A Population Survey of Dietary Attitudes towards Gluten

The effect of expectancy versus actual gluten intake on gastrointestinal and extra-intestinal symptoms in non-coeliac gluten sensitivity: a randomised, double-blind, placebo-controlled, international, multicentre study

BACKGROUND

Many individuals without coeliac disease or wheat allergy reduce their gluten intake because they believe that gluten causes their gastrointestinal symptoms. Symptoms could be affected by negative expectancy. Therefore, we aimed to investigate the effects of expectancy versus actual gluten intake on symptoms in people with non-coeliac gluten sensitivity (NCGS).

METHODS

This randomised, double-blind, placebo-controlled, international, multicentre study was done at the University of Leeds (Leeds, UK), Maastricht University (Maastricht, the Netherlands), and Wageningen University and Research (Wageningen, the Netherlands). People aged 18-70 years with self-reported NCGS (ie, gastrointestinal symptoms within 8 h of gluten consumption) without coeliac disease and wheat allergy were recruited. Participants had to follow a gluten-free or gluten-restricted diet for at least 1 week before (and throughout) study participation and had to be asymptomatic or mildly symptomatic (overall gastrointestinal symptom score ≤30 mm on the Visual Analogue Scale [VAS]) while on the diet. Participants were randomly assigned (1:1:1:1; blocks of eight; stratified by site and gender) to one of four groups based on the expectation to consume gluten-containing (E+) or gluten-free (E-) oat bread for breakfast and lunch (two slices each) and actual intake of gluten-containing (G+) or gluten-free (G-) oat bread. Participants, investigators, and those assessing outcomes were masked to the actual gluten assignment, and participants were also masked to the expectancy part of the study. The primary outcome was overall gastrointestinal symptom score on the VAS, which was measured at and corrected for baseline (before breakfast) and hourly for 8 h, with lunch served after 4 h, and analysed per-protocol. Safety analysis included all participants incorporated in the per-protocol analysis. The study is registered at ClinicalTrials.gov, NCT05779358, and has ended.

FINDINGS

Between Oct 19, 2018, and Feb 14, 2022, 165 people were screened and 84 were randomly assigned to E+G+ (n=21), E+G- (n=21), E-G+ (n=20), or E-G- (n=22). One person in the E+G+ group was excluded due to not following test day instructions, leaving 83 participants in the per-protocol analysis. Median age was 27·0 years (IQR 21·0-45·0), 71 (86%) of 83 people were women, and 12 (14%) were men. Mean overall gastrointestinal symptom score was significantly higher for E+G+ (16·6 mm [95% CI 13·1 to 20·0]) than for E-G+ (6·9 mm [3·5 to 10·4]; difference 9·6 mm [95% CI 3·0 to 16·2], p=0·0010) and E-G- (7·4 mm [4·2 to 10·7]; difference 9·1 mm [2·7 to 15·6], p=0·0016), but not for E+G- (11·7 mm [8·3 to 15·1]; difference 4·9 mm [-1·7 to 11·5], p=0·28). There was no difference between E+G- and E-G+ (difference 4·7 mm [-1·8 to 11·3], p=0·33), E+G- and E-G- (difference 4·2 mm [-2·2 to 10·7], p=0·47), and E-G+ and E-G- (difference -0·5 mm [-7·0 to 5·9], p=1·0). Adverse events were reported by two participants in the E+G- group (itching jaw [n=1]; feeling lightheaded and stomach rumbling [n=1]) and one participant in the E-G+ group (vomiting).

INTERPRETATION

The combination of expectancy and actual gluten intake had the largest effect on gastrointestinal symptoms, reflecting a nocebo effect, although an additional effect of gluten cannot be ruled out. Our results necessitate further research into the possible involvement of the gut-brain interaction in NCGS.

FUNDING

Government of the Netherlands Topsector Agri & Food Top Consortium for Knowledge and Innovation, AB Mauri Global Bakery Ingredients, Baking Industry Research Trust, Borgesius-Albert Heijn, CSM Innovation Centre, the International Maize and Wheat Improvement Center (CIMMYT), DSM Food Specialties, Fazer, Healthgrain Forum, the International Association for Cereal Science and Technology, the International Wheat Gluten Association, Lantmännen, Mondelez International, Nederlands Bakkerij Centrum, Nutrition & Santé, Puratos, Rademaker, Sonneveld Group, and Zeelandia HJ Doeleman.

