Presence and characteristics of disordered eating and orthorexia in irritable bowel syndrome.

INTRODUCTION: Orthorexia, a harmful obsession with eating healthily, may develop from illnesses characterized by dietary restriction, including irritable bowel syndrome (IBS) and eating disorders (ED). Evidence of disordered eating in IBS exists, but orthorexia has not been assessed. This cross-sectional study in adults (≥18 years) assessed presence and characteristics of disordered eating and orthorexia in IBS, compared to control subjects (CS) and ED. METHODS: IBS participants met Rome IV, and ED participants met DSM-5 criteria. Disordered eating was assessed using "sick, control, one-stone, fat, food" (SCOFF, ≥2 indicating disordered eating), and orthorexia by the eating habits questionnaire (EHQ). Secondary measures included stress (PSS); anxiety (HADS-A); food-related quality of life (Fr-QoL), and dietary intake (CNAQ). KEY RESULTS: In 202 IBS (192 female), 34 ED (34 female), and 109 CS (90 female), more IBS (33%) and ED (47%) scored SCOFF≥2 compared to CS (16%, p < 0.001, chi-square). IBS and ED had higher orthorexia symptom severity compared to CS (EHQ IBS 82.9 ± 18.1, ED 90.1 ± 19.6, and CS 73.5 ± 16.9, p < 0.001, one-way ANOVA). IBS and ED did not differ for SCOFF or EHQ (p > 0.05). Those with IBS and disordered eating had higher orthorexia symptom severity (EHQ 78.2 ± 16.6 vs. 92.4 ± 17.5, p < 0.001, independent t-test), worse symptoms (IBS-SSS 211.0 ± 78.4 vs. 244.4 ± 62.5, p = 0.008, Mann-Whitney U test), higher stress (p < 0.001, independent t-test), higher anxiety (p = 0.002, independent t-test), and worse FR-QoL (p < 0.001, independent t-test). CONCLUSIONS AND INFERENCES: Disordered eating and orthorexia symptoms occur frequently in IBS, particularly in those with worse gastrointestinal symptoms, higher stress, and anxiety. Clinicians could consider these characteristics when prescribing dietary therapies.

The Effectiveness of a Lactobacilli-Based Probiotic Food Supplement on Bone Mineral Density and Bone Metabolism in Australian Early Postmenopausal Women: Protocol for a Double-Blind Randomized Placebo-Controlled Trial.

Osteoporosis affects one in three women over the age of 50 and results in fragility fractures. Oestrogen deficiency during and after menopause exacerbates bone loss, accounting for higher prevalence of fragility fractures in women. The gut microbiota (GM) has been proposed as a key regulator of bone health, as it performs vital functions such as immune regulation and biosynthesis of vitamins. Therefore, GM modulation via probiotic supplementation has been proposed as a target for potential therapeutic intervention to reduce bone loss. While promising results have been observed in mouse model studies, translation into human trials is limited. Here, we present the study protocol for a double-blind randomized controlled trial that aims to examine the effectiveness of three lactobacilli strains on volumetric bone mineral density (vBMD), trabecular, and cortical microstructure, as measured using High Resolution peripheral Quantitative Computed Tomography (HR-pQCT). The trial will randomize 124 healthy early postmenopausal women (up to 8 years from menopause) to receive either probiotic or placebo administered once daily for 12 months. Secondary outcomes will investigate the probiotics' effects on areal BMD and specific mechanistic biomarkers, including bone metabolism and inflammatory markers. The trial is registered with Australian New Zealand Clinical Trials Registry (ACTRN12621000810819).

Nutrition employability and graduate readiness: The Australian Working in Nutrition study.

