Non-coeliac gluten sensitivity: piecing the puzzle together

Gluten-free Diet, a Friend or a Foe, an American Perspective

Gluten proteins in cereal grains are often considered unsafe for health. Indeed, the dissemination of misinformation through various sources has led to a widespread misconception that the consumption of gluten by healthy individuals results in adverse health consequences and contributes to obesity. In recent years, many health-conscious consumers have started reducing or avoiding gluten consumption without a medical recommendation. Consequently, the adoption of gluten-free diets has expanded significantly. This study compared 39 gluten-free products and their gluten-containing counterparts for energy, sugar, dietary fiber content, and price. We found that, on average, gluten-free products available to United States consumers contained significantly less protein and more sugar and calories. Furthermore, on average, gluten-free products are more expensive than gluten-containing products. Our finding may serve as a guide for dietitians, nutritionists, and legislators in introducing a gluten-free prescription list for individuals with celiac disease, wheat allergy, and non-celiac wheat sensitivity.

Sorghum (Sorghum vulgare): an ancient grain, a novel choice for a healthy gluten-free diet

Celiac disease (CD) is an autoimmune disease related to gluten consumption. To date, the only effective therapy that can reverse symptoms and prevent complications is the gluten-free diet (GFD), which is challenging to maintain and has potential health risks. Identifying foods that can help diversify the GFD and that best match the nutritional needs of people with CD may improve the health and quality of life of celiac patients. This review, conducted through a non-systematic search of the available literature, aims to gather the most recent research on nutritional issues in CD and GFD. Moreover, it highlights how sorghum characteristics could provide health benefits to CD patients that counteract the nutritional problems due to CD and the nutritional consequences of GFD acceptance. Sorghum contains a wide variety of bioactive compounds, such as flavones and tannins, that have shown anti-inflammatory activity in preclinical studies. They can also regulate blood sugar levels and lower cholesterol to reduce the effects of common chronic diseases such as metabolic and cardiovascular diseases. Because it is gluten-free, its use in making foods for celiac patients is increasing, especially in the United States. In conclusion, sorghum is a fascinating grain with nutritional properties and health benefits for supplementing GFD. However, only one study confirms the short-term safety of sorghum inclusion in the GFD, and further long-term studies with a large sample are needed.

Sieving out non-celiac gluten sensitivity amongst patients with irritable bowel syndrome

OBJECTIVES

It is challenging to make diagnosis of non-celiac gluten sensitivity/non-celiac wheat sensitivity (NCGS/NCWS) in clinical practice, since there is no biomarker and diagnosis is based on response to gluten-free-diet (GFD). We used anti-gliadin antibody (AGA) for screening patients with IBS for gluten-sensitivity.

METHODS

492 Adult-patients with IBS underwent screening for celiac disease and gluten-sensitivity using IgA anti-tissue transglutaminase antibody and IgA-AGA and IgG-AGA, respectively. Patients with positive AGA (IgA and/or IgG) were invited to follow GFD, those willing were put on GFD for 6-weeks. Responsive patients were given gluten re-challenge. Diagnosis of NCGS was confirmed if they had recurrence of symptoms.

RESULTS

Of 492 patients with IBS, AGA was positive in 61(12.4 %), hence suspected to have gluten-sensitivity. Of 31 who agreed to participate and followed GFD for 6-weeks, 17 (54.8 %) had complete (>30 % improvement) and 10(32.2 %) had partial (>20 % improvement) response. All 17 complete-responders were given gluten re-challenge for 6-weeks, symptoms recurred in all and hence were confirmed to have NCGS/NCWS. Significant decrease in AGA levels occurred almost in all GFD-responders.

CONCLUSIONS

12.4 % IBS patients have biological evidence of gluten/wheat-sensitivity. Almost 87 % patients with IBS having AGA responded to GFD. The value of AGA may further be explored as a biomarker for screening for the presence of NCGS, before recommending this test for the clinical practice.

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

INTRODUCTION

There is large variation in response to diet in irritable bowel syndrome (IBS) and determinants for differential response are poorly understood.

OBJECTIVES

Our 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.

METHODS

Data 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.

RESULTS

Regression 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.

CONCLUSION

Differential 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.

IBS randomized study: FODMAPs alter bile acids, phenolic- and tryptophan metabolites, while gluten modifies lipids

Diet is considered a culprit for symptoms in irritable bowel syndrome (IBS), although the mechanistic understanding of underlying causes is lacking. Metabolomics, i.e., the analysis of metabolites in biological samples may offer a diet-responsive fingerprint for IBS. Our aim was to explore alterations in the plasma metabolome after interventions with fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPs) or gluten versus control in IBS, and to relate such alterations to symptoms. People with IBS (n = 110) were included in a double-blind, randomized, crossover study with 1-wk provocations of FODMAPs, gluten, or placebo. Symptoms were evaluated with the IBS severity scoring system (IBS-SSS). Untargeted metabolomics was performed on plasma samples using LC-qTOF-MS. Discovery of metabolite alterations by treatment was performed using random forest followed by linear mixed modeling. Associations were studied using Spearman correlation. The metabolome was affected by FODMAP [classification rate (CR) 0.88, P < 0.0001], but less by gluten intake CR 0.72, P = 0.01). FODMAP lowered bile acids, whereas phenolic-derived metabolites and 3-indolepropionic acid (IPA) were higher compared with placebo. IPA and some unidentified metabolites correlated weakly to abdominal pain and quality of life. Gluten affected lipid metabolism weakly, but with no interpretable relationship to IBS. FODMAP affected gut microbial-derived metabolites relating to positive health outcomes. IPA and unknown metabolites correlated weakly to IBS severity. Minor symptom worsening by FODMAP intake must be weighed against general positive health aspects of FODMAP. The gluten intervention affected lipid metabolism weakly with no interpretable association to IBS severity. Registration: www.clinicaltrials.gov as NCT03653689.NEW & NOTEWORTHY In irritable bowel syndrome (IBS), fermentable oligo-, di-, monosaccharides, and polyols (FODMAPs) affected microbial-derived metabolites relating to positive health outcomes such as reduced risk of colon cancer, inflammation, and type 2 diabetes, as shown in previous studies. The minor IBS symptom induction by FODMAP intake must be weighed against the positive health aspects of FODMAP consumption. Gluten affected lipids weakly with no association to IBS severity.

Does a Gluten-Free Diet Improve Quality of Life and Sleep in Patients with Non-Coeliac Gluten/Wheat Sensitivity?

INTRODUCTION

The role of a gluten-free diet (GFD) in Non-Coeliac Gluten/Wheat Sensitivity (NCGWS) is unclear. We present the largest study comparing adherence to a GFD in patients with Coeliac Disease (CD) and NCGWS and assess its impact on quality of life (QoL) and sleep in patients with NCGWS.

METHODS

Patients with NCGWS at a tertiary centre completed the Coeliac Disease Adherence Test (CDAT), Coeliac Symptom Index (CSI) and Sleep Condition Indicator (SCI). Higher CDAT scores indicate worse adherence, higher CSI scores indicate poorer QoL, and higher SCI scores indicate better sleep. CDAT scores were correlated with CSI and SCI scores. A second group of patients with CD completed the CDAT questionnaire only. Results were compared with the CDAT responses from the NCGWS group.