Association between Food-Specific Immunoglobulin G4 Antibodies in Adults with Self-Reported Signs and Symptoms Attributed to Adverse Reactions to Foodstuffs

Signs and symptoms attributed to adverse reactions to foodstuffs (ARFS) need tools for research and evaluation in clinical practice. The objectives of this study were (a) to evaluate the most frequent self-reported signs and symptoms attributed to ARFS in Spanish adults, (b) to determine the prevalence of food-specific IgG4 antibody reactions (AbRs), and (c) to investigate the association between self-reported ARFS symptomatology and food-specific IgG4 AbRs. Food-specific IgG4 AbRs against 57 common food and beverages (AESKUCARE-T2FA® in vitro point-of-care test kit, Aesku.Diagnostics GmbH, Germany) were determined in capillary blood samples of 205 volunteers living in the Region of Madrid (Spain). The most frequent self-reported signs and symptoms were related to skin (43%), digestive (41%), and nervous system (NS, 33%) problems. The prevalence of food-specific IgG4 AbRs was cow's milk (73%), sheep's milk (70%), casein (66%), and goat's milk (56.10%). Positive IgG4 AbRs against tomato had a profile consisting of 3/4 of skin problems, more than half of digestive, and 2/5 of NS self-reported signs and symptoms. In conclusion, at least 1/3 of the studied sample reported skin, digestive, and NS signs and symptoms. The most frequent food-specific IgG4 AbRs were related to dairy. Skin problems were more frequent in positive tomato IgG4 AbRs.

Methods to assess ambivalence towards food and diet: a scoping review

BACKGROUND

Ambivalence towards food and diet, which favours behavioural inertia, might be a barrier to adopting healthier eating behaviours. Measuring it can help researchers to better understand its relationship with behaviour change and design interventions aimed at resolving it. In this scoping review, we map and describe methods and tools employed in studies to assess, measure or classify the ambivalence of participants towards food- and diet-related attitude objects.

METHODS

In accordance with Joanna Briggs Institute guidance for conducting scoping reviews, we retrieved peer-reviewed studies from MEDLINE, CINAHL, PsycINFO, Web of Science, FSTA and Food Science Source and preprints from PsyArXiv and MedRxiv. Two independent reviewers screened the articles. We considered for inclusion peer-reviewed studies and preprints that assessed the ambivalence of participants of any age, sex or sociodemographic group towards food and diet.

RESULTS

We included 45 studies published between 1992 and 2022, which included participants from 17 countries. Eighteen methods were employed across the included studies to assess different types of ambivalence (felt, potential or cognitive-affective), the most frequent of which were the Griffin Index, the Subjective Ambivalence Questionnaire, the MouseTracker Paradigm and the Orientation to Chocolate Questionnaire.

CONCLUSION

This scoping review identified several methods and tools to assess different types of ambivalence towards food- and diet-related objects, providing an array of options for future studies.

Design and validity of the Spanish version of two questionnaires related to adverse reactions to foodstuffs

Introduction

Introduction: there is an emerging current necessity of valid questionnaires, encompassing most of food, beverages, diseases, signs and symptoms currently related to the pathogenesis of adverse reactions to foodstuffs (ARFS) in the Spanish population. Objectives: this study aimed to design and validate two questionnaires to assess ARFS in the Spanish population, Food and Beverages Frequency Consumption Questionnaire to Identify Adverse Reactions to Foodstuffs (FBFC-ARFSQ-18); and Pathologies and Symptomatology Questionnaire associated with Adverse Reactions to Foodstuffs (PSIMP-ARFSQ-10). Methods: both questionnaires were designed adapting questionnaires from the literature; and validated, using the expert judgment method, in five phases: questionnaires development, pilot test and reliability, content validity, face validity, and ethical considerations. Questionnaires were developed using the REDCap™ tool hosted at the Universidad Politécnica de Madrid. A total of 20 Spanish experts evaluated the questionnaires. Cronbach's alpha reliability coefficients were calculated using SPSS version 25.0 (IBM Corp., Armonk, NY-USA) and Aiken's V coefficient values were calculated using ICaiken.exe (Visual Basic 6.0, Lima-Perú). Results: a final construct of questions was designed, ensuring no overlap, for FBFC-ARFSQ-18 and PSIMP-ARFSQ-10. Cronbach's alpha reliability coefficients were 0.93 and 0.94; and Aiken's V coefficient values were 0.90 (0.78-0.96 CI) and 0.93 (0.81-0.98 CI) for FBFC-ARFSQ-18 and PSIMP-ARFSQ-10, respectively. Conclusions: both validated questionnaires could be used to analyze the association between certain food and beverages consumption with ARFS, such as food allergies and food intolerances; also, to investigate the link between some specific diseases, signs and symptoms with ARFS.