BACKGROUND: Nutrition science graduates contribute to the nutrition workforce by bringing specialist knowledge and skills needed to address future food challenges. This study aims to provide a snapshot of the current employment landscape for nutrition science graduates in Australia and how well their degrees prepare them for employment. METHOD: A cross-sectional survey of Australian tertiary nutrition graduates was conducted to explore tertiary training, employment pathways and their perceived preparedness for practice. RESULTS: This study included a final sample of 119 graduates from 17 Australian tertiary institutions. Almost two-thirds of respondents had completed further training. Most graduates (77%, n = 91) had worked in a food, nutrition science or health-related role after their degree; the most frequently cited employment settings were government or public health organisations; research, not-for-profit or nongovernment organisations; and the food industry. Work-integrated learning was identified as a key predictor of graduates working in a role that differed from their expectations as a student. The skill categories developed during nutrition training that were most valued in the workplace included nutrition and scientific knowledge, and professional and communication skills. CONCLUSIONS: This study offers first insights into the current employment landscape for nutrition graduates across Australia. Findings show that current nutrition science professionals are highly qualified and prepared to navigate the evolving demands of nutrition practice. Regular review of graduate employment will inform nutrition science curriculum to enable graduates to be well equipped in the face of dynamic practice settings.

Assessing the presence and motivations of orthorexia nervosa among athletes and adults with eating disorders: a cross-sectional study.

PURPOSE: Orthorexia nervosa involves restricting diet based on quality rather than quantity. Although orthorexia is well reported in many at-risk populations, limited data addresses its presence in individuals with eating disorder history (EDs) or athletes. We aimed to identify the presence and potential drivers of orthorexia in adults with EDs and endurance athletes, compared to control subjects. METHODS: Participants ≥ 18y included: people with a diagnosed eating disorder (ED as per DSM-5); endurance athletes (training/competing ≥ 5 h/week); or control subjects. Participants (n = 197) completed an online survey assessing orthorexia (eating habits questionnaire, EHQ), eating motivations (TEMS-B) and compulsive exercise (CET). RESULTS: ED had the highest orthorexia symptom severity (92.0 ± 3.02, n = 32), followed by athletes (76.2 ± 2.74, n = 54) and controls (71.0 ± 1.80, n = 111) (F (2) = 18.2, p < 0.001). A strong positive correlation existed between weight control motives and higher orthorexia symptom severity (r = 0.54, 95% CI [1.35, 2.36], p < 0.001), while a weak negative association existed between Hunger and Pleasure motives and higher orthorexia symptom severity (r = 0.23, 95% CI [- 2.24, - 0.34], p = 0.008; r = 0.26, 95% CI [- 2.11, - 0.47], p = 0.002, respectively). A moderate positive relationship was found between CET and orthorexia symptom severity (95% CI [1.52, 3.12], p < 0.001). CONCLUSION: Adults with ED history and endurance athletes have greater orthorexia symptom severity compared to control. Clinicians working with at-risk populations should screen patients and be aware of red-flags of orthorexic traits, desire to control weight, and compulsive exercise behavior. LEVEL OF EVIDENCE: III: Evidence obtained from cohort studies.

Association between dietary factors, symptoms, and psychological factors in adults with dyspepsia: A cross-sectional study.

BACKGROUND: Evidence-based dietary management approaches for symptoms of dyspepsia are lacking. This study aimed to compare dietary factors, symptoms, quality of life (QOL) and salivary cortisol in dyspepsia participants and healthy controls. METHODS: A cross-sectional survey was completed by adults with dyspepsia (n = 121) meeting Rome IV criteria and healthy controls (n = 52). Outcome measures included self-reported questionnaires about dietary habits, triggers, restrictions, dietary management approaches, nutritional intake, psychological variables, QOL, gastrointestinal symptoms, and optional cortisol awakening response (CAR) via saliva samples. Data were analyzed using Chi-square or Mann-Whitney U. Cortisol awakening response data was analyzed using moderated regression controlling for age, gender and distress. KEY RESULTS: Fermentable carbohydrates (FODMAPs) (55%) were the most reported trigger in adults with dyspepsia. The dyspepsia group (88%) followed special diets more than controls (47%; p < 0.001), with a low FODMAP diet being most common (69%). The dyspepsia group consumed less fiber (p = 0.014), calcium (p = 0.015), and total FODMAPs (p < 0.001) than controls. There was a greater prevalence of comorbid anxiety (41%) and depression (31%) in dyspepsia compared to controls (15% and 12%, respectively, p < 0.001 and p = 0.006). The dyspepsia group had poorer QOL and greater gastrointestinal symptom severity than controls (p < 0.001). There was a negative association between anxiety and CAR (p = 0.001) in dyspepsia but not in controls. CONCLUSIONS & INFERENCES: Adults with dyspepsia follow special diets more than controls and perceive FODMAPs as a key dietary trigger. These findings highlight the importance of monitoring nutritional adequacy and QOL, and emphasize mechanisms of depleted stress response in dyspepsia, warranting further exploration.

