Diet In Irritable Bowel Syndrome Research Articles

Predicting symptom response and quality of life to the low FODMAP diet in irritable bowel syndrome: a 6-month longitudinal study

The low fermentable oligosaccharide, disaccharide, monosaccharide and polyol (FODMAP) diet is recommended as a first line therapeutic management strategy for irritable bowel syndrome (IBS)(1). The low FODMAP diet is supported by meta-analytical evidence(2), and demonstrates acceptability and effectiveness for improving symptoms and quality of life (QoL) in 50-75% of individuals with IBS. However, a subset of individuals (25-50%) do not respond to the diet(3). The identification of individual-level predictors of treatment response across all three phases of the low FODMAP diet is currently lacking. The study aims were to assess psychological predictors of symptom and QoL response to the low FODMAP diet in patients with IBS. Adults with IBS underwent a three-phase low FODMAP diet, guided by individualised dietetic education. Predictor variables included levels of depressive, anxiety, and extraintestinal somatic symptoms, stress, treatment beliefs and expectations, behavioural avoidance, and illness perceptions. Symptom severity and QoL were the main outcomes. Questionnaires assessing psychological predictors, symptoms and QoL were administered at five points: pre-dietitian (week 0), post-dietitian, end of elimination (week 5), end of reintroduction (week 13), and end of personalisation (week 25) phases. Latent class growth analysis was used to identify classes of response trajectories for symptoms. Linear mixed models were used to test the effect of baseline psychological scores on symptoms and QoL over time. Cross lagged panel models determined the directional predictive relationship between psychological predictors and symptom severity. 112 participants (89% F) median age 30 ± 17 years were included. There were three classes of symptom response trajectories, including ‘non-improvers’ (21.3% of participants) with high initial symptom severity and minimal improvement, ‘improvers’ (22.5% of participants) with low initial symptom severity and significant improvement, and an ‘intermediate’ group (56.2% of participants) with moderate initial symptom severity and significant improvement. Higher treatment beliefs predicted a stronger initial symptom response (effect on linear slope p = 0.036). Lower gut-specific anxiety, as well as higher levels of personal and treatment control at baseline predicted a stronger reduction in IBS symptom severity and improved QoL from week 0 to week 25. Participants with higher levels of baseline psychological symptoms and negative illness perceptions (i.e., lower emotional representations) predicted a stronger initial and later QoL response (effect on linear (p = 0.006) and quadratic (p = 0.049) slopes). Increased cyclical time beliefs predicted poorer initial and later QoL response (effect on linear (p = 0.015) and quadratic (p = 0.029) slopes). Individuals experiencing lower to mid-range symptom severity at baseline had greater improvement with the low FODMAP diet. Lower anxiety, positive illness views and higher treatment beliefs predict better QoL and symptom response. Personalised strategies are crucial for optimising low FODMAP diet effectiveness in IBS.

Assessing ‘response’ to the low-FODMAP diet in irritable bowel syndrome: Should we be reporting harder primary endpoints?

The low-FODMAP diet (LFD) has become almost synonymous with IBS care, yet the challenges associated with this rigorous therapeutic approach are often underacknowledged. Despite positive outcomes in RCTs, comparator groups frequently exhibit substantial response rates, raising questions about the definition of 'response'. Whilst the assessment of response in drug trials has evolved to utilize the more stringent FDA/EMA primary clinical endpoints, trials of the LFD have not yet followed. The aim of this article is to opine whether the current approach to the measurement of clinical response to the LFD in clinical trials should be reconsidered. A comprehensive literature review of LFD clinical trials from the past decade was conducted, focusing on recorded response metrics for primary clinical endpoints. While response definitions vary, the 50-point IBS-SSS delta emerged as the predominant metric. Notably, no trials to date have adopted the more stringent primary clinical endpoints used in drug trials. Other response measures included binary response metrics (such as 'adequate clinical response'), changes in visual analogue scales or stool form/output, reductions in abdominal pain, as well as changes the magnitude of the IBS-SSS delta. Whether these metrics correspond to a clinically meaningful improvement for the patient is less clear, and as such aligning patient-clinician expectations can be challenging. A paradigm shift in the conceptualization of 'response' coupled with an emphasis on harder clinical endpoints in the context of clinical trials may serve to better justify the trade-off between symptom-improvement and the inherent challenges associated with this burdensome therapeutic approach.

Efficacy and Findings of a Blinded Randomized Reintroduction Phase for the Low FODMAP Diet in Irritable Bowel Syndrome

The efficacy of a low fermentable oligo-, di-, monosaccharides and polyols (FODMAP) diet in irritable bowel syndrome (IBS) is well established. After the elimination period, a reintroduction phase aims to identify triggers. We studied the impact of a blinded reintroduction using FODMAP powders to objectively identify triggers and evaluated the effect on symptoms, quality of life, and psychosocial comorbidities. Responders to a 6-week low FODMAP diet, defined by a drop in IBS symptom severity score (IBS-SSS) compared with baseline, entered a 9-week blinded randomized reintroduction phase with 6 FODMAP powders (fructans, fructose, galacto-oligosaccharides, lactose, mannitol, sorbitol) or control (glucose). A rise in IBS-SSS (≥50 points) defined a FODMAP trigger. Patients completed daily symptom diaries and questionnaires for quality of life and psychosocial comorbidities. In 117 recruited patients with IBS, IBS-SSS improved significantly after the elimination period compared with baseline (150 ± 116 vs 301 ± 97, P < .0001, 80% responders). Symptom recurrence was triggered in 85% of the FODMAP powders, by an average of 2.5 ± 2 FODMAPs/patient. The most prevalent triggers were fructans (56%) and mannitol (54%), followed by galacto-oligosaccharides, lactose, fructose, sorbitol, and glucose (respectively 35%, 28%, 27%, 23%, and 26%) with a significant increase in abdominal pain at day 1 for sorbitol/mannitol, day 2 for fructans/galacto-oligosaccharides, and day 3 for lactose. We confirmed the significant benefit of the low FODMAP diet in tertiary-care IBS. A blinded reintroduction revealed a personalized pattern of symptom recurrence, with fructans and mannitol as the most prevalent, and allows the most objective identification of individual FODMAP triggers. Ethical commission University hospital of Leuven reference number: s63629; Clinicaltrials.gov number: NCT04373304.

Exploration of differential responses to FODMAPs and gluten in people with irritable bowel syndrome- a double-blind randomized cross-over challenge study

IntroductionThere is large variation in response to diet in irritable bowel syndrome (IBS) and determinants for differential response are poorly understood.ObjectivesOur aim was to investigate differential clinical and molecular responses to provocation with fermentable oligo-, di-, monosaccharides, and polyols (FODMAPs) and gluten in individuals with IBS.MethodsData were used from a crossover study with week-long interventions with either FODMAPs, gluten or placebo. The study also included a rapid provocation test. Molecular data consisted of fecal microbiota, short chain fatty acids, and untargeted plasma metabolomics. IBS symptoms were evaluated with the IBS severity scoring system. IBS symptoms were modelled against molecular and baseline questionnaire data, using Random Forest (RF; regression and clustering), Parallel Factor Analysis (PARAFAC), and univariate methods.ResultsRegression and classification RF models were in general of low predictive power (Q2 ≤ 0.22, classification rate < 0.73). Out of 864 clustering models, only 2 had significant associations to clusters (0.69 < CR < 0.73, p < 0.05), but with no associations to baseline clinical measures. Similarly, PARAFAC revealed no clear association between metabolome data and IBS symptoms.ConclusionDifferential IBS responses to FODMAPs or gluten exposures could not be explained from clinical and molecular data despite extensive exploration with different data analytical approaches. The trial is registered at www.clinicaltrials.gov as NCT03653689 31/08/2018.

The Role of the FODMAP Diet in IBS.

The low FODMAP (fermentable oligosaccharide, disaccharide, monosaccharide, and polyol) diet is a beneficial therapeutic approach for patients with irritable bowel syndrome (IBS). However, how the low FODMAP diet works is still not completely understood. These mechanisms encompass not only traditionally known factors such as luminal distension induced by gas and water but also recent evidence on the role of FOMAPs in the modulation of visceral hypersensitivity, increases in intestinal permeability, the induction of microbiota changes, and the production of short-chain fatty acids (SCFAs), as well as metabolomics and alterations in motility. Although most of the supporting evidence is of low quality, recent trials have confirmed its effectiveness, even though the majority of the evidence pertains only to the restriction phase and its effectiveness in relieving abdominal bloating and pain. This review examines potential pathophysiological mechanisms and provides an overview of the existing evidence on the effectiveness of the low FODMAP diet across various IBS subtypes. Key considerations for its use include the challenges and disadvantages associated with its practical implementation, including the need for professional guidance, variations in individual responses, concerns related to microbiota, nutritional deficiencies, the development of constipation, the necessity of excluding an eating disorder before commencing the diet, and the scarcity of long-term data. Despite its recognized efficacy in symptom management, acknowledging these limitations becomes imperative for a nuanced comprehension of the role of a low FODMAP diet in managing IBS. By investigating its potential mechanisms and evidence across IBS subtypes and addressing emerging modulations alongside limitations, this review aims to serve as a valuable resource for healthcare practitioners, researchers, and patients navigating the intricate landscape of IBS.

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

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? Forty Rome III IBS and 20 healthy controls underwent an eight-hour H2 breath test following a low- (rice, brinjal, corn, and banana [450Kcal]) and a high-FODMAP meal (wheat, kidney bean, pulse, and card [450Kcal]). Breath H2 (every 15min) 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. 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 (18PPM [IQR 10.5-23] vs 6 [0-7.2]; P<0.001). A positive FMCT (breath H2 >10PPM 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. The novel FMCT predicts response to a low-FODMAP diet in IBS.

Irritable bowel syndrome – controversies in diagnosis and management

ABSTRACT Introduction The irritable bowel syndrome (IBS) is the best-recognized disorder of gut brain interactions (DGBI). However, it is controversial if the Rome IV criteria iteration for IBS diagnosis is fit for purpose. Areas covered This review critically evaluates Rome IV criteria for diagnosis of IBS and addresses clinical considerations in IBS treatment and management, including dietary factors, biomarkers, disease mimics, symptom severity, and subtypes. The role of diet in IBS is critically reviewed along with the influence of the microbiota, including small intestinal bacterial overgrowth. Expert opinion Emerging data suggest the Rome IV criteria are more suitable for identifying severe IBS and least useful for sub-diagnostic patients who are still likely to benefit from IBS treatment. Despite convincing evidence that IBS symptoms are diet-driven and often postprandial, a relationship to eating is not a Rome IV diagnostic criterion. Few IBS biomarkers have been identified, suggesting the syndrome is too heterogeneous to be measured by a single marker, and combined biomarker, clinical, dietary, and microbial profiling may be needed for objective characterization. With many organic diseases mimicking and overlapping with IBS, it’s important clinicians are knowledgable about this to mitigate the risk of missing comorbid organic intestinal disease and to optimally treat IBS symptoms.

Top studies of 2022 relevant to primary care: From the PEER team.

To summarize 10 high-quality medical articles published in 2022 that are relevant to primary care physicians. Routine surveillance of tables of contents in relevant medical journals and EvidenceAlerts was conducted by the PEER (Patients, Experience, Evidence, Research) team, a group of primary care health care professionals with an interest in evidence-based medicine. Articles were selected and ranked based on relevance to practice. Published articles from 2022 most likely to influence primary care practice examined the following subjects: reducing dietary sodium for heart failure; timing of blood pressure medications to reduce cardiovascular outcomes; adding as-needed corticosteroids to rescue puffers for asthma exacerbations; influenza vaccination after myocardial infarction; comparing various medications for diabetes management; tirzepatide for weight loss; low FODMAP diet for irritable bowel syndrome; prune juice for constipation; impact of regular acetaminophen use on patients with hypertension; and time required to care for patients in primary care. Two "honourable mention" studies are also summarized. Research published in 2022 yielded several high-quality articles on various conditions relevant to primary care, including hypertension, heart failure, asthma, and diabetes.

Commentary: When applying dietary therapies for gastrointestinal conditions, family values, culture, and social challenges matter.

Some gastrointestinal conditions now have diet as a cornerstone to therapy. Three examples include the low-fermentable, oligosaccharide, disaccharide, monosaccharide, and polyol diet for irritable bowel syndrome, a gluten-free diet for celiac disease, and a hypoallergenic diet for eosinophilic esophagitis. All have been shown to be effective in Western or highly industrialized countries. However, these gastrointestinal conditions occur worldwide. Less is known regarding the effectiveness of dietary therapies in cultures and regions of dense religious and traditional practices where food is a central focus. This includes South Asia, the Mediterranean region, Africa, the Middle East, South America, and within Indigenous communities. Hence, there is a need to reproduce dietary intervention studies within cultures of dense traditional dietary practices to understand the applicability and acceptability of dietary therapy to establish generalizability. Furthermore, there is a need for nutrition experts to have a deep understanding of various cultural cuisines, practices, values, and customs. To achieve this, increasing the diversity of students in the sciences and having a diverse workforce of nutrition experts and health professionals that reflects the patient population will allow for more personalized care. In addition, there are social challenges, including a lack of medical insurance coverage, the cost of dietary interventions, and inconsistent nutrition messaging. Although there are many cultural considerations and social challenges to implementing effective dietary interventions around the world, these barriers are addressable through research methodologies that address culture and society challenges, and enhanced training of dietitians.

Efficacy of a Restrictive Diet in Irritable Bowel Syndrome: A Systematic Review and Network Meta-analysis.

Dietary factors can aggravate the symptoms of irritable bowel syndrome (IBS). Many IBS patients try restrictive diets to relieve their symptoms, but the types of diets with an exacerbating factor are unknown. Therefore, this paper reports the results of a systematic review and network meta-analysis of randomized-controlled trials (RCTs) reviewing the efficacy of food restriction diets in IBS. The MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and Clinicaltrials.gov databases were searched until July 21, 2021, to retrieve RCTs assessing the efficacy of restriction diets in adults with IBS. Two independent reviewers performed the eligibility assessment and data abstraction. RCTs that evaluated a restriction diet versus a control diet and assessed the improvement in global IBS symptoms were included. These trials reported a dichotomous assessment of the overall response to therapy. A total of 1,949 citations were identified. After full-text screening, 14 RCTs were considered eligible for the systematic review and network meta-analysis. A starch- and sucrose-reduced diet and a diet with low-fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPs) showed significantly better results than a usual diet. Symptom flare-ups in patients on a gluten- free diet were also significantly lower than in those on high-gluten diets. These findings showed that the starch- and sucrose-reduced, low FODMAP, and gluten-free diets had superior effects in reducing IBS symptoms. Further studies, including head-to-head trials will be needed to establish the effectiveness of dietary restrictions on IBS symptoms.

Low FODMAP diet in irritable bowel syndrome: a review of recent clinical trials and meta-analyses.

The low fermentable oligosaccharides, disaccharides, monosaccharides and polyol (FODMAP) diet is widely used in the dietary management of irritable bowel syndrome (IBS). The aim of this review is to summarize recent evidence regarding the use of the low FODMAP diet in IBS and other gastrointestinal disorders from recent clinical trials and meta-analyses. Several recent systematic reviews and meta-analyses support the use of low FODMAP restriction for global symptoms in IBS in the short term. Uncontrolled follow-up studies show that at least 50% of individuals experience symptom relief following restriction, reintroduction and personalization in the long term. Although evidence from comparative trials in IBS suggests potential benefit of less burdensome approaches (e.g. standard IBS diet and low lactose diet) many studies are insufficiently powered. One established mechanism is colonic gas production that may induce pain signalling measurable in the brain, however altered gastrointestinal epithelial integrity and shifts in microbiome composition and function may also be involved. Quality trials of the low FODMAP diet are emerging and have been transformational in supporting the widespread application to IBS management in some areas (e.g. short-term effectiveness), whereas other areas still require considerable improvements in research evidence (e.g. long-term effectiveness, mechanisms and educational delivery).

A Starch- and Sucrose-Reduced Diet in Irritable Bowel Syndrome Leads to Lower Circulating Levels of PAI-1 and Visfatin: A Randomized Controlled Study.

Irritable bowel syndrome (IBS) is characterized by gastrointestinal symptoms. Overweight and increased risk of metabolic syndromes/diabetes are observed in IBS, conditions associated with plasminogen activator inhibitor-1 (PAI-1) and visfatin. The aim of this study was to measure blood levels of AXIN1, cholecystokinin (CCK), enkephalin, ghrelin, neuropeptide Y (NPY), PAI-1, and visfatin before and after a 4-week intervention with a starch- and sucrose-reduced diet (SSRD). A total of 105 IBS patients were randomized to either SSRD (n = 80) or ordinary diet (n = 25). Questionnaires were completed, and blood was analyzed for AXIN1 and hormones. AXIN1 (p = 0.001) and active ghrelin levels (p = 0.025) were lower in IBS than in healthy volunteers at baseline, whereas CCK and enkephalin levels were higher (p < 0.001). In the intervention group, total IBS-symptom severity score (IBS-SSS), specific gastrointestinal symptoms, psychological well-being, and the influence of intestinal symptoms on daily life were improved during the study, and weight decreased (p < 0.001 for all), whereas only constipation (p = 0.045) and bloating (p = 0.001) were improved in the control group. PAI-1 levels tended to be decreased in the intervention group (p = 0.066), with a difference in the decrease between groups (p = 0.022). Visfatin levels were decreased in the intervention group (p = 0.007). There were few correlations between hormonal levels and symptoms. Thus, this diet not only improves IBS symptoms but also seems to have a general health-promoting effect.

Long-term personalized low FODMAP diet in IBS.

Irritable bowel syndrome (IBS) patients often resort to dietary interventions to manage their symptoms, as these are frequently exacerbated by various food items. A diet low in fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPs) is now considered by many a first-line treatment option for IBS, as it has been found to be superior to alternative dietary interventions. However, concerns have been raised as restricting fermentable carbohydrates might result in nutritional deficits or alter composition and function of the gut microbiome in the long term. The study by Staudacher et al., published in this issue of the journal, is the first prospective study to follow IBS patients after completing all three phases of the low FODMAPs diet (restriction, reintroduction, and personalization), demonstrating that this is safe and effective in long-term, when patients are supervised by a dietician. This mini-review provides an up-to-date overview of the use of fermentable carbohydrate's restrictions for symptom management in IBS patients, while summarizing the current knowledge on the possible mechanisms of action behind low fermentable carbohydrate diet efficacy.

Cognitive Behavioral Therapy Versus the Low FODMAP Diet for Irritable Bowel Syndrome: A Non-Inferiority Comparison of Two Self-Help Books

Background: IBS is a highly prevalent, chronic gastrointestinal (GI) disorder of gut-brain interaction that can lead to considerable distress and disability. Although IBS does not respond particularly well to standard medical care, empirically supported treatments exist, including CBT and the low FODMAP diet. Many patients with IBS seek self-help and adjunctive treatments to supplement traditional medical care. Therefore, it is important to rigorously test some of those publicly available options to see if they provide measurable benefit to consumers. Aims: This study compared the efficacy of 2 self-help books (one cognitive-behavioral therapy or CBT book and one low FODMAP diet book) for irritable bowel syndrome (IBS). Method: This study was a randomized, controlled, optional cross-over, single-blind, non-inferiority trial of 2 popular self-help books with 3 months of longitudinal follow-up. The books were Reclaim Your Life from IBS and The Complete Low FODMAP Diet Book. Result: Immediately post-treatment, participants in both conditions showed significant improvement in health-related quality of life (HRQL), GI symptom severity, catastrophizing, anxiety about visceral sensations, and depressive symptoms. There were no significant between-group differences at post-treatment in HRQL; although, the low FODMAP group did show greater declines in GI symptom severity. By 3-month follow-up, both groups continued to show significant improvement over baseline in HRQL, and there were no significant between group-differences on any measure. Conclusion: Reading either book with no professional guidance resulted in substantial improvement in patients with self-reported IBS.

Supplementing Dietary Fibers With a Low FODMAP Diet in Irritable Bowel Syndrome: A Randomized Controlled Crossover Trial

Institution of a diet low in fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAPs) in patients with irritable bowel syndrome (IBS) may lead to inadequate fiber intake. This trial aimed to investigate the effects of supplementing specific fibers concomitantly with a low FODMAP diet on relevant clinical and physiological indices in symptomatic patients with IBS. A double-blind crossover trial was conducted in which 26 patients with IBS were randomly assigned to 1 of 3 low FODMAP diets differing only in total fiber content: control, 23 g/d; sugarcane bagasse, 33 g/d; or fiber combination (sugarcane bagasse with resistant starch), 45 g/d. Each diet lasted 14 days with most food provided and ≥21 days' washout between. Endpoints were assessed during baseline and dietary interventions. From a median IBS Severity Scoring System total score at baseline of 305, all diets reduced median scores by >50 with no differences in rates of symptom response between the diets: control (57%), sugarcane bagasse (67%), fiber combination (48%) (P= .459). Stool output was ∼50% higher during the fiber-supplemented vs control diets (P < .001 for both). While there were no overall differences overall in stool characteristics, descriptors, and water content, or in gastrointestinal transit times, supplementation with sugarcane bagasse normalized both low stool water content and slow colonic transit from during the control diet. Concomitant supplementation of fibers during initiation of a low FODMAP diet did not alter symptomatic response in patients with IBS but augmented stool bulk and normalized low stool water content and slow transit. Resistant starch did not exert additional symptomatic benefits over sugarcane bagasse alone. (Australia and New Zealand Clinical Trial Registry; Number, ACTRN12619000691145).

World Gastroenterology Organisation Global Guidelines: Diet and the Gut.

World Gastroenterology Organisation Global Guidelines: Diet and the Gut.

Efficacy of a low FODMAP diet in irritable bowel syndrome: systematic review and network meta-analysis

ObjectiveA diet low in fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAP) is recommended for irritable bowel syndrome (IBS), if general lifestyle and dietary advice fails. However, although the impact of...

Nutrition communication about low FODMAP diet in irritable bowel syndrome (IBS) and small intestinal bacterial overgrowth (SIBO) in Thai healthcare practitioners

Nowadays, communication is influential regarding the various communication channels that make the information spreading effectively to the audiences. Additionally, the senders are also another factor creating credibility to the receivers, particularly to the healthcare-related issue which is necessary to be guaranteed by the medical specialists. The Low FODMAP is a therapeutic diet which is recommended for Irritable Bowel Syndrome (IBS) and Small Intestinal Bacterial Overgrowth (SIBO) patients. However, this diet has not been practiced widespread among Thai healthcare practitioners. As a matter of fact, these practitioners are familiar with a great number of diseases and closely well-educated with healthcare issues, they would significantly hold credibility affecting the medical usage to the society. Consequently, this article aims to educate all the staff in the healthcare and medical industry to gain sufficient knowledge of low FODMAP and be able to apply for further development.Keywords: nutrition communication, Low FODMAP, IBS, SIBO

Impact of Diet on Symptoms of the Irritable Bowel Syndrome.

Irritable bowel syndrome (IBS), with its key features of abdominal pain and disturbed bowel habit, is thought by both patients and clinicians to be strongly influenced by diet. However, the complexities of diet have made identifying specific food intolerances difficult. Eating disorders can masquerade as IBS and may need specialist treatment. While typical food allergy is readily distinguished from IBS, the mechanisms of gut-specific adverse reactions to food are only just being defined. These may include gut-specific mast cell activation as well as non-specific activation by stressors and certain foods. Visceral hypersensitivity, in some cases mediated by mast cell activation, plays a key part in making otherwise innocuous gut stimuli painful. Rapidly fermented poorly absorbed carbohydrates produce gaseous distension as well as short-chain fatty acids and lowering of colonic pH which may cause symptoms in IBS patients. Limiting intake of these in low FODMAP and related diets has proven popular and apparently successful in many patients. Existing diet, colonic microbiota and their metabolic products may be helpful in predicting who will respond. Wheat intolerance may reflect the fact that wheat is often a major source of dietary FODMAPs. It may also be either a forme fruste of coeliac disease or non-specific immune activation. Wheat exclusion can be successful in some of these patients. More research is needed to fully understand the mechanisms of food intolerances and how to best ameliorate them in a personalised medicine approach to diet in IBS.

Irritable Bowel Syndrome in Pregnancy.

Irritable bowel syndrome (IBS) affects a significant percentage of the general population and is more common in women. A large proportion of women affected with IBS are of childbearing age; however, there is a paucity of studies and guidelines to specifically address the epidemiology, course, maternal/fetal prognosis, or management of IBS in pregnancy. This scarcity of literature on IBS and pregnancy poses significant challenges to healthcare providers in counseling and managing patients. In this comprehensive review, we summarize the current literature and knowledge gaps regarding the effects of pregnancy on IBS and vice versa, along with the efficacy and safety profiles of commonly used IBS diets and medications in pregnancy. The management of pregnant women with IBS should be multidisciplinary, with emphasis on education and judicious use of dietary modifications and pharmacologic options that are deemed relatively safe during pregnancy.