The Effect of a Gluten-Free Diet on Vitamin D Metabolism in Celiac Disease: The State of the Art

Celiac disease is a chronic autoimmune disorder involving the small intestine, characterized by villous atrophy, crypt hyperplasia and an increase in intraepithelial lymphocytes. Due to both calcium malabsorption and immune activation, a high prevalence of bone mass derangement is evident in this condition, regardless of the presence of overt malabsorption. Alterations of mineral metabolism are also frequently described, and in this review, the modifications of serum levels of vitamin D are analyzed, according to the available literature on this topic. In untreated patients, secondary hyperparathyroidism is responsible for the hyperconversion of 25-vitamin D into 1,25-vitamin D making mandatory the determination of serum levels of both vitamin metabolites to avoid a wrong diagnosis of vitamin D deficit. A gluten-free diet allows for a normalization of bone and mineral metabolism, reverting these abnormalities and raising some doubts on the need for vitamin supplementation in all the patients. Data available do not support this wide indication, and a complete evaluation of bone and mineral metabolism should be performed to select patients who need this therapeutic approach.

Usefulness of Vaccine Adverse Event Reporting System for Machine-Learning Based Vaccine Research: A Case Study for COVID-19 Vaccines

Usefulness of Vaccine-Adverse Event-Reporting System (VAERS) data and protocols required for statistical analyses were pinpointed with a set of recommendations for the application of machine learning modeling or exploratory analyses on VAERS data with a case study of COVID-19 vaccines (Pfizer-BioNTech, Moderna, Janssen). A total of 262,454 duplicate reports (29%) from 905,976 reports were identified, which were merged into a total of 643,522 distinct reports. A customized online survey was also conducted providing 211 reports. A total of 20 highest reported adverse events were first identified. Differences in results after applying various machine learning algorithms (association rule mining, self-organizing maps, hierarchical clustering, bipartite graphs) on VAERS data were noticed. Moderna reports showed injection-site-related AEs of higher frequencies by 15.2%, consistent with the online survey (12% higher reporting rate for pain in the muscle for Moderna compared to Pfizer-BioNTech). AEs {headache, pyrexia, fatigue, chills, pain, dizziness} constituted >50% of the total reports. Chest pain in male children reports was 295% higher than in female children reports. Penicillin and sulfa were of the highest frequencies (22%, and 19%, respectively). Analysis of uncleaned VAERS data demonstrated major differences from the above (7% variations). Spelling/grammatical mistakes in allergies were discovered (e.g., ~14% reports with incorrect spellings for penicillin).

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.

Calcium and Iron Content of Cereal-Based Gluten-Free Products

The impact of a gluten-free (GF) diet on the intake of calcium and iron is broadly unknown, as the micronutrient content of GF cereal-based products has scarcely been measured. The study aimed to measure the calcium and iron content of GF cereal-based products from the UK. Seventy-three GF products were analysed. A laboratory analysis of calcium and iron from GF food samples was performed by spectrophotometric and flame emission photometry, respectively. The values for wheat-based products were from a nutrient database. The calcium in GF white loaf samples varied greatly from 54 to 140 mg/100 g, with a lower average calcium content compared with wheat-based values (99 ± 29 mg/100 g n = 13 versus 177 mg/100 g; p < 0.01). Only 27% of the white loaves and rolls were fortified with calcium; this contrasts with 100% of white wheat-based loaves. The calcium in GF flour mixes ranged from 54 to 414 mg/100 g, with 66% fortified. GF white pasta had more calcium compared with wheat-based pasta (76 ± 27 mg/100 g n = 7 versus 24 mg/100 g; p = 0.002). The iron in GF bread loaves and pasta samples was similar to wheat-based comparators, whereas lower iron levels were observed in GF wraps (0.8 ± 0.2 n = 11 versus 1.6 mg/100 g). GF bread had a significantly higher fibre content, and the majority of GF bread had a lower protein content, compared with wheat-based bread products. These calcium and iron values provide a valuable addition towards enabling more accurate nutrient intake analysis for adults and children with coeliac disease.