Conference on 'Sustainable nutrition for a healthy life'.

Nutrition scientists are currently facing a substantial challenge: to feed the world population sustainably and ethically while supporting the health of all individuals, animals and the environment. The Nutrition Society of Australia's 2022 Annual Scientific meeting theme 'Sustainable nutrition for a healthy life' was a timely conference focusing on the environmental impact of global, national and local food systems, how nutrition science can promote sustainable eating practices while respecting cultural and culinary diversity and how to ensure optimal nutrition throughout life to prevent and manage chronic diseases. Comprehensive, diverse, collaborative and forward-thinking research was presented in a 3 d programme of keynote presentations, oral and poster sessions, breakfast and lunch symposiums, ending with a panel discussion to answer the question of how we can best achieve a nutritious food supply that supports human and planetary health. We concluded that this complex issue necessitates coordinated efforts and multi-faceted responses at local, national and global levels. Collaboration among consumers, scientists, industry and government using a systems approach is vital for finding solutions to this challenge.

The Effect of Gut-Training and Feeding-Challenge on Markers of Gastrointestinal Status in Response to Endurance Exercise: A Systematic Literature Review.

BACKGROUND: Nutrition during exercise is vital in sustaining prolonged activity and enhancing athletic performance; however, exercise-induced gastrointestinal syndrome (EIGS) and exercise-associated gastrointestinal symptoms (Ex-GIS) are common issues among endurance athletes. Despite this, there has been no systematic assessment of existing trials that examine the impact of repetitive exposure of the gastrointestinal tract to nutrients before and/or during exercise on gastrointestinal integrity, function, and/or symptoms. OBJECTIVE: This systematic literature review aimed to identify and synthesize research that has investigated the impact of 'gut-training' or 'feeding-challenge' before and/or during exercise on markers of gastrointestinal integrity, function, and symptoms. METHODS: Five databases (Ovid MEDLINE, EMBASE, CINAHL Plus, Web of Science Core Collection, and SPORTDiscus) were searched for literature that focused on gut-training or feeding-challenge before and/or during exercise that included EIGS and Ex-GIS variables. Quality assessment was conducted in duplicate and independently using the Cochrane Collaboration's risk-of-bias (RoB 2) tool. RESULTS: Overall, 304 studies were identified, and eight studies were included after screening. Gut-training or feeding-challenge interventions included provision of carbohydrates only (n = 7) in various forms (e.g., gels or liquid solutions) during cycling or running, or carbohydrate with protein (n = 1) during intermittent exercise, over a varied duration (4-28 days). Gut discomfort decreased by an average of 47% and 26% with a 2-week repetitive carbohydrate feeding protocol (n = 2) and through repeated fluid ingestion over five trials (n = 1), respectively. Repetitive carbohydrate feeding during exercise for 2 weeks resulted in the reduction of carbohydrate malabsorption by 45-54% (n = 2), but also led to no significant change (n = 1). The effect of gut-training and feeding-challenges on the incidence and severity of Ex-GIS were assessed using different tools (n = 6). Significant improvements in total, upper, and lower gastrointestinal symptoms were observed (n = 2), as well as unclear results (n = 4). No significant changes in gastric emptying rate (n = 2), or markers of intestinal injury and permeability were found (n = 3). Inconclusive results were found in studies that investigated plasma inflammatory cytokine concentration in response to exercise with increased carbohydrate feeding (n = 2). CONCLUSIONS: Overall, gut-training or feeding-challenge around exercise may provide advantages in reducing gut discomfort, and potentially improve carbohydrate malabsorption and Ex-GIS, which may have exercise performance implications.

The effect of gastrointestinal bitter sensing on appetite regulation and energy intake: A systematic review.