RESULTS

For the NCGWS cohort (n = 125), the median CDAT score was 17/35, indicating poor adherence. The median CSI score was 44/80, with 40% of scores associated with a poor QoL. The median SCI score was 14/32, and DSM-V criteria for insomnia was met by 42% of patients. There was a positive correlation between CSI and CDAT scores (r = 0.59, p < 0.0001) and a negative correlation between SCI and CDAT scores (r = -0.37, p = 0.0002). In the CD cohort (n = 170), the median CDAT score was 13/35. Patients with NCGWS had poorer adherence compared to CD (CDAT: 17.0 vs. 13.0, respectively, p = 0.0001).

CONCLUSION

Patients with NCGWS adhere to a GFD less than those with CD. Poorer adherence to a GFD in patients with NCGWS correlates with a worse QoL and sleep performance.

Effects of FODMAPs and Gluten on Gut Microbiota and Their Association with the Metabolome in Irritable Bowel Syndrome: A Double-Blind, Randomized, Cross-Over Intervention Study

BACKGROUND

A mechanistic understanding of the effects of dietary treatment in irritable bowel syndrome (IBS) is lacking. Our aim was therefore to investigate how fermentable oligo- di-, monosaccharides, and polyols (FODMAPs) and gluten affected gut microbiota and circulating metabolite profiles, as well as to investigate potential links between gut microbiota, metabolites, and IBS symptoms.

METHODS

We used data from a double-blind, randomized, crossover study with week-long provocations of FODMAPs, gluten, and placebo in participants with IBS. To study the effects of the provocations on fecal microbiota, fecal and plasma short-chain fatty acids, the untargeted plasma metabolome, and IBS symptoms, we used Random Forest, linear mixed model and Spearman correlation analysis.

RESULTS

FODMAPs increased fecal saccharolytic bacteria, plasma phenolic-derived metabolites, 3-indolepropionate, and decreased isobutyrate and bile acids. Gluten decreased fecal isovalerate and altered carnitine derivatives, CoA, and fatty acids in plasma. For FODMAPs, modest correlations were observed between microbiota and phenolic-derived metabolites and 3-indolepropionate, previously associated with improved metabolic health, and reduced inflammation. Correlations between molecular data and IBS symptoms were weak.

CONCLUSIONS

FODMAPs, but not gluten, altered microbiota composition and correlated with phenolic-derived metabolites and 3-indolepropionate, with only weak associations with IBS symptoms. Thus, the minor effect of FODMAPs on IBS symptoms must be weighed against the effect on microbiota and metabolites related to positive health factors.

Diagnostic delay in adult coeliac disease: An Italian multicentre study

BACKGROUND

There are few data regarding the diagnostic delay and its predisposing factors in coeliac disease (CD).

AIMS

To investigate the overall, the patient-dependant, and the physician-dependant diagnostic delays in CD.

METHODS

CD adult patients were retrospectively enroled at 19 Italian CD outpatient clinics (2011-2021). Overall, patient-dependant, and physician-dependant diagnostic delays were assessed. Extreme diagnostic, i.e., lying above the third quartile of our population, was also analysed. Multivariable regression models for factors affecting the delay were fitted.

RESULTS

Overall, 2362 CD patients (median age at diagnosis 38 years, IQR 27-46; M:F ratio=1:3) were included. The median overall diagnostic delay was 8 months (IQR 5-14), while patient- and physician-dependant delays were 3 (IQR 2-6) and 4 (IQR 2-6) months, respectively. Previous misdiagnosis was associated with greater physician-dependant (1.076, p = 0.005) and overall (0.659, p = 0.001) diagnostic delays. Neurological symptoms (odds ratio 2.311, p = 0.005) and a previous misdiagnosis (coefficient 9.807, p = 0.000) were associated with a greater extreme physician-dependant delay. Gastrointestinal symptoms (OR 1.880, p = 0.004), neurological symptoms (OR 2.313, p = 0.042), and previous misdiagnosis (OR 4.265, p = 0.000) were associated with increased extreme overall diagnostic delay.

CONCLUSION

We identified some factors that hamper CD diagnosis. A proper screening strategy for CD should be implemented.

Feeding Our Microbiota: Stimulation of the Immune/Semiochemical System and the Potential Amelioration of Non-Communicable Diseases

Non-communicable diseases are those conditions to which causative infectious agents cannot readily be assigned. It is increasingly likely that at least some of these conditions are due to the breakdown of the previously mutualistic intestinal microbiota under the influence of a polluted, biocide-rich, environment. Following the mid-20th century African studies of Denis Burkitt, the environmental cause of conditions such as obesity has been ascribed to the absence of sufficient fibre in the modern diet, however in itself that is insufficient to explain the parallel rise of problems with both the immune system and of mental health. Conversely, Burkitt himself noted that the Maasai, a cattle herding people, remained healthy even with their relatively low intake of dietary fibre. Interestingly, however, Burkitt also emphasised that levels of non-communicable disease within a population rose as faecal weight decreased significantly, to about one third of the levels found in healthy populations. Accordingly, a more cogent explanation for all the available facts is that the fully functioning, adequately diverse microbiome, communicating through what has been termed the microbiota-gut-brain axis, helps to control the passage of food through the digestive tract to provide itself with the nutrition it needs. The method of communication is via the production of semiochemicals, interkingdom signalling molecules, potentially including dopamine. In turn, the microbiome aids the immune system of both adult and, most importantly, the neonate. In this article we consider the role of probiotics and prebiotics, including fermented foods and dietary fibre, in the stimulation of the immune system and of semiochemical production in the gut lumen. Finally, we reprise our suggestion of an ingestible sensor, calibrated to the detection of such semiochemicals, to assess both the effectiveness of individual microbiomes and methods of amelioration of the associated non-communicable diseases.

Gluten-free foods: a 'health halo' too far for oral health?

Background Over the past decade, the rise of consumers following a gluten-free diet has increased greatly. The majority of people following a gluten-free diet have not been diagnosed with coeliac disease or gluten or wheat intolerance but believe it to be a health benefit.Aim To assess the differences between gluten-free and gluten-containing products with regards to the implications this might have on oral (and wider) health.Method In total, 50 purposively selected products (25 gluten-free and gluten-containing pairs) available to UK consumers, classified using the UK National Diet and Nutrition Survey food categories, were analysed using content analysis of food packaging. The European Union front-of-pack labelling system revealed the nutritional composition of each product, focusing on carbohydrates, sugars and energy. Cost and use of emotive language to market products was also assessed.Results A nutritional comparison of the 25 product pairings found that, on average, all gluten-free products contained more calories, total carbohydrates and total sugar. The majority of the gluten-free products were classified as 'confectionary' or 'baked goods,' emphasising that products primarily consisted of foods high in sugar. The average sugar per 100 g for each category of food ranged from 2.5-37.0 g/100 g (gluten-free) compared to 2.1-30 g/100 g (gluten-containing). All gluten-free products were considerably more expensive when compared with the conventional version; the average price difference ranged from £0.08 to £4.40.Conclusion This study emphasises the 'health halo' phenomena, where foods for special diets are regarded by consumers as healthy when in fact they are not. This results partly from the products being mainly high-sugar 'treats', which are not a core of the UK Eatwell Guide food-based dietary guidelines. As many people consuming gluten-free products in the UK do not need them from a medical perspective, this could have implications for oral and wider health. It is important that members of the dental team are aware of the possible implications of a gluten-free diet where it is not medically indicated, coupled with reliance on convenience foods.