Plant-Based Proteins: The Good, Bad, and Ugly

Our global population is growing at a pace to exceed 10 billion people by the year 2050. This growth will place pressure on the agricultural production of food to feed the hungry masses. One category that will be strained is protein. Per capita protein consumption is rising in virtually every country for both nutritional reasons and consumption enjoyment. The United Nations estimates protein demand will double by 2050, and this will result in a critical overall protein shortage if drastic changes are not made in the years preceding these changes. Therefore, the world is in the midst of identifying technological breakthroughs to make protein more readily available and sustainable for future generations. One protein sourcing category that has grown in the past decade is plant-based proteins, which seem to fit criteria established by discerning consumers, including healthy, sustainable, ethical, and relatively inexpensive. Although demand for plant-based protein continues to increase, these proteins are challenging to utilize in novel food formulations.

Expected final online publication date for the Annual Review of Food Science and Technology, Volume 13 is March 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Nutritional implications of dietary gluten avoidance among Canadians: results from the 2015 Canadian Community Health Survey

Adherence to a gluten-free diet (GFD) is the only available treatment for gluten-related disorders, although a GFD may also be followed for discretionary reasons. The main objectives of the present study were to (1) describe and test for differences in key nutrient intakes among Canadians who follow a GFD compared with Canadians with no dietary exclusions and (2) describe additional dietary avoidances adhered to by Canadians who avoid gluten. We conducted a secondary analysis of the cross-sectional 2015 Canadian Community Health Survey-Nutrition Survey, which included a general health survey and 24-h dietary recall (n 20 487). Participants were categorised as those who avoid dietary gluten and those who reported no avoidances. Key nutrient intakes were assessed, as a percentage of Dietary Recommended Intakes, including fibre, B vitamins, vitamin D, Ca, Fe, Na and Zn, and compared between the two groups using t tests. Canadians who avoided gluten had significantly lower intakes of folate, vitamin B12, vitamin D, Fe, Na and Ca compared with those who did not avoid any food groups. However, Canadians who reported following a GFD were significantly more likely to use vitamin or mineral supplements in the past 30 d. More than 20 % of those who avoided gluten also avoided dairy products. Findings suggest that following a GFD places Canadians at risk for nutrient inadequacies, particularly folate, Ca and vitamin D. Further research is required to further examine how multiple dietary avoidances among those who avoid gluten may contribute to dietary inadequacies.

Knowledge of Medical Students and Medical Professionals Regarding Nutritional Deficiencies in Patients with Celiac Disease

A gluten-free diet provides relief from symptoms for patients with celiac disease, although there is still a risk of nutritional deficiencies. These patients can potentially consume an excessive amount of fat and insufficient amounts of fiber, iron, vitamin D, and calcium. This study aimed to assess the knowledge of medical students and healthcare professionals in Poland regarding nutritional deficiencies and the prevention of such deficiencies in patients with celiac disease who are on a gluten-free diet. Of the 430 survey participants, 46% did not realize the risk of nutritional deficiencies in patients with celiac disease. The knowledge of the participants was lowest regarding the risk of being overweight or obese. Among the healthcare professionals, an acceptable level of correct answers was provided by only 37% of individuals and was highest for the dietitians’ group. Our results demonstrate the need to improve the education of healthcare professionals concerning nutrition in patients with celiac disease.

Assessment of price and nutritional quality of gluten-free products versus their analogues with gluten through the algorithm of the nutri-score front-of-package labeling system

Evidence has shown that the nutritional quality of gluten-free products (GFPs) is lower than that of non-GFPs. Our main objective was to compare the nutritional quality through nutritional profiles of foods underlying the Nutri-Score front-of-pack and the price of GFPs with respect to non-GFPs, and to evaluate whether there is a correlation between both parameters. Nutritional information of all products was obtained from the CELIACBASE database and the price through Spanish supermarkets websites. Global quality using the Nutri-Score algorithm and the price were compared between both types of products. GFPs do not always have poorer quality than their counterparts. A better quality of gluten-free pasta was correlated with the higher price but also a worse quality of gluten-free muesli was correlated with the higher price. The price of GFPs compared to non-GFPs was higher up to 391.5%. However, for ham and cheese pizza, ham pizza, Marie biscuits, and baby biscuits, the difference was not statistically significant. Generally, the price of GFPs did not correlate with better nutritional quality. Nutri-Score would ease the nutritional quality identification, empowering consumers and could also influence manufacturers to improve the nutritional quality of GFPs. Nowadays, given that many GFPs have poor nutritional quality, they should be included only occasionally in a balanced gluten-free diet.