Taste receptors are located on the epithelial surface throughout the alimentary canal to identify nutrients and potential toxins. In the oral cavity, the role of taste is to encourage or discourage ingestion, while in the gastrointestinal (GI) tract, the taste receptors help the body prepare for an appropriate response to the ingested foods. The GI sensing of bitter compounds may alter the secretion of appetite-related hormones thereby reducing food intake, which may have potential use for managing health outcomes. This systematic literature review investigated the acute effects of administering different bitter tasting compounds on circulating levels of selected GI hormones, subjective appetite, and energy intake in humans. A literature search was conducted using Medline, CINAHL and Web of Science databases. Of 290 articles identified, 16 met the inclusion criteria. Twelve studies assessed food intake; four of these found bitter administration decreased food intake and eight did not. Fourteen studies assessed subjective appetite; seven found bitter administration affected at least one measure of appetite and seven detected no significant changes. Nine studies included measures of GI hormones; no significant effects were found for changes in GLP-1, CCK or PYY. Four studies measured motilin and ghrelin and found mostly consistent changes in either food intake or subjective appetite. Overall, the data on food intake and subjective appetite were inconsistent, with only motilin and ghrelin responsive to post-oral bitter administration. There is limited consistent conclusive evidence that bitter compounds influence food intake, appetite or hormones with the reasons for this discussed within. SYSTEMATIC REVIEW REGISTRATION: CRD42021226102.

Review article: exclude or expose? The paradox of conceptually opposite treatments for irritable bowel syndrome.

BACKGROUND: Irritable bowel syndrome (IBS) is a heterogeneous disorder of gut-brain interaction (DGBI) maintained by interacting biological, psychological, and social processes. Interestingly, there are two contrasting yet evidence-based treatment approaches for reducing IBS symptoms: exclusion diets such as those low in fermentable oligo-, di-, monosaccharides and polyols (FODMAPs) and exposure-based cognitive-behavioural therapy (CBT). Exclusion diets recommend patients avoid foods thought to be symptom-inducing, whereas exposure-based CBT encourages patients to expose themselves to foods. AIMS: To address the paradox of conceptually opposite exclusion diets and exposure-based CBT for IBS. METHODS: In this conceptual review, we describe the rationale, practical implementation, evidence base and strengths and weaknesses of each treatment. We conducted up-to-date literature search concerning the low FODMAP diet and CBT, and performed a secondary analysis of a previously conducted trial to illustrate a key point in our review. RESULTS: The low FODMAP diet has demonstrated efficacy, but problems with adherence, nutritional compromise, and heightened gastrointestinal-specific anxiety raise caution. Exposure-based CBT has demonstrated efficacy with substantial evidence for gastrointestinal-specific anxiety as a key mechanism of action. Mediation analysis also showed that increased FODMAP intake mediated decreased symptom severity in exposure-based CBT. However, there is minimal evidence supporting which treatment "works best for whom" and how these approaches could be best integrated. CONCLUSIONS: Even though exclusion diets and exposure-based CBT are conceptually opposite, they each have proven efficacy. Clinicians should familiarise themselves with both treatments. Further research is needed on predictors, mechanisms and moderators of treatment outcomes.

Orthorexia nervosa is a concern in gastroenterology: A scoping review.

There is concern that use of restrictive therapeutic diets, such as those used in disorders of the gut-brain interaction (DGBI), may increase disordered eating. In this issue of Neurogastroenterology and Motility, Burton Murray et al. and Peters et al. both demonstrate a high prevalence of disordered eating in patients with gastrointestinal conditions, particularly those with DGBI. Given these findings, it is likely that orthorexia is common in this patient group, although this was not directly examined in these studies. Orthorexia nervosa is described as an obsessive and unsafe focus on eating foods perceived as healthy. This mini-review therefore focuses on orthorexia by conducting a scoping review, as per the PRISMA extension for scoping reviews, aimed to assess the prevalence of orthorexia, and associations between orthorexia and restrictive eating practices. While a wide range of orthorexia prevalence has been reported (0%-97%) across the 57 studies included, no studies assessed prevalence specifically in gastrointestinal conditions. Four of eight studies describing diseases associated with specific dietary patterns suggested that participants who followed a diet for "digestive issues" or "food intolerances" were at higher orthorexia risk. These results suggest that dietary modifications may be a factor contributing to orthorexia. Additionally, we provide a commentary on the clinical implications of the findings for gastrointestinal conditions including a clinical flow chart. Clinicians should consider if a restrictive diet is appropriate for individuals with DGBI and include screening for disordered eating prior to implementation of dietary modifications. Future prospective studies should evaluate orthorexia within this patient group.

How to Implement the 3-Phase FODMAP Diet Into Gastroenterological Practice.

Background/Aims: The 3-phase fermentable oligo-, di-, mono-saccharides, and polyols (FODMAP) diet has shown a high level of efficacy in irritable bowel syndrome, largely based on dietitian delivered education. However, access to dietitians can be limited, and challenges exist when applying the diet to a wide range of cultures, such as limited FODMAP analysis of local foods. This review aims to discuss ways to optimally use the FODMAP diet in practice in a wide range of cultures, directed at gastroenterologists from a dietitian's perspective. Methods: Recent literature was analysed via search databases including Medline, CINAHL, PubMed and Scopus. Results: The dietetic process involves detailed assessment and follow-up through the 3 stages of the FODMAP diet (restriction, re-introduction, and long-term maintenance). Emerging evidence suggests the diet can be delivered by other health professionals such as the gastroenterologist or nurse, but training on how to do so successfully would be needed. Self-guided approaches through use of technology or specialised food delivery services may be an alternative when dietitians are not available, but efficacy data is limited. Regardless of delivery mode, nutritional and psychological risks of the diet must be mitigated. Additionally, culturally appropriate education must be provided, with accommodations necessary when the FODMAP content of local foods are unknown. Conclusion: While the diet has shown improved irritable bowel syndrome outcomes across studies, it is important to acknowledge the essential role of dietitians in implementing, tailoring, and managing the diet to achieve the best outcome for each individual.

Assessing the effectiveness of a 4-week online intervention on food literacy and fruit and vegetable consumption in Australian adults: The online MedDiet challenge.

Australians fail to meet the daily recommended two and five serves of fruit and vegetable respectively, which increases mortality risk for non-communicable diseases such as cardiovascular disease and type 2 diabetes. This study aimed to evaluate the effectiveness of an online intervention delivered through social media on food literacy and fruit and vegetable consumption in Australian adults. In a pre-post single group experimental study, 29 participants completed the "online MedDiet challenge", a four-week intervention delivered via Facebook. Infographics, recipes and informational videos aligned with food literacy concepts related to the Mediterranean Diet were shared with participants. Outcome measures included a validated food literacy questionnaire with two questions from the National Nutrition Survey to record fruit and vegetable consumption. The mean age of participants was 52 years (range: 25-67 years). Post intervention, food literacy improved between 21%-45% across each survey component. Participants also reported an increase in fruit and vegetable consumption by 0.6 and 1.3 serves per day (p < 0.05) respectively. Social media holds potential for increasing fruit and vegetable consumption in adults through food literacy. Future research should focus on longer studies and larger cohorts to confirm that food literacy plays a key component to maintain sustainability of such interventions.

The lived experience of irritable bowel syndrome: A focus on dietary management.

BACKGROUND: Irritable bowel syndrome (IBS) is a disorder of the gut-brain axis with a prevalence of 3.5% in Australia. The complexity of mechanisms underlying IBS means patients often respond poorly to treatment. There is encouraging evidence for the successful use of dietary strategies for short- and long-term management of IBS. OBJECTIVE: The aim of this narrative review was to explore the lived experience of IBS from the patient perspective with emphasis on dietary involvement and diet management of the condition. DISCUSSION: There are a number of dietary constituents implicated in IBS, and patients' main concerns are the trial-and-error nature of identifying triggers, uncertainty regarding food choices and reduced enjoyment of food. Despite this, dietary modifications are accepted by patients and healthcare professionals (HCPs) as an efficacious management strategy. A meaningful relationship with their HCP can improve patient adherence, treatment success and overall satisfaction for patients.

Diet or medication in primary care patients with IBS: the DOMINO study - a randomised trial supported by the Belgian Health Care Knowledge Centre (KCE Trials Programme) and the Rome Foundation Research Institute.