Microbiome–Gut Dissociation in the Neonate: Obesity and Coeliac Disease as Examples of Microbiome Function Deficiency Disorder

The purpose of this article is to provide a direction for translational research based on an analysis of the nature of complex, immune-related conditions such as obesity and coeliac disease. In essence, it seems that the prevalence of these non-communicable diseases is related to the degradation of the microbiome during the industrialisation of society, and that their nature can be used to infer the functions of the “pre-industrial” microbiome. Based on this analysis, the key point is the necessity for the fully functioning microbiome, acting alongside the parental genetic inheritance of the child, to be in place immediately after birth. In our view, this is achieved by the seemingly accidental process of maternal microbial inheritance during normal birth. Note, however, that this is not possible if the microbiome of the mother is itself degraded following previous problems. Under these conditions the health of a child may be affected from the moment of birth, although, with the exception of atopic diseases, such as eczema and food allergy, the consequences may not become apparent until late childhood or as an adult. In this way, this microbiome function deficiency hypothesis incorporates the epidemiological observations of David Strachan and David Barker in that their onset can be traced to early childhood. Coeliac disease has been chosen as an illustrative example of a multifactorial disorder due to the fact that, in addition to a series of immune system manifestations and a potential problem with food absorption, there is also a significant psychological component. Finally, it is worth noting that an ingestible sensor calibrated to the detection of interkingdom communication molecules (semiochemicals) within the intestine may offer a practical way of assessment and, perhaps, amelioration of at least some of the consequences of non-communicable disease.

Gluten-free diet adherence and implications for the diagnosis of coeliac disease

Coeliac disease (CD) is an autoimmune disorder caused by the ingestion of gluten containing foods in genetically susceptible individuals, with a worldwide prevalence of up to 1%. Currently, the only available treatment is a gluten-free diet (GFD). Screening for CD is primarily performed using serum based testing for anti-tissue transglutaminase (tTG) antibodies. Patients must be on a gluten containing diet at the time of testing to ensure an accurate serological result. We investigated the prevalence of a GFD in hospital clinic settings and the general population using survey data to estimate the proportion of CD patients that may be misdiagnosed for CD based on serological tests. Data were collected at clinics of a metropolitan hospital in Sydney, Australia, and the general population. Data from Medicare Benefits Scheme and tTG results from a large Australian private laboratory were reviewed for comparison. Of 778 participants who responded to the survey, 58 (7.5%) were on a GFD. More patients attending the immunology (15.9%) and gastroenterology (12.1%) clinics adopted a GFD than those attending the diabetes (2.6%) or endocrinology (6.1%) clinics, or in the general population (4.3%). More females than males excluded gluten from their diet (p<0.0001). Medicare statistics between 2013 and 2019 demonstrated an increase in CD serological testing; however, tTG data from a private pathology highlighted a stable level of elevated tTG antibodies of 3% of total tests performed. The high number of individuals on a GFD is likely impacting the ability to accurately diagnose CD using serum-based testing.

Fermentable oligo-, di-, monosaccharides, and polyols (FODMAPs), but not gluten, elicit modest symptoms of irritable bowel syndrome: a double-blind, placebo-controlled, randomized three-way crossover trial

BACKGROUND

Irritable bowel syndrome (IBS) has been associated with diets rich in fermentable oligo-, di-, monosaccharides, and polyols (FODMAPs), and gluten. Most previous studies have been single-blind and have focused on the elimination of FODMAPs or provocation with single FODMAPs. The effect of gluten is unclear, large trials isolating the effect of gluten from that of FODMAPs are needed.

OBJECTIVES

The aims of this study were to ensure high intakes of a wide range of FODMAPs, gluten, or placebo, and to evaluate the effects on IBS symptoms using the IBS-severity scoring system (IBS-SSS).

METHODS

The study was carried out with a double-blind, placebo-controlled, randomized 3-way crossover design in a clinical facility in Uppsala from September 2018 to June 2019. In all, 110 participants fulfilling the IBS Rome IV criteria, with moderate to severe IBS, were randomly assigned; 103 (90 female, 13 male) completed the trial. Throughout, IBS participants maintained a diet with minimal FODMAP content and no gluten. Participants were block-randomly assigned to 1-wk interventions with FODMAPs (50 g/d), gluten (17.3 g/d), or placebo, separated by 1-wk washout. All participants who completed ≥1 intervention were included in the intention-to-treat analysis.

RESULTS

In participants with IBS (n = 103), FODMAPs caused higher IBS-SSS scores (mean 240 [95% CI: 222, 257]) than placebo (198 [180, 215]; P = 0.00056) or gluten (208 [190, 226]; P = 0.013); no differences were found between the placebo and gluten groups (P = 1.0). There were large interindividual differences in IBS-SSS scores associated with treatment. No adverse events were reported.

CONCLUSION

In participants with IBS, FODMAPs had a modest effect on typical IBS symptoms, whereas gluten had no effect. The large interindividual differences in responses to the interventions warrant further detailed studies to identify possible underlying causes and enable individual prediction of responses. This trial was registered at www.clinicaltrials.gov as NCT03653689.

High Protein Substitutes for Gluten in Gluten-Free Bread

Gluten-free products have come into the market in order to alleviate health problems such as celiac disease. In this review, recent advances in gluten-free bread are described along with plant-based gluten-free proteins. A comparison with animal-based gluten-free proteins is made reporting on different high protein sources of animal origin. Sea microorganisms- and insect-based proteins are also mentioned, and the optimization of the structure of gluten-free bread with added high protein sources is highlighted along with protein digestibility issues. The latter is an issue for consideration that can be manipulated by a careful design of the mixture in terms of phenolic compounds, soluble carbohydrates and fibres, but also the baking process itself. Additionally, the presence of enzymes and different hydrocolloids are key factors controlling quality features of the final product.

Intestinal Exposure to Food-Derived Protease Inhibitors: Digestion Physiology- and Gut Health-Related Effects

Plant-derived protease inhibitors (PI), such as Bowman-Birk inhibitors and Kunitz-type inhibitors, have been suggested to negatively affect dietary protein digestion by blocking the activity of trypsin and chymotrypsin in the human gastrointestinal system. In addition, some PIs may possess proinflammatory activities. However, there is also scientific evidence on some beneficial effects of PIs, for example, gut-related anti-inflammatory and chemopreventive activities in vitro and in vivo. Some PIs are sensitive to processing and digestion; thus, their survival is an important aspect when considering their positive and negative bioactivities. The aim of this review was to evaluate the relevance of PIs in protein digestion in humans and to discuss the potential of PIs from whole foods and as purified compounds in decreasing symptoms of bowel-related conditions. Based on the reviewed literature, we concluded that while the complex interactions affecting plant protein digestibility and bioavailability remain unclear, PI supplements could be considered for targeted purposes to mitigate inflammation and gastric pain.

Whether a Gluten-Free Diet Should Be Recommended in Chronic Autoimmune Thyroiditis or Not?-A 12-Month Follow-Up

Elimination diets have recently become extremely popular among people with autoimmune diseases. A gluten-free diet is indicated in celiac disease (CD), but some studies show its effectiveness in cases of autoimmunity. The aim of this study was to assess whether the use of a gluten-free diet is also effective in patients with chronic autoimmune thyroid disease (cAITD), which is the most common thyroid autoimmune pathology associated with chronic inflammation, over-reactivity of the immune system, auto-destruction of thyrocytes and hypothyroidism. The final analysis of the study included 62 Caucasian women randomized into a control group (CG: n = 31) and an experimental group on a gluten-free diet (GFDG: n = 31), were subject to a 12-month follow-up, during which the concentrations of thyrotropin (TSH), free triiodothyronine (fT3), free thyroxine (fT4), anti-thyroid peroxidase (anti-TPO) and anti-thyroglobulin (anti-TG) antibodies were assessed at baseline and after 3, 6 and 12 months. During the 12-month follow-up between the CG and the GFDG, no differences were found in anti-TPO and anti-TG antibodies, fT3 or fT4 levels, except a significant reduction in TSH levels in the GFDG. Additionally, performed analysis between individual appointments presented no significant differences in changes in the median concentrations of anti-TPO, anti-TG or fT3, but confirmed a significant decrease in TSH and showed accessory an increase in fT4 after 12 months in GFDG. Statistical analyses performed separately for both groups indicated a constant reduction of anti-TG concentrations in the GFDG. In conclusion, a GFD may be administered in cAITD after ruling out celiac disease, but it is necessary to perform more studies to assess if cAITD patients achieve the benefits of following a GFD. Patients with cAITD should be offered proper nutrition education combined with a healthy lifestyle promotion.

Gluten and FODMAPs Relationship with Mental Disorders: Systematic Review

Nowadays, gluten and FODMAP food components (fermentable oligosaccharides, disaccharides, monosaccharides and polyols) are increasingly studied due to their possible relation with extraintestinal-associated conditions. In recent years, gluten-free diets (GFD) and low-FODMAP diets (LFD) are becoming more popular not only in order to avoid the food components that cause intolerances or allergies in some people, but also due to the direct influence of marketing movements or diet trends on feeding habits. Likewise, neurological and psychiatric diseases are currently of increasing importance in developed countries. For this reason, a bibliographic systematic review has been carried out to analyse whether there is a pathophysiological relationship between the dietary intake of gluten or FODMAPs with mental disorders. This review collects 13 clinical and randomized controlled trials, based on the PRISMA statement, which have been published in the last ten years. Based on these results, limiting or ruling out gluten or FODMAPs in the diet might be beneficial for symptoms such as depression, anxiety (7 out of 7 articles found any positive effect), or cognition deficiency (improvements in several cognition test measurements in one trial), and to a lesser extent for schizophrenia and the autism spectrum. Nevertheless, further studies are needed to obtain completely reliable conclusions.

Perceived impact of information signals on opinions about gluten-free diets

Understanding how people assimilate different types of information for food choices is integral to improving knowledge about diet and human health. This study evaluates the impact that 10 information signals have on the perceived healthiness of gluten. Signals include non-social signals such as personal eating experiences, scientific studies, and advice from doctors, but also includes social signals such as recommendations from attractive people, social media, the layout of a grocery store, and celebrities. An online survey of over 1,000 Americans is administered using indirect questioning where subjects are presented with a hypothetical other person and asked how the various signals would impact that person’s opinion of gluten-free diets. Results show that advice from an attractive person is thought to have a slightly larger impact than reading about a new study regarding gluten, and seeing a grocery store develop a new gluten-free section has a larger impact than learning a celebrity consumes a gluten-free diet.

Long-term symptom severity in people with irritable bowel syndrome following dietetic treatment in primary care: A service evaluation

BACKGROUND

Evidence suggests that dietary interventions can improve symptoms in people with irritable bowel syndrome (IBS), although most data explore the short-term (immediate) impact. Data on long-term (>6 months) impact are limited, especially from primary care settings. The present study aimed to investigate the long-term effect of dietetic-led interventions for IBS delivered in primary care.

METHODS

A service evaluation of a dietetic-led IBS clinic was completed, analysing data on symptom severity, stool frequency and consistency, and healthcare input. Data were collected before and immediately after dietary intervention as part of patients' routine clinical appointments. Long-term data were collected via a postal questionnaire at least 11 months later.

RESULTS

In total, 211 patients responded to the long-term follow-up questionnaire at a median of 13 months (interquartile range 12-16 months) post follow-up appointment. Of these, 84% had been advised to follow a low FODMAP (i.e., fermentable oligosaccharides, disaccharides, monosaccharides and polyols carbohydrates) diet. All symptoms were reported significantly less frequently short term, and all except heartburn and acid regurgitation remained so over the long term. The four most commonly reported bowel symptoms reduced in frequency were abdominal pain (62%), bloating (50%), increased wind (48%) and urgency to open bowels (49%) (p < 0.001). The percentage of patients reporting satisfactory relief of gut symptoms was 10% at baseline and 55% at long-term follow-up (p < 0.001). Visits to a general practitioner were reduced (from 96% to 34%; p < 0.001), as were those to the gastroenterologist (from 37% to 12%; p = 0.002), during the year prior to long-term follow-up compared to the year prior to dietary intervention.

CONCLUSIONS

Patients with IBS who received dietetic-led interventions in primary care reported long-term symptoms improvements that may result in reduced healthcare usage.

FODMAP intake in children with coeliac disease influences diet quality and health-related quality of life and has no impact on gastrointestinal symptoms

Children with coeliac disease (CD) following the gluten-free diet may experience ongoing gastrointestinal symptoms despite strict adherence. The study objective was to evaluate the association between foods high in fermentable oligo/di/monosaccharides, and polyols (FODMAP) and gastrointestinal symptoms, and the potential implications to diet quality and health-related quality of life in CD children. Dietary intake was studied in age-sex matched children 5-18 years (CD, n = 46; non-coeliac mild chronic gastrointestinal complaints [GIC], n = 46; healthy controls [HC], n = 46). CD children consumed fewer foods high in FODMAPs compared to GIC and HC (p < .0001). FODMAP intake was not related to gastrointestinal symptoms in CD children (p > 0.05) but was positively associated with child health-related quality of life (p < 0.05). FODMAP intake from fruits and vegetables was positively associated with diet adequacy and total diet quality in CD children (p < 0.05). FODMAP intake may influence diet quality and health-related quality of life but has no impact on gastrointestinal symptoms in CD children.

Food-specific serum IgG and symptom reduction with a personalized, unrestricted-calorie diet of six weeks in Irritable Bowel Syndrome (IBS)

Background

Irritable Bowel Syndrome (IBS) is a widespread disease with variable symptoms that have an important impact on the quality of life. Despite the prevalence of IBS, its etiology and pathophysiology are still to be fully understood, but immune response is known to be involved. In this study, we investigated the variation of two specific cytokines, B-cell activating factor (BAFF) and platelet-activating factor (PAF), the levels of food-specific IgG and the symptom severity, using Irritable Bowel Syndrome—Symptom Severity Score (IBS-SSS), following a personalized and unrestricted-calorie diet.

Methods

We enrolled 30 subjects with diagnosis of IBS, according to Rome-IV criteria, whose inflammatory markers were measured at baseline and after 6 weeks of dietary intervention. The subjects were monitored in a general practice outpatient setting and nutritional advice was offered remotely via two telephone sessions with a nutritionist.

Results

BAFF and PAF values did not differ between baseline and end of study, both in compliant (C) and non-compliant (NC) subjects. IgG levels significantly decreased only in compliant subjects: 37.32 (23.24–93.67) IU/mL; 27.9 (7.56–93.96) IU/mL (p = 0.02) and in non-compliant went from 51.83 (13.17–113.1) IU/mL to 44.06 (4.96–255.4) IU/mL (p = 0.97, ns). IBS-SSS significantly decreased in both compliant subjects, from 245 (110–480) to 110 (0–140) (p < 0.0001), and non compliant subjects, from 250 (155–370) to 100 (7–220) (p < 0.0001). Comparing IBS-SSS between week 3 and week 6, only compliant subjects had a significant reduction, from 155 (50–355) to 110 (0–140) (p = 0.005), versus non-compliant, from 115 (35–315) to 100 (7–220) (p = 0.33, ns).

Conclusion

These findings support the rapid efficacy and suitability of a personalized dietetic intervention with outside consultation in IBS.

Trial registration: ClinicalTrials.gov ID NCT04348760 Registered April 15, 2020 (retrospectively registered) https://clinicaltrials.gov/show/NCT04348760

The Predictive Value of Serum Cytokines for Distinguishing Celiac Disease from Non-Celiac Gluten Sensitivity and Healthy Subjects

Background

It has been established that the level of some inflammatory cytokines increases in celiac disease (CD) and non-celiac gluten sensitivity (NCGS) in comparison with healthy subjects. Therefore, the primary interest in our research was proposing an accurate tool to diagnose patients with CD and NCGS from healthy individuals in an Iranian population.

Methods

The serum samples were examined in 171 participants, including 110 CD patients, 46 healthy individuals, and 15 NCGS. The commercial ELISA kits were used to detect the level of the following cytokines: IL-1, IL-6, IL-8, IL-15, and IFN-γ. The receiver operating characteristic (ROC) curve analysis was applied to determine the optimal thresholds for high sensitivity, specificity, positive and negative predictive values of cytokines, as the indicators of CD, NCGS, and healthy control groups.

Results

In NCGS group, the values of area under the ROC curve for IL-1, IL-8, and IFN-γ were 71%, 78%, and 70%, respectively. To differentiate the CD and NCGS groups from the control group, IL-15 had the highest sensitivity (82.70%), specificity (56.50%), positive predictive value (81.98%), and negative predictive value (57.78%), followed by IL-8 with the highest sensitivity of 74.50%, specificity of 73.30%, and positive and negative predictive values of 95.35% and 30.21%, respectively.

Conclusion

The obtained results demonstrate that IL-15 and IL-8 could be proposed as potential markers in their optimal cut-off points for distinguishing CD from the NCGS and the healthy control. Based on our findings, the evaluation of cytokine levels can be recommended as a useful tool for the diagnosis of CD and NCGS in a clinical practice.

UEFA expert group statement on nutrition in elite football. Current evidence to inform practical recommendations and guide future research

Football is a global game which is constantly evolving, showing substantial increases in physical and technical demands. Nutrition plays a valuable integrated role in optimising performance of elite players during training and match-play, and maintaining their overall health throughout the season. An evidence-based approach to nutrition emphasising, a 'food first' philosophy (ie, food over supplements), is fundamental to ensure effective player support. This requires relevant scientific evidence to be applied according to the constraints of what is practical and feasible in the football setting. The science underpinning sports nutrition is evolving fast, and practitioners must be alert to new developments. In response to these developments, the Union of European Football Associations (UEFA) has gathered experts in applied sports nutrition research as well as practitioners working with elite football clubs and national associations/federations to issue an expert statement on a range of topics relevant to elite football nutrition: (1) match day nutrition, (2) training day nutrition, (3) body composition, (4) stressful environments and travel, (5) cultural diversity and dietary considerations, (6) dietary supplements, (7) rehabilitation, (8) referees and (9) junior high-level players. The expert group provide a narrative synthesis of the scientific background relating to these topics based on their knowledge and experience of the scientific research literature, as well as practical experience of applying knowledge within an elite sports setting. Our intention is to provide readers with content to help drive their own practical recommendations. In addition, to provide guidance to applied researchers where to focus future efforts.

Functional abdominal pain: what clinicians need to know

Abdominal pain in childhood is extremely common and presents frequently to both primary and secondary care, with many children having recurrent pain which impacts on daily functioning. Despite this most children have no discernible underlying pathology. We discuss the underlying mechanism for functional abdominal pain (visceral hypersensitivity), the evidence base linking parental anxiety and patient symptoms, and how parents can be supported in managing their children's symptoms by addressing questions commonly asked by children and families. We look at the evidence for a one-stop rational approach to investigation including a coeliac screen, inflammatory markers and consideration of stool faecal calprotectin, in the absence of red flags. We evaluate commonly used treatments for functional abdominal pain, within a context of managing family expectations. Given the limitations in pharmacological treatment options, trials of probiotics, peppermint oil, mebeverine and (for short-term use only) hyoscine butylbromide may be appropriate. Psychological interventions including cognitive-behavioural therapy, distraction techniques and hypnotherapy have a better evidence base. There is also some evidence for other complementary therapies in children, including yoga and neurostimulation. Outcome is generally good providing there is child and family acceptance of the multiple factors implicated in the aetiology of the pain.

Gluten consumption may contribute to worldwide obesity prevalence

Gluten consumption has been controversially associated with obesity in previous studies. We sought to examine this association at the worldwide level.

Country specific data were obtained from 168 countries. Scatter plots, bivariate, partial correlation and multiple linear regression models were used to explore and compare the coincidence between obesity prevalence and consumption of gluten, non-gluten cereal protein and total cereal protein respectively. The established risk factors of obesity: caloric intake, sedentary lifestyle, urbanization, socioeconomic status, meat protein intake and sugar consumption were included in analyses as potential confounders. The 168 countries were also stratified into developing and developed country groupings for further examination of the relationships.

Worldwide, bivariate correlation analyses revealed that the strength and direction of correlations between all variables (independent, dependent and potential confounders) were at similar levels. Obesity prevalence was positively correlated to gluten consumption but was negatively correlated to consumption of non-gluten cereal protein, and was in almost nil correlation to total cereal protein consumption. These relationships were similar across all countries (n= 168), developed country grouping (N=44) and developing country grouping (n=124). When caloric intake, Gross Domestic Product at Purchasing Power Parity, sedentary lifestyle and urbanization were kept statistically constant in the partial correlation analysis, obesity was significantly correlated to gluten consumption in all countries, developed country grouping and developing country grouping, and was significantly but inversely and weakly correlated to non-gluten cereal protein in all countries and developing countries, and was in almost nil correlation to total cereal protein in all country groupings. Globally, stepwise multiple regression analysis, when all the independent variables and potential confounding factors were included, selected consumption of sugar as the variable having the greatest influence on obesity with R2 = 0.510, while gluten was placed second increasing R2 to 0.596. Gluten consumption may have been emerging as an inconspicuous, but significant cause of obesity. While Westernization has driven the diet patterns worldwide to incorporate more gluten crops, obesity prevalence projection methods may estimate future obesity rates poorly if gluten consumption is not considered.

A Gluten Free Diet in the Management of Epilepsy in People with Coeliac Disease or Gluten Sensitivity

The aim of this review was to assess the effects of a gluten free diet (GFD) in the management of epilepsy in people with coeliac disease (CD) or gluten sensitivity (GS). A systematic approach was used to undertake a literature review. Five electronic databases (PubMed; Scopus; Google Scholar; Cochrane Epilepsy Group specialised register; Cochrane Register of Controlled Trails (CENTRAL) via the Cochrane Register of Online Trials) were searched using predetermined relevant search terms. In total, 668 articles were identified. Duplicates were removed and predefined inclusion and exclusion criteria were applied, and a PRISMA flow chart was produced. Data was extracted using Covidence software. Twelve studies on Epilepsy and CD involving a total of 70 participants were selected for analysis; narrative synthesis was used owing to the small sample sizes in the selected studies. None of the 12 studies meeting inclusion criteria investigated gluten sensitivity and epilepsy. All the included studies support a link between epilepsy and CD. GFD was effective in 44 out of 70 participants across the studies in terms of a reduction of seizures, reduction of antiepileptic drugs (AEDs) or normalisation of EEG pattern. A total of 44 participants showed a reduction in seizures (across eight studies) and complete cessation of seizures was reported in 22 participants. In general, the earlier the GFD is implemented after the onset of seizures, the better the likelihood of the GFD being successful in supporting control of seizures. Mechanisms linking gluten with epilepsy are not fully understood; possible hypotheses include gluten mediated toxicity, immune-induced cortical damage and malabsorption. Evidence suggests the effectiveness of a GFD in supporting the management of epilepsy in patients with CD, although the quality of evidence is low. There appears to be a growing number of neurologists who are prepared to advocate the use of a GFD. A multidisciplinary approaches and further research are recommended. It could be argued that when balancing potential treatments such as AEDs or surgery, a GFD has a low likelihood of harm.

Diet therapy for irritable bowel syndrome

The review provides present information on the pathogenesis of irritable bowel syndrome (IBS), the relationship of endogenous and exogenous factors with the development of IBS-symptoms, questions of diet therapy are discussed, diets traditionally prescribed in IBS treatment and diets, such as FODMAP and gluten-free diet, which are the most promising and have a positive effect on the symptoms of IBS.

An updated overview of spectrum of gluten-related disorders: clinical and diagnostic aspects

The incidence of gluten-related disorders (GRDs) continues to increase and its global prevalence is estimated at approximately 5% of the population. Celiac disease (CD), dermatitis herpetiformis (DH), gluten ataxia (GA), wheat allergy (WA), and non-celiac gluten sensitivity (NCGS) are the five major GRDs that present with a wide range of clinical manifestations. The diagnosis of GRDs can be challenging because the typical and atypical clinical manifestations of the GRDs overlap. In this review, the current definitions of gluten-related disorders, focusing on their clinical features, diagnostic and therapeutic approaches are presented. We concluded that GRDs are usually diagnosed using a combination of clinical features, serological tests, and histopathological findings. Treatment usually involves dietary modification.

Immunogenic Potential of Beer Types Brewed With Hordeum and Triticum spp. Malt Disclosed by Proteomics

The protein/peptide composition of five beer kinds, including two experimental beer-like products brewed with einkorn (Triticum monococcum), a beer labeled as “gluten-free,” a traditional all-barley malt and a wheat (T. aestivum) containing beer, was characterized with HPLC-ESI MS/MS-based proteomics. To enlarge the characterization of the components, the polypeptides were fractionated according to their molecular size (cut-off 6 kDa). All the beer types contained a variety of polypeptides arising from all the gliadin subfamilies (α-/β-, γ-, and ω-gliadins) able to induce an immune response in celiac disease (CD) patients in addition to a panel of IgE-reactive food allergens. Wheat storage proteins were heavily hydrolyzed in the beer samples brewed with einkorn. The presence of gluten-like fragments, also including the 25-mer and 33-mer-like of α-gliadin, was confirmed in beer brewed with barley and wheat malt as well as in the gluten-free beer. Both CD-toxic and allergenic peptides of all beer samples were drastically degraded when subjected to a simulated gastroduodenal (GD) digestion. After in vitro digestion, the level of gluten-like peptides assayed with the G12 competitive ELISA, was below the threshold (20 ppm) for a food to be considered as “gluten-free.” A few gliadin-derived epitopes occurred in the digests of beers crafted with wheat or Norberto-ID331 line of einkorn. In contrast, digests of all barley malt and gluten-free beers did not contain detectable gluten-like epitopes, but only minor fragments of hordeins and IgE-reactive food allergens. All beer samples evoked a weak immune response on gliadin-reactive celiac T cells isolated from intestinal biopsies of celiac patients. Compared to undigested polypeptides, the response was markedly reduced by GD digestion. Although the consumption of a moderate amount of beer brewed with barley or einkorn could deliver a relatively low amount of CD-toxic epitopes, the findings of this study emphasize the urgent need of a reliable and accurate quantification of gluten epitopes in all types of beer, also including the gluten-free one, to compute realistically the contribution of beer to the overall gluten intake, which can be responsible of intestinal tissue damages in celiacs.

Identification and Quantitation of Amylase Trypsin Inhibitors Across Cultivars Representing the Diversity of Bread Wheat

α-Amylase/trypsin inhibitors (ATIs) may have a role in nonceliac wheat sensitivity (NCWS) and celiac disease (CD), but the ATI content and diversity across a range of wheat cultivars are not well characterized. Discovery proteomics was used to detect ATIs across two wheat cultivars: Chara and Magenta. Comprehensive mapping of detected ATIs with the ATIs from the recently published wheat genome RefSeq v1.0 shows the presence of three major subclasses: monomeric (9%), dimeric (61%), and chloroform-methanol (CM) type (30%). Subsequently, the level of 18 ATI isoforms (63 peptides) grouped into four subtypes was monitored across 15 commercial wheat cultivars and the eight parental lines from a multiparent advanced-generation intercross (MAGIC) population using liquid chromatography-multiple reaction monitoring-mass spectrometry (LC-MRM-MS). The ATI content of wheat cultivars Janz, Sunvale, Diamond Bird, and Longreach Scout was significantly lower than that of other wheat cultivars. The MAGIC parental cultivars Baxter and Xiaoyan 54 contain higher levels (∼115% relative to the average wheat ATI content), whereas cultivar Pastor contained the lowest levels (∼87%). Comprehensive sequence analysis, annotation, chromosomal locations, and epitope mapping enabled us to build an LC-MRM-MS method to monitor and quantify the immunostimulatory ATI proteins potentially related to NCWS, autoimmune diseases, and metabolic disorders. This provides an opportunity to select wheat cultivars with significantly lower levels of ATIs.

Pathogenesis of Celiac Disease and Other Gluten Related Disorders in Wheat and Strategies for Mitigating Them

Wheat is a major cereal crop providing energy and nutrients to the billions of people around the world. Gluten is a structural protein in wheat, that is necessary for its dough making properties, but it is responsible for imparting certain intolerances among some individuals, which are part of this review. Most important among these intolerances is celiac disease, that is gluten triggered T-cell mediated autoimmune enteropathy and results in villous atrophy, inflammation and damage to intestinal lining in genetically liable individuals containing human leukocyte antigen DQ2/DQ8 molecules on antigen presenting cells. Celiac disease occurs due to presence of celiac disease eliciting epitopes in gluten, particularly highly immunogenic alpha-gliadins. Another gluten related disorder is non-celiac gluten-sensitivity in which innate immune-response occurs in patients along with gastrointestinal and non-gastrointestinal symptoms, that disappear upon removal of gluten from the diet. In wheat allergy, either IgE or non-IgE mediated immune response occurs in individuals after inhalation or ingestion of wheat. Following a life-long gluten-free diet by celiac disease and non-celiac gluten-sensitivity patients is very challenging as none of wheat cultivar or related species stands safe for consumption. Hence, different molecular biology, genetic engineering, breeding, microbial, enzymatic, and chemical strategies have been worked upon to reduce the celiac disease epitopes and the gluten content in wheat. Currently, only 8.4% of total population is affected by wheat-related issues, while rest of population remains safe and should not remove wheat from the diet, based on false media coverage.

Incidence and prevalence of self-reported non-coeliac wheat sensitivity and gluten avoidance in Australia

OBJECTIVES

To determine the incidence of self-reported non-coeliac wheat sensitivity (SR-NCWS) and factors associated with its onset and resolution; to describe the prevalence of factors associated with gluten avoidance.

DESIGN

Longitudinal cohort study; analysis of responses to self-administered validated questionnaires (Digestive Health and Wellbeing surveys, 2015 and 2018).

SETTING, PARTICIPANTS

Subset of an adult population sample randomly selected in 2015 from the electoral rolls for the Newcastle and Gosford regions of New South Wales.

MAIN OUTCOME MEASURES

Prevalence of SR-NCWS (2015, 2018) and incidence and resolution of SR-NCWS, each by demographic and medical factors; prevalence of gluten avoidance and reasons for gluten avoidance (2018).

RESULTS

1322 of 2185 eligible participants completed the 2018 survey (response rate, 60.5%). The prevalence of SR-NCWS was similar in 2015 (13.8%; 95% CI, 12.0-15.8%) and 2018 (13.9%; 95% CI, 12.1-15.9%); 69 of 1301 respondents (5.3%) reported developing new onset (incident) SR-NCWS between 2015 and 2018 (incidence, 1.8% per year). Incident SR-NCWS was significantly associated with a diagnosis of functional dyspepsia, and negatively associated with being male or older. Gluten avoidance was reported in 2018 by 24.2% of respondents (20.5% partial, 3.8% complete avoidance); general health was the most frequent reason for avoidance (168 of 316 avoiders, 53%). All 13 participants with coeliac disease, 56 of 138 with irritable bowel syndrome (41%), and 69 of 237 with functional dyspepsia (29%) avoided dietary gluten.

CONCLUSIONS

The prevalence of SR-NCWS was similar in 2015 and 2018. Baseline (2015) and incident SR-NCWS (2018) were each associated with functional gastrointestinal disorders. The number of people avoiding dietary gluten exceeds that of people with coeliac disease or SR-NCWS, and general health considerations and abdominal symptoms are the most frequently reported reasons for avoidance.

Implementation of the low FODMAP diet in functional gastrointestinal symptoms: A real-world experience

BACKGROUND

The low FODMAP (fermentable oligo-, di-, monosaccharides, and polyols) diet reduces functional gastrointestinal symptoms (FGID) when implemented by dietitian-delivered education in clinical trials, but it is unknown how well the diet is followed in routine clinical care and if differences exist when implemented by physician or dietitian. This study aimed to evaluate the real-world experience of patients recommended the diet.

METHODS

This case-series interviewed FGID patients attending a gastroenterology clinic with previous recommendation to trial the low FODMAP diet, examining who recommended the diet and what their percentage improvement was. To evaluate implementation of the diet's 3 phases, questions were constructed based on current literature and clinical guidelines regarding length of initial restriction and food knowledge (Phase-1), number of foods re-challenged (Phase-2) and food re-introduction as tolerated (Phase-3). The comprehensive nutrition assessment questionnaire provided daily FODMAP intake. Data were analyzed using chi-squared tests.

KEY RESULTS

In 80 patients (21 male), the diet was recommended by the gastroenterologist in 53%, general practitioner 22%, dietitian 9% and other 15%. 30% saw a dietitian for guidance. 55% reported a ≥50% symptom improvement. The diet was followed appropriately during Phase-1 by 78% (with vs without a dietitian, 96% vs 71%; P = .02), Phase-2 by 48% (70% vs 39%; P = .02) and Phase-3 by 40% (65% vs 29%; P < .01). A FODMAP intake of <12 g/d (considered therapeutic) was achieved by 44% (72% vs 31%; P < .01).

CONCLUSIONS & INFERENCES

Symptom improvement was reported in half of patients, but many did not reach the therapeutic FODMAP intake target, especially without dietitian education. Compliance was poor in Phase-2 and Phase-3 but improved with dietitian guidance.

All that a physician should know about FODMAPs

A diet low in poorly absorbed, fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPs) is now considered as an effective strategy for symptoms control in patients with irritable bowel syndrome (IBS). The low FODMAP diet is administered in three phases, namely restriction of all dietary FODMAPs followed by rechallenge and then reintroduction of specific FODMAPs according to the tolerance of patients. A dietician should be involved in patients in whom a low FODMAP diet is planned. While restricting high FODMAPs, it is pertinent that patients are advised a well-balanced diet and suitable alternatives with low FODMAP contents in each food groups are prescribed. Strict adherence to a low FODMAP diet has been shown to improve symptoms, stool output, quality of life, and the overall well-being of patients with IBS. For those who do not respond to this dietary approach, a normal diet may be initiated and other treatment strategies (dietary or nondietary) should be considered. Interestingly, the low FODMAP diet has also been tried in other functional disorders, nonceliac gluten sensitivity, and even inflammatory bowel disease. Since the concept of FODMAP is relatively new, there is only limited data on the content of FODMAP in the Indian food items and there is a need to address this question. There is also a need for well-designed and adequately powered studies to explore the efficacy of low FODMAP diet in patients with IBS. In the present review article, we have compiled all the relevant information about FODMAPs with an objective to provide comprehensive information on FODMAPs to a physician.

Dietary Practices Adopted by Track-and-Field Athletes: Gluten-Free, Low FODMAP, Vegetarian, and Fasting

Some track-and-field athletes implement special diets aiming to improve health and/or performance. An evidence-based approach to any diet is recommended to minimize the risks associated with unnecessary dietary restriction, which may potentially do more harm than good. Four prevalent diets are reviewed in this study: (a) gluten-free; (b) low fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAP); (c) vegetarian; and (d) fasting diets. Recently, gluten-free diets and low FODMAP diets have emerged as novel regimes thought to improve gastrointestinal health and reduce the risk of exercise-associated gastrointestinal symptoms. No direct beneficial outcomes have been associated with avoiding gluten for clinically healthy athletes. Indirectly, a gluten-free diet is associated with other dietary changes, particularly FODMAP reduction, which may improve adverse gastrointestinal symptoms. Vegetarian diets can optimally support athletic demands. However, attention is required to ensure adequate energy and intake of specific nutrients that are less abundant or less well absorbed from plant sources. Finally, fasting is a long-standing concept that is undertaken on a voluntary and obligatory basis. Despite limited supporting research, voluntary fasting is a popular alternative to conventional diets perceptually offering health and body composition benefits. Strict obligatory fasting guidelines likely require the implementation of tailored nutrition strategies to help athletes cope with athletic demands. Overall, a multitude of factors influence adherence to special diets. Even when adherence to a special diet is a necessity, education and advice from an accredited dietitian/nutritionist are recommended for track-and-field athletes to optimize nutrition for health and performance.

IRRITABLE BOWEL SYNDROME, FOOD INTOLERANCE AND NON- CELIAC GLUTEN SENSITIVITY. A NEW CLINICAL CHALLENGE

Approximately 80% of irritable bowel syndrome (IBS) patients report that their symptoms are triggered after ingesting one or specific food groups. Gluten, wheat and related proteins (e.g., amylase-trypsin inhibitors, and fermentable oligo-di-mono-saccharides and polyols (FODMAPs) are the most relevant IBS symptom triggers, although the true 'culprit(s)' is/are still not well established. The concept of causal relationship between gluten intake and the occurrence of symptoms in the absence of celiac disease and wheat allergy was termed non-celiac gluten sensitivity (NCGS). The borderline between celiac disease, wheat allergy, IBS and NCGS is not always clearly distinguishable, and the frequency and clinical identity of NGCS are still unclear. An overlap between IBS and NCGS has been detected. The incomplete knowledge of the etiopathogenesis of these clinical conditions, lack of data on their real epidemiology, as well as the absence of a gold standard for their diagnosis, make the overall picture difficult to understand "It is crucial to well define the interaction between IBS, food intolerance and NGCS, since the role of diet in IBS and its dietary management is an essential tool in the treatment of a large number of these patients". The objective of the present review is to provide an overview highlighting the interaction between IBS, food intolerance and NCGS in order to unravel whether gluten/wheat/FODMAP sensitivity represents 'facts' and not 'fiction' in IBS symptoms.

Dietary therapies for functional bowel symptoms: Recent advances, challenges, and future directions

BACKGROUND

Functional gastrointestinal symptoms in irritable bowel syndrome (IBS) and quiescent inflammatory bowel disease (IBD) cause significant morbidity and a reduction in quality of life. Multiple dietary therapies are now available to treat these symptoms, but supporting evidence for many is limited. In addition to a further need for studies demonstrating efficacy and mechanism of action of dietary therapies, the risk of nutritional inadequacy, alterations to the microbiome and changes in quality of life are key concerns requiring elucidation. Identifying predictors of response to dietary therapy is an important goal as management could be tailored to the individual to target specific dietary components, and thereby reduce the level of dietary restriction necessary.

PURPOSE

This review discusses the available dietary therapies to treat symptoms in patients with IBS and patients with quiescent IBD suffering from IBS symptoms, with the aim to understand where current dietary evidence lies and how to move forward in dietary research in this field.

Celiac Disease and Gluten Sensitivity

Celiac disease is an immune-mediated enteropathy triggered by gluten that affects genetically predisposed individuals, typically causing intestinal symptoms and malabsorption. Diagnosis requires stepwise evaluation with anti-tissue transglutaminase IgA and histologic analysis of the small bowel. Strict adherence to a gluten-free diet is the primary treatment. Patients with symptoms thought to be related to gluten but without evidence of celiac disease are difficult to diagnose and treat. Consider first advising general nutritional improvements. If symptoms persist, involve a trained dietitian for restrictive diets and consider evaluation for small intestinal bacterial overgrowth or other treatments for irritable bowel syndrome.

Potential impact of genome editing in world agriculture

Changeable biotic and abiotic stress factors that affect crop growth and productivity, alongside a drive to reduce the unintended consequences of plant protection products, will demand highly adaptive farm management practices as well as access to continually improved seed varieties. The former is limited mainly by cost and, in theory, could be implemented in relatively short time frames. The latter is fundamentally a longer-term activity where genome editing can play a major role. The first targets for genome editing will inevitably be loss-of-function alleles, because these are straightforward to generate. In addition, they are likely to focus on traits under simple genetic control and where the results of modification are already well understood from null alleles in existing gene pools or other knockout or silencing approaches such as induced mutations or RNA interference. In the longer term, genome editing will underpin more fundamental changes in agricultural performance and food quality, and ultimately will merge with the tools and philosophies of synthetic biology to underpin and enable new cellular systems, processes and organisms completely. The genetic changes required for simple allele edits or knockout phenotypes are synonymous with those found naturally in conventional breeding material and should be regulated as such. The more radical possibilities in the longer term will need societal engagement along with appropriate safety and ethical oversight.

Low fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAP) diet improves symptoms in adults suffering from irritable bowel syndrome (IBS) compared to standard IBS diet: A meta-analysis of clinical studies

BACKGROUND

Irritable bowel syndrome (IBS) and functional digestive tract disorders, e.g. functional bloating, carbohydrate maldigestion and intolerances, are very common disorders frequently causing significant symptoms that challenge health care systems. A low Fermentable Oligosaccharides, Disaccharides, Monosaccharides and Polyols (FODMAP) diet is one of the possible therapeutic approaches for decreasing abdominal symptoms and improving quality of life.

OBJECTIVES

We aimed to meta-analyze data on the therapeutic effect of a low-FODMAP diet on symptoms of IBS and quality of life and compare its effectiveness to a regular, standard IBS diet with high FODMAP content, using a common scoring system, the IBS Symptom Severity Score (IBS-SSS).

METHODS

A systematic literature search was conducted in PubMed, EMBASE and the Cochrane Library as well as in the references in a recent meta-analysis. Adult patients diagnosed with IBS according to the Rome II, Rome III, Rome IV or NICE criteria were included in the analysis.

STATISTICAL METHODS

Mean differences with 95% confidence intervals were calculated from studies that contained means, standard deviation (SD) or mean differences and SD of differences and p-values. A random effect model was used because of the heterogeneity (Q test (χ2) and I2 indicator). A p-value of less than 0.05 was chosen to indicate a significant difference.

RESULTS

The literature search yielded 902 publications, but only 10 were eligible for our meta-analysis. Both regular and low-FODMAP diets proved to be effective in IBS, but post-diet IBS-SSS values were significantly lower (p = 0.002) in the low-FODMAP group. The low-FODMAP diet showed a correlation with the improvement of general symptoms (by IBS-SSS) in patients with IBS.

CONCLUSIONS

This meta-analysis provides high-grade evidence of an improved general symptom score among patients with irritable bowel syndrome who have maintained a low-FODMAP diet compared to those on a traditional IBS diet, therefore showing its superiority to regular IBS dietary therapy. These data suggest that a low-FODMAP diet with dietitian control can be a candidate for first-line therapeutic modality in IBS. Because of a lack of data, well-planned randomized controlled studies are needed to ascertain the correlation between improvement of separate key IBS symptoms and the effect of a low-FODMAP diet.

Diet in irritable bowel syndrome: What to recommend, not what to forbid to patients!

A substantial proportion of patients with irritable bowel syndrome (IBS) associate their symptoms with the ingestion of specific foods. Therefore, in recent years, scientific research has increasingly focused on the role of diet in IBS and dietary management is now considered an important tool in IBS treatment. This article reviews the main dietary approaches in IBS emphasizing evidence from experimental and observational studies and summarizing the main diet and lifestyle recommendations provided by dietary guidelines and scientific literature. Despite the limited evidence for a beneficial role, general advice on healthy eating and lifestyle is recommended as the first-line approach in the dietary management of IBS. Standard recommendations include adhering to a regular meal pattern, reducing intake of insoluble fibers, alcohol, caffeine, spicy foods, and fat, as well as performing regular physical activity and ensuring a good hydration. Second-line dietary approach should be considered where IBS symptoms persist and recommendations include following a low FODMAP diet, to be delivered only by a healthcare professional with expertise in dietary management. The efficacy of this diet is supported by a growing body of evidence. In contrast, the role of lactose or gluten dietary restriction in the treatment of IBS remains subject to ongoing research with a lack of high-quality evidence. Likewise, further clinical trials are needed to conclude the efficacy of probiotics on IBS symptoms.

Low FODMAP in 2017: Lessons learned from clinical trials and mechanistic studies

Given the prevalence of irritable bowel syndrome (IBS) and the suboptimal response to most therapeutic approaches, there has been increasing interest in and adoption of dietary treatment strategies, such as the low Fermentable Oligo-, Di-, & Mono-Saccharides and Polyols (FODMAP) diet. FODMAPs are a diverse group of carbohydrates that exert effects in the gastrointestinal tract not only via fermentation but likely via alterations in the microbiota, metabolome, permeability, and intestinal immunity as well. Clinical evidence for efficacy of this diet is mounting, but there are significant questions regarding short- and long-term safety and effects on the microbiota and nutrition that remain unanswered. This review article interprets the recent findings reported in this issue of Neurogastroenterology and Motility and summarizes the mechanistic and clinical efficacy data of the low FODMAP diet in IBS patients to date.