Long-term Intake of Gluten and Cognitive Function Among US Women

IMPORTANCE

Gluten avoidance has been suggested as having a benefit to cognitive health among the general population, given the link between gluten and cognitive impairment in patients with celiac disease. However, data are lacking in individuals without celiac disease.

OBJECTIVE

To examine whether gluten intake is associated with cognitive function in women without celiac disease.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study included US women who participated in the longitudinal, population-based Nurses' Health Study II and had not previously or subsequently been diagnosed with celiac disease. Dietary data were collected from 1991 to 2015, and data on cognitive function were collected from 2014 to 2019. Data analysis was conducted from October 2020 to April 2021.

EXPOSURES

Energy-adjusted gluten intake, cumulatively averaged across questionnaire cycles prior to cognitive assessment.

MAIN OUTCOMES AND MEASURES

Three standardized cognitive scores assessed by the validated Cogstate Brief Battery: (1) psychomotor speed and attention score, (2) learning and working memory score, and (3) global cognition score. Higher scores indicated better performance.

RESULTS

The cohort included 13 494 women (mean [SD] age, 60.6 [4.6] years). The mean (SD) gluten intake was 6.3 (1.6) g/d. After controlling for demographic and lifestyle risk factors in linear regression, no significant differences in standardized cognitive scores (mean [SD], 0 [1]) by quintile of gluten intake were found across highest and lowest quintiles of gluten intake (psychomotor speed and attention: -0.02; 95% CI, -0.07 to 0.03; P for trend = .22; learning and working memory: 0.02; 95% CI, -0.03 to 0.07; P for trend = .30; global cognition: -0.002; 95% CI, -0.05 to 0.05; P for trend = .78). The null associations persisted after additional adjustment for major sources of dietary gluten (ie, refined grains or whole grains), comparing decile categories of gluten intake, using gluten intake updated at each previous questionnaire cycle, or modeling changes in gluten intake. Similarly, these associations were not materially altered in sensitivity analyses that excluded women who had reported cancer or dementia diagnosis or had not completed all dietary assessments.

CONCLUSIONS AND RELEVANCE

In this study, long-term gluten intake was not associated with cognitive scores in middle-aged women without celiac disease. Our results do not support recommendations to restrict dietary gluten to maintain cognitive function in the absence of celiac disease or established gluten sensitivity.

Dietary Patterns in Runners with Gastrointestinal Disorders

Individuals with inflammatory bowel disease (IBD), irritable bowel syndrome (IBS) and reflux frequently experience gastrointestinal symptoms (GIS), potentially enhanced by high-intensity running. Food avoidances, food choices, and GIS in runners with IBS/IBD (n = 53) and reflux (n = 37) were evaluated using a reliability and validity tested questionnaire. Comparisons to a control group of runners (n = 375) were made using a Fisher’s Exact test. Runners with IBS/IBD experienced the greatest amount of exercise-induced GIS followed by those with reflux. Commonly reported GIS were stomach pain/cramps (77%; 53%), bloating (52%; 50%), intestinal pain/cramps (58%; 33%), and diarrhea (58%; 39%) in IBS/IBD and reflux groups respectively. In the pre-race meal, those with IBS/IBD frequently avoided milk products (53%), legumes (37%), and meat (31%); whereas, runners with reflux avoided milk (38%), meat (36%), and high-fibre foods (33%). When considering food choices pre-race, runners with IBS/IBD chose grains containing gluten (40%), high fermentable oligo-, di-, mono-saccharides and polyols (FODMAP) fruits (38%), and water (38%). Runners with reflux chose water (51%), grains containing gluten (37%), and eggs (31%). In conclusion, while many runners with IBS/IBD and reflux are avoiding trigger foods in their pre-race meals, they are also consuming potentially aggravating foods, suggesting nutrition advice may be warranted.

Prevalence of Wheat/Gluten-Related Disorders and Gluten-Free Diet in Paraguay: An Online Survey-Based Study

Gluten-related disorders (GRDs) are increasing around the world, but their magnitude and relevance remain unknown in most Latin American countries. Thus, an online survey was conducted to estimate the prevalence of GRDs as well as adherence to a gluten-free diet (GFD) in Paraguayan adult population. There were 1058 individuals surveyed using a validated questionnaire (response rate of 93.9%). The self-reported prevalence rates were as follows (95% CI): gluten sensitivity (GS), 10.30% (8.53-12.29); non-celiac GS (NCGS), 5.19% (3.94-6.71); physician-diagnosed celiac disease (PD-CD), 3.11% (2.15-4.35); wheat allergy (WA), 2.07% (1.30-3.13); and adherence to GFD, 15.69% (13.55-18.02). Excluding CD, more women than men met the criteria for GRDs, adverse food reactions, and GFD (p < 0.05). Eight respondents reported the coexistence of NCGS with PD-CD and/or WA. Most cases on a GFD indicated medical/dietitian advice for following the diet (68.07%). Non-self-reported GS individuals indicated weight control (46.4%) and the notion that the GFD is healthier (20.2%) as the main motivations for following the diet. GRDs are not uncommon in Paraguayan adult population. It seems that there is awareness about GRDs and the GFD, but training about the diagnosis of GRDs is desirable because of the informed overlapping diagnoses of CD or WA with NCGS. Future studies involving face-to-face interviews are necessary.

Non-Celiac Gluten Sensitivity in the Context of Functional Gastrointestinal Disorders

Gluten-free diets are increasingly chosen in the Western world, even in the absence of a diagnosis of celiac disease. Around 10% of people worldwide self-report gluten-related complaints, including intestinal and extra-intestinal symptoms. In most cases, these subjects would be labeled as patients suffering from irritable bowel syndrome (IBS) who place themselves on a gluten-free diet even in the absence of celiac disease. In some instances, patients report a clear benefit by avoiding gluten from their diet and/or symptom worsening upon gluten reintroduction. This clinical entity has been termed non-celiac gluten sensitivity (NCGS). The symptoms referred by these patients are both intestinal and extra-intestinal, suggesting that similarly to functional gastrointestinal disorders, NCGS is a disorder of gut-brain interaction. It remains unclear if gluten is the only wheat component involved in NCGS. The mechanisms underlying symptom generation in NCGS remain to be fully clarified, although in the past few years, the research has significantly moved forward with new data linking NCGS to changes in gut motility, permeability and innate immunity. The diagnosis is largely based on the self-reported reaction to gluten by the patient, as there are no available biomarkers, and confirmatory double-blind challenge protocols are unfeasible in daily clinical practice. Some studies suggest that a small proportion of patients with IBS have an intolerance to gluten. However, the benefits of gluten-free or low-gluten diets in non-celiac disease-related conditions are limited, and the long-term consequences of this practice may include nutritional and gut microbiota unbalance. Here, we summarize the role of gluten in the clinical features, pathophysiology, and management of NCGS and disorders of gut-brain interaction.

The Prevalence of Celiac Disease in a Fracture Liaison Service Population

Celiac disease (CD) is a known risk factor for osteoporosis and fractures. The prevalence of CD in patients with a recent fracture is unknown. We therefore systematically screened patients at a fracture liaison service (FLS) to study the prevalence of CD. Patients with a recent fracture aged ≥ 50 years were invited to VieCuri Medical Center's FLS. In FLS attendees, bone mineral density (BMD) and laboratory evaluation for metabolic bone disorders and serological screening for CD was systematically evaluated. If serologic testing for CD was positive, duodenal biopsies were performed to confirm the diagnosis CD. Data were collected in 1042 consecutive FLS attendees. Median age was 66 years (Interquartile range (IQR) 15), 27.6% had a major and 6.9% a hip fracture, 26.4% had osteoporosis and 50.8% osteopenia. Prevalent vertebral fractures were found in 29.1%. CD was already diagnosed in two patients (0.19%), one still had a positive serology. Three other patients (0.29%) had a positive serology for CD (one with gastro-intestinal complaints). In two of them, CD was confirmed by duodenal histology (0.19%) and one refused further evaluation. The prevalence of biopsy-proven CD was therefore 0.38% (4/1042) of which 0.19% (2/1042) was newly diagnosed. The prevalence of CD in patients with a recent fracture at the FLS was 