BACKGROUND: In Europe, IBS is commonly treated with musculotropic spasmolytics (eg, otilonium bromide, OB). In tertiary care, a low fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAP) diet provides significant improvement. Yet, dietary treatment remains to be explored in primary care. We evaluated the effect of a smartphone FODMAP-lowering diet application versus OB on symptoms in primary care IBS. METHODS: IBS patients, recruited by primary care physicians, were randomised to 8 weeks of OB (40 mg three times a day) or diet and followed for 24 weeks. We compared IBS Symptom Severity Score and the proportion of responders (improvement ≥50 points) in all patients and the subgroup fulfilling Rome IV criteria (Rome+). We also evaluated treatment efficacy, quality of life, anxiety, depression, somatic symptom severity (Patient Health Questionnaire (PHQ15, PHQ9)) and treatment adherence and analysed predictors of response. RESULTS: 459 primary care IBS patients (41±15 years, 76% female, 70% Rome+) were randomised. The responder rate after 8 weeks was significantly higher with diet compared with OB (71% (155/218) vs 61% (133/217), p=0.03) and more pronounced in Rome+ (77% (118/153) vs 62% (98/158), p=0.004). Patients allocated to diet (199/212) were 94% adherent compared with 73% with OB (148/202) (p<0.001). The significantly higher response rate with diet was already observed after 4 weeks (62% (132/213) vs 51% (110/215), p=0.02) and a high symptom response persisted during follow-up. Predictors of response were female gender (OR=2.08, p=0.04) for diet and PHQ15 (OR=1.10, p=0.02) for OB. CONCLUSION: In primary care IBS patients, a FODMAP-lowering diet application was superior to a spasmolytic agent in improving IBS symptoms. A FODMAP-lowering diet should be considered the first-line treatment for IBS in primary care. TRIAL REGISTRATION NUMBER: NCT04270487.

Low FODMAP diet beyond IBS: Evidence for use in other conditions.

The low FODMAP diet has shifted therapeutic guidelines for symptom management in irritable bowel syndrome. Given FODMAPs are involved in underlying pathological mechanisms of visceral hypersensitivity, research groups are exploring the use of the low-FODMAP diet as a potential management approach in several conditions outside of irritable bowel syndrome. Early data shows promise for functional dyspepsia, improving epigastric symptoms, and although evidence is scant, the diet has been proposed to assist in small intestinal bacterial overgrowth. Characterisation of sucrase-isomaltase deficiency may offer profiling for predicting response to the diet. Although encouraging, carefully controlled broader trials are needed across the conditions discussed to completely understand the effects of the low FODMAP diet on symptoms, safety, and efficacy in clinical practice.

An exploratory study of industry perspectives to inform undergraduate nutrition employability initiatives.

AIM: The aim of this study was to explore nutrition professionals' perspectives of nutrition graduates' employability skills, and knowledge and skills required in the industry to understand gaps in undergraduate nutrition curriculum. METHODS: Nutrition professionals (n = 26) across Australia were approached to participate in semi-structured interviews via telephone in 2018. Interviews were transcribed verbatim, data analysed using thematic analysis, and results interpreted and discussed. RESULTS: Nine participants across six work environments completed interviews. Common work roles were identified in their diverse areas of practice: nutrition educators, food developers, team members, and business leaders. Nutrition professionals identified that, in addition to evidence-based discipline knowledge, key skills and knowledge needed for their roles were interpersonal communication, including writing and listening. Participants highlighted the need for employability skills to be embedded within curriculum with emphasis on professional skills, business skills and discipline-specific skills in communicating complex science messages to a range of audiences. Networking, and formal and informal work-integrated learning were viewed as important vehicles for developing required skills. Participants expected that universities develop curriculum to address gaps; however, reflection by the academic researchers suggested this should be a joint role. CONCLUSIONS: Early career planning, professional skill development, work experience and networking opportunities should enhance graduate employability.

Gut-brain axis dysfunction underlies FODMAP-induced symptom generation in irritable bowel syndrome.

BACKGROUND: FODMAPs produce similar small bowel water and colonic gas in patients with irritable bowel syndrome (IBS) and healthy controls (HCs), despite IBS patients reporting increased gastrointestinal (GI) symptoms. AIM: To unravel the mechanisms underlying FODMAP-induced symptom reporting, we investigated gut and brain responses to fructan administration in IBS patients and HC. METHODS: This randomised, double-blind, cross-over study consisted of three visits where fructans (40 g/500 mL saline), glucose (40 g/500 mL saline) or saline (500 mL) were infused intragastrically during 1 h MR brain scanning; abdominal MRI was performed before, 1 h, and 2 h post-infusion. Symptoms were rated using validated scales. RESULTS: In IBS (n = 13), fructans induced more cramps, pain, flatulence and nausea compared to glucose (P = 0.03, 0.001, 0.009 and <0.001 respectively), contrary to HC (n = 13) (all P > 0.14), with between-group differences for cramps and nausea (P = 0.004 and 0.023). Fructans increased small bowel motility and ascending colonic gas and volume equally in IBS and HC (between-group P > 0.25). The difference in colonic gas between fructans and saline covaried with differences in bloating and cramps in IBS (P = 0.008 and 0.035 respectively). Pain-related brain regions responded differentially to fructans in IBS compared to HC, including the cerebellum, supramarginal gyrus, anterior and midcingulate cortex, insula and thalamus (pFWE-corrected  < 0.05); these brain responses covaried with symptom responses in IBS. CONCLUSIONS: Fructans increase small bowel motility and colon gas and volume similarly in IBS patients and HC. Increased symptom responses to fructans in IBS covary with altered brain responses in pain-related regions, indicating that gut-brain axis dysregulation may drive FODMAP-induced symptom generation in IBS.

Intragastric fructose administration interacts with emotional state in homeostatic and hedonic brain regions.

Background: Interoceptive properties of food may influence emotional state and its neural basis, as shown for fatty acids but remains unstudied for carbohydrates.Objectives: To study the effects of fructose and its interaction with sad emotion on brain activity in homeostatic and hedonic regions and investigate whether gut hormone responses can explain effects.Design: In 15 healthy subjects, brain activity for 40min after intragastric infusion of fructose (25g) or water was recorded using a cross-over pharmacological magnetic resonance imaging (phMRI) paradigm. Sad or neutral emotional states were induced by classical music and emotional facial expressions. Emotional state was assessed using the Self-Assessment Manikin. Blood samples were taken to assess gut hormone levels. Brain responses to fructose versus placebo, sad versus neutral emotion, and their interaction were analyzed over time in a single mask of a priori defined regions of interest at a voxel-level threshold of pFWEcorrected <0.05. Effects on emotion and hormones were tested using linear mixed models.Results: No main effects of fructose, emotion, or fructose-by-emotion interaction on emotional ratings were observed. Main effects of fructose, emotion and aninteraction effect were found on brain activity (medulla, midbrain, hypothalamus, basal ganglia, anterior insula, orbitofrontal cortex, anterior cingulate cortex and amygdala). An increase in circulating GLP-1 after fructose in neutral emotion was abolished during sad emotion (fructose-by-emotion-by-time, p=0.041). Ghrelin levels were higher in sad emotion (time-by-emotion, p=0.037).Conclusions: Emotional state interacts with brain and endocrine responses to intragastric infusion of 25 g of fructose, however such an effect was not found at behavioral level.Trial registration: ClinicalTrials.gov identifier: NCT02946983.

Effect of Gluten Ingestion and FODMAP Restriction on Intestinal Epithelial Integrity in Patients with Irritable Bowel Syndrome and Self-Reported Non-Coeliac Gluten Sensitivity.

SCOPE: Since epithelial barrier dysfunction has been associated with gluten and fermentable oligosaccharide, disaccharide, monosaccharide, and polyols (FODMAPs), the effect of alterations in FODMAP a gluten intake on epithelial barrier function in patients with irritable bowel syndrome (IBS) who self-reported gluten sensitivity. METHODS AND RESULTS: Circulating concentrations of markers of epithelial injury (syndecan-1 and intestinal fatty acid-binding protein) and bacterial translocation (lipopolysaccharide-binding protein and soluble CD14) are measured while consuming habitual gluten-free diet and during blinded challenges with gluten or placebo on a background of low FODMAP intake. In 33 patients, only syndecan-1 concentrations during their habitual diet are elevated (median 43 ng mL-1 ) compared with 23 ng mL-1 in 49 healthy subjects (p < 0.001). On a low FODMAP diet, symptoms are reduced and levels of syndecan-1 (but not other markers) fell by a median 3335% (p < 0.001) irrespective of whether gluten is present or not. CONCLUSION: Gluten ingestion has no specific effect on epithelial integrity or symptoms in this cohort, but reducing FODMAP intake concomitantly reduces symptoms and reverses apparent colonic epithelial injury. These findings highlight the heterogeneity of populations self-reporting gluten sensitivity and implicate FODMAPs in colonic injury in IBS.