, and the low-FODMAP diet. We conducted a search on PubMed and MEDLINE by combining the following key terms: "Gut-Brain Axis", "Irritable Bowel Syndrome", "Low FODMAP diet", "Mediterranean Diet", "Psychopathology", "Anxiety and Depression", and "Gut Microbiota". We applied the following filters: "Clinical Trials", "Randomized Controlled Trials", "Reviews", "Meta-Analyses", and "Systematic Reviews". In total, 59 papers were included. Low-FODMAP diet, originally developed to alleviate GI symptoms in IBS, may also positively influence mental health by modulating the GBA and improving the gut microbiota (GM) composition. New insights suggest that combining the low-FODMAP diet with the Mediterranean diet could offer a synergistic effect, enhancing both GI and psychological therapeutic outcomes. Understanding the complex interactions between diet, the GM, and mental health opens new avenues for holistic approaches to managing psychopathology, particularly when linked to GI symptoms.

Efficacy and Safety of a Low-FODMAP Diet in Combination with a Gluten-Free Diet for Adult Irritable Bowel Syndrome: A Systematic Review and Meta-Analysis.

Common gastrointestinal disease irritable bowel syndrome (IBS) is marked by symptoms like changed bowel habits, bloating, and stomach ache. A low-FODMAP combined gluten-free diet (LF-GFD) has been suggested as a possible therapy for IBS symptoms management. This study sought to investigate whether a LF-GFD would help patients with IBS. Strict inclusion and exclusion criteria from internet databases helped to identify clinical studies evaluating the intervention of LF-GFD in the treatment of IBS patients. Using measurements including the visual analog scale (VAS) for bloating and pain, the IBS symptom severity scale (IBS-SSS), and IBS quality of life (IBS-QoL), the main results evaluated were the efficacy of LF-GFD in reducing IBS symptoms. Furthermore assessed were the psychological impacts of LF-GFD utilizing the self- rating depression scale (SDS) and self- rating anxiety scale (SAS). A total of 437 patients (221 on LF-GFD diet and 216 on GFD) were involved in 4 randomized controlled trials and 4 cohort studies. The combined results indicated that LF-GFD reduced the VAS bloating ratings (RR = -0.58, 95%CI -0.92-0.23, P = 0.0010, I2 = 83%) and the VAS pain scores (RR = -0.42, 95%CI -0.66-0.19, P = 0.005, I2 = 58%). In addition, LF-GFD indicated a substantial enhancement in IBS-SSS scores (MD = -1.42, 95%CI -2.74-0.10, P = 0.03, I2 = 24%) and IBS-QoL ratings (MD = 3.75, 95%CI 0.98-6.53, P = 0.008, I2 = 33%). Moreover, the LF-GFD group showed a substantial drop in SDS (MD = -2.56, 95%CI -3.38-1.74, P < 0.00001, I2 = 65%) and SAS (MD = -4.30, 95%CI -6.53-2.24, P < 0.0001, I2 = 0%) scores compared to the GFD group. LF-GFD therapy significantly enhances clinical symptoms and reduces anxiety and depression in individuals diagnosed with irritable bowel syndrome.

"Efficacy of the Low-Fodmap Diet in Managing Irritable Bowel Syndrome Symptoms: A Prospective Observational Study at Baghdad Teaching Hospital"

"Efficacy of the Low-Fodmap Diet in Managing Irritable Bowel Syndrome Symptoms: A Prospective Observational Study at Baghdad Teaching Hospital"

Adapted Low-FODMAP Diet in IBS Patients with and without Fibromyalgia: Long-Term Adherence and Outcomes.

A low-FODMAPs Diet (LFD) is considered a "second line" dietary strategy for irritable bowel syndrome (IBS) but, after a period of strict restriction of all FODMAP foods, it has to be adapted and tailored to each patient (AdLFD). Fibromyalgia often coexists with IBS in up to 65% of cases. Our aims were to evaluate if comorbid fibromyalgia influenced the long-term clinical outcomes and adherence to an AdLFD in IBS patients. IBS patients with or without fibromyalgia who had started an AdLFD were enrolled. Patients had been evaluated before starting the LFD (T0). After a mean follow-up of 62.5 ± 22.7 months (T1), they were re-evaluated using questionnaires on disease severity, bowel habits, psychological status, and adherence to AdLFD. In total, 51 IBS patients entered the study. Nineteen of them had comorbid fibromyalgia. Thirty patients reported a reduction in symptom severity at T1 in comparison with T0. Despite some slight differences in single IBS Symptom Severity Score items, comorbid fibromyalgia did not influence the IBS-SSS total score at T1. Patients with comorbid fibromyalgia showed a higher Hospital Anxiety and Depression Scale (HADS) score at baseline. A total of 44 patients showed good long-term adherence to the AdLFD. All patients improved their HADS score and had long-term adherence to the AdLFD. Comorbid fibromyalgia showed only a slight influence on long-term outcomes of an AdLFD on IBS symptoms, without affecting the relief of global symptoms. No influence on long-term adherence to AdLFD was detected. Hence, this approach can be taken into account in fibromyalgia patients for a nonpharmacological management of IBS symptoms. However, multicentric studies on larger samples would be welcome in the future.

Orange Cookies with Type-4 Resistant Starch: Physical, Nutritional, and Sensorial Characteristics as Evaluated by Patients with Irritable Bowel Syndrome

A low-fermentable oligo-, di-, monosaccharide and polyol (low-FODMAP) diet for patients with irritable bowel syndrome (IBS) should include an adequate fiber source. Our aim was to formulate orange cookies using maize flour and type-4 resistant starch (RS4) from maize and to evaluate their properties and sensorial attributes by IBS patients. We prepared two formulations: 37.7% RS4 and 14.7% maize flour and a control with normal maize starch (MS) instead of RS4. We added orange juice and zest instead of water and evaluated their properties. The viscosity, water absorption capacity, and solubility were lower for RS4 than for MS. The width, thickness, L* and a* values of both cookies were comparable (p &gt; 0.05), although RS4-C had a decreased b* value and higher hardness (90.6 vs. 80.1 N). The nutrient content was similar between RS4-C and MS-C, but the glycemic index of RS4-C was 63 compared to 95 of MS-C. According to IBS patients, the appearance, taste, hardness, overall quality, and perception of healthiness and nutritional value of both types of cookies were similarly high (p &gt; 0.05). Panelists recommend the cookies. Therefore, RS4 cookies could be further investigated for their ability to improve bowel habits and re-equilibrate the microbiota of IBS patients.

Neuronutritional Approach to Fibromyalgia Management: A Narrative Review.

Fibromyalgia (FM) is a complex and common syndrome characterized by chronic widespread pain, fatigue, sleep disturbances, and various functional symptoms without clear structural or pathological causes. Affecting approximately 1-5% of the global population, with a higher prevalence in women, FM significantly impacts patients' quality of life, often leading to considerable healthcare costs and loss of productivity. Despite its prevalence, the etiology of FM remains elusive, with genetic, environmental, and psychological factors, including nutrition, being implicated. Currently, no universally accepted treatment guidelines exist, and management strategies are often symptomatic. This narrative review explores the potential of a neuronutritional approach to FM management. It synthesizes existing research on the relationship between FM and nutrition, suggesting that dietary interventions could be a promising complementary treatment strategy. Various nutritional interventions, including vitamin D, magnesium, iron, and probiotics supplementation, have shown potential in reducing FM symptoms, such as chronic pain, anxiety, depression, cognitive dysfunction, sleep disturbances, and gastrointestinal issues. Additionally, weight loss has been associated with reduced inflammation and improved quality of life in FM patients. The review highlights the anti-inflammatory benefits of plant-based diets and the low-FODMAPs diet, which have shown promise in managing FM symptoms and related gastrointestinal disorders. Supplements such as vitamin D, magnesium, vitamin B12, coenzyme Q10, probiotics, omega-3 fatty acids, melatonin, S-adenosylmethionine, and acetyl-L-carnitine are discussed for their potential benefits in FM management through various mechanisms, including anti-inflammatory effects, modulation of neurotransmitters, and improvement of mitochondrial function. In conclusion, this review underscores the importance of considering neuronutrition as a holistic approach to FM treatment, advocating for further research and clinical trials to establish comprehensive dietary guidelines and to optimize management strategies for FM patients.

Biscuits for the gut: A symphony of FODMAPs and dietary fibre in gut microbiome for irritable bowel syndrome (IBS) management

Emerging evidence suggests gut microbiome alterations significantly influence irritable bowel syndrome (IBS) symptoms with fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPs) implicated in triggering symptoms.This study investigated the impact of low and high FODMAP biscuit models on gut microbiota including: Biscuit Flour Control (BiFC), Low-FODMAP Control (LFC), Low-FODMAP High-Fibre Prototype (LFP), and Wholemeal Flour Control (WMC). Biscuits were subjected to in vitro digestion which was followed by in vitro colonic fermentation. 16S rRNA gene sequencing and fatty acid analyses were performed at the end of fermentation.Alpha diversity analysis revealed samples fermented with LFP induced higher diversity compared to samples fermented with BiFC and LFC. The relative abundance of Escherichia-Shigella was significantly lower in LFP fermentates than BiFC fermentates. LEfSe analysis showed LFC fermentates were characterized by higher levels of Citrobacter and Ligilactobacillus. Significantly reduced acetate and butyrate levels were found in LFP fermentates compared to LFC fermentates. WMC fermentates had higher acetate and propionate levels compared to other biscuit fermentates.In conclusion, incorporating low-FODMAP, high-fibre food prototypes may enhance gut microbial diversity and reduce potentially pathogenic bacteria such as Escherichia-Shigella. These findings highlight the potential of personalized dietary interventions, such as the manipulation of biscuit formulations, in modulating gut microbiota and managing IBS symptoms. Industrial relevanceThe low FODMAP diet has been developed as an effective method to moderate the symptoms of IBS patients by reducing bloating and gas in the colon. Our results revealed that the low-FODMAP, high-fibre biscuit model proved more effective than the low-FODMAP biscuit for generating a gut microbiota that could contribute to easing IBS symptoms. Future research should focus on improving this formulation and adapting it to treat the different forms of IBS. This study also demonstrates the efficacy of using colon fermentation models to devise food formulations for gut microbiome-associated diseases.

Does a low FODMAP diet reduce IBS symptoms compared with other diets?

Does a low FODMAP diet reduce IBS symptoms compared with other diets?

S2251 The Impact of Low-FODMAP Diet in Managing Irritable Bowel Syndrome: An Updated Systematic Review and Meta-Analysis

S2251 The Impact of Low-FODMAP Diet in Managing Irritable Bowel Syndrome: An Updated Systematic Review and Meta-Analysis

Dietary Interventions in Irritable Bowel Syndrome: A Systematic Review of Clinical Outcomes, Microbiota Changes, and Inflammatory Markers.

This systematic review synthesizes findings from 12 studies to evaluate the effectiveness of dietary interventions in managing irritable bowel syndrome (IBS), with a focus on low-FODMAP (fermentable oligosaccharides, disaccharides, monosaccharides, and polyols) diets, probiotics, and prebiotics. The review rigorously follows the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines and includes studies selected through comprehensive database searches. In adults diagnosed with IBS, this review assesses how effective dietary interventions, specifically low-FODMAP diets, probiotics, and prebiotics, are compared to standard management or placebo in improving clinical outcomes, modifying gut microbiota composition, and reducing inflammatory markers. Our analysis reveals that low-FODMAP diets consistently alleviate IBS symptoms and improve quality of life. However, the effectiveness of probiotics and prebiotics varies, with outcomes dependent on specific strains and individual patient microbiota profiles. The studies demonstrate significant improvements in gastrointestinal symptoms and microbiota composition, highlighting the potential of dietary strategies to beneficially modify gut health. However, the research points to the necessity of personalizing dietary approaches based on individual responses and microbiota profiles to optimize treatment efficacy. The risk of bias was assessed using the Cochrane risk-of-bias 2 tool for randomized controlled trials (RCTs) and the AMSTAR 2 tool for systematic reviews, with varying degrees of bias across the studies. This review identifies gaps in the long-term efficacy of these interventions and calls for more extensive trials to explore their sustained impacts. Our findings suggest that dietary management should be integrated into routine IBS treatment protocols and emphasize the need for further research to establish standardized dietary recommendations tailored to patient-specific characteristics.

A Starch- and Sucrose-Reduced Diet Has Similar Efficiency as Low FODMAP in IBS-A Randomized Non-Inferiority Study.

A diet with low content of fermentable oligo-, di-, and monosaccharides and polyols (FODMAP) is established treatment for irritable bowel syndrome (IBS), with well-documented efficiency. A starch- and sucrose-reduced diet (SSRD) has shown similar promising effects. The primary aim of this randomized, non-inferiority study was to test SSRD against low FODMAP and compare the responder rates (RR = ∆Total IBS-SSS ≥ -50) to a 4-week dietary intervention of either diet. Secondary aims were to estimate responders of ≥100 score and 50% reduction; effects on extraintestinal symptoms; saturation; sugar craving; anthropometric parameters; and blood pressure. 155 IBS patients were randomized to SSRD (n = 77) or low FODMAP (n = 78) for 4 weeks, with a follow-up 5 months later without food restrictions. The questionnaires Rome IV, IBS-severity scoring system (IBS-SSS), and visual analog scale for IBS (VAS-IBS) were completed at baseline and after 2 and 4 weeks and 6 months. Weight, height, waist circumference, and blood pressures were measured. Comparisons were made within the groups and between changes in the two groups. There were no differences between groups at baseline. The responder rate of SSRD was non-inferior compared with low FODMAPs at week 2 (79.2% vs. 73.1%; p = 0.661;95% confidence interval (CI) = -20-7.2) and week 4 (79.2% vs. 78.2%; p = 1.000;95%CI = -14-12). Responder rate was still high when defined stricter. All gastrointestinal and extraintestinal symptoms were equally improved (p < 0.001 in most variables). SSRD rendered greater reductions in weight (p = 0.006), body mass index (BMI) (p = 0.005), and sugar craving (p = 0.05), whereas waist circumference and blood pressure were equally decreased. Weight and BMI were regained at follow-up. In the SSRD group, responders at 6 months still had lowered weight (-0.7 (-2.5-0.1) vs. 0.2 (-0.7-2.2) kg; p = 0.005) and BMI (-0.25 (-0.85-0.03) vs. 0.07 (-0.35-0.77) kg/m2; p = 0.009) compared with baseline in contrast to non-responders. Those who had tested both diets preferred SSRD (p = 0.032). In conclusion, a 4-week SSRD intervention was non-inferior to low FODMAP regarding responder rates of gastrointestinal IBS symptoms. Furthermore, strong reductions of extraintestinal symptoms were found in both groups, whereas reductions in weight, BMI, and sugar craving were most pronounced following SSRD.

THE ROLE OF LIFESTYLE-RELATED TREATMENTS FOR IRRITABLE BOWEL SYNDROME

Introduction: The role of diet and lifestyle in Irritable Bowel Syndrome (IBS) mainly involves alleviating symptoms and improving the quality of life for patients. Diet plays a significant role through the identification and avoidance of trigger foods, the introduction of an appropriate amount of fiber, and adherence to specific guidelines. Lifestyle, including regular physical activity, stress reduction techniques, and healthy sleep habits, also contributes to the reduction of bowel discomfort. Aim of the study: The aim of this study is to examine the relationship between diet and lifestyle, and the occurrence and course of Irritable Bowel Syndrome. Material and Methods of Research: A literature review focused on keywords related to the topic was performed using databases such as PubMed and Google Scholar, as well as textbooks and articles on websites. Results: Irritable Bowel Syndrome (IBS) is a chronic functional disorder of the gastrointestinal tract, primarily characterized by abdominal pain and changes in bowel habits. Dietary modifications, such as a lowFODMAP diet, and lifestyle factors, including physical activity levels, stress management, and meal regularity, significantly influence the course of the disease. There are gender differences in symptomatology and psychosocial impact as well as gender-specific responses to pharmaceutical treatments. Ongoing research is needed to better understand the mechanisms underlying IBS and to optimize therapeutic strategies. Conclusion: The effectiveness of IBS therapy requires a comprehensive approach that includes dietary modifications, increased daily physical activity, learning to manage emotions, and regular collaboration with a doctor. Understanding and implementing these elements are crucial for effectively alleviating symptoms and improving the functioning of patients with Irritable Bowel Syndrome.

Microbiome-driven IBS metabotypes influence response to the low FODMAP diet: insights from the faecal volatome

Irritable bowel syndrome (IBS) is a common and debilitating disorder manifesting with abdominal pain and bowel dysfunction. A mainstay of treatment is dietary modification, including restriction of FODMAPs (fermentable oligosaccharides, disaccharides, monosaccharides and polyols). A greater response to a low FODMAP diet has been reported in those with a distinct IBS microbiome termed IBS-P. We investigated whether this is linked to specific changes in the metabolome in IBS-P. Solid phase microextraction gas chromatography-mass spectrometry was used to examine the faecal headspace of 56 IBS cases (each paired with a non-IBS household control) at baseline, and after four-weeks of a low FODMAP diet (39 pairs). 50% cases had the IBS-P microbial subtype, while the others had a microbiome that more resembled healthy controls (termed IBS-H). Clinical response to restriction of FODMAPs was measured with the IBS-symptom severity scale, from which a pain sub score was calculated. Two distinct metabotypes were identified and mapped onto the microbial subtypes. IBS-P was characterised by a fermentative metabolic profile rich in short chain fatty acids (SCFAs). After FODMAP restriction significant reductions in SCFAs were observed in IBS-P. SCFA levels did not change significantly in the IBS-H group. The magnitude of pain and overall symptom improvement were significantly greater in IBS-P compared to IBS-H (p=0.016 and p=0.026, respectively). Using just five metabolites, a biomarker model could predict microbial subtype with accuracy (AUROC 0.797, sensitivity 78.6% (95% CI: 0.78-0.94), specificity 71.4% (95% CI: 0.55-0.88). A metabotype high in SCFAs can be manipulated by restricting fermentable carbohydrate, and is associated with an enhanced clinical response to this dietary restriction. This implies that SCFAs harbour pro-nociceptive potential when produced in a specific IBS niche. By ascertaining metabotype, microbial subtype can be predicted with accuracy. This could allow targeted FODMAP restriction in those seemingly primed to respond best. This research was co-funded by Addenbrooke's Charitable Trust, Cambridge University Hospitals and the Wellcome Sanger Institute, and supported by the NIHR Cambridge Biomedical Research Centre (BRC-1215-20014).

Relationship between Markers of Gut Barrier Function and Erythrocyte Membrane PUFAs in Diarrhea-Predominant IBS Patients Undergoing a Low-FODMAP Diet.

Many patients with irritable bowel syndrome (IBS) have a compromised intestinal barrier associated with low-grade inflammation. Polyunsaturated fatty acids (PUFAs) are potential mediators of inflammation: omega-6 PUFAs are pro-inflammatory, while omega-3 PUFAs are antioxidant and anti-inflammatory. Zonulin is a potential biomarker for small intestinal permeability (s-IP). This study investigated the relationship between PUFAs and gastrointestinal (GI) barrier integrity in IBS patients with predominant diarrhea (IBS-D). We evaluated GI barrier function indicators in the urine and bloodstream and erythrocyte membrane PUFA composition in 38 IBS-D patients (5 men, 33 women, 44.11 ± 1.64 years), categorized at baseline by fecal zonulin levels into high (≥107 ng/mL, H-FZ) and normal (<107 ng/mL N-FZ) groups. Evaluations were conducted prior to and following a 12-week diet low in FODMAPs (LFD). At baseline, H-FZ patients had s-IP significantly higher than the reference value, lower n-3 PUFAs levels, and higher n-6/n-3 PUFAs and arachidonic acid (AA) to eicosapentaenoic acid (EPA) ratios than N-FZ. After LFD, H-FZ patients showed significant increases in n-3 PUFAs levels; decreases in n-6 PUFAs, n-6/n-3 PUFAs and AA/EPA ratios; and improved s-IP. The n-6/n-3 PUFAs ratio positively correlated with fecal zonulin levels in all subjects. These findings highlight the relationship between PUFAs and the intestinal barrier, suggesting their role in IBS-D pathophysiology and confirming the positive effects of LFD in managing IBS-D.

Effectiveness of the diet low in fermentable carbohydrates as a treatment in adults diagnosed with irritable bowel syndrome: a Systematic Review

Currently the diet low in fermentable carbohydrates (FODMAP) is has established itself as a first-line strategy as a treatment for IBS in adults, so the purpose of this study is to analyze the effectiveness of the low diet in fermentable carbohydrates, as a treatment in adult patients diagnosed with IBS. Method: Systematic review (S.R.) based on randomized clinical trials (ECA) obtained from the databases Web of Science, PubMed, Cochrane Library, Scopus, EBSCO and Proquest. RCTs that included adults over 18 were reviewed years and older, both sexes, diagnosed with irritable bowel syndrome (IBS), who have contemplated a FODMAP restriction &lt;112 gr/day, compared to a high FODMAP diet, regular diet with healthy habits. The risk of bias, according to the Cochrane collaboration. Results: five RCTs were found from Iran, Australia, China and Sweden, where four of them showed changes on the study variables: pain and distention abdominal, visceral hypersensitivity, alterations in depositional habits, transit abnormal levels of gas and vomiting, compared to their respective control groups. Conclusion: the evidence collected suggests that a low FODMAP diet in adults diagnosed with IBS significantly reduce the associated classic symptoms, generating decreases on the study variables, however, it is essential have adequate dietary advice from a professional nutritionist, to avoid nutritional deficiency and possible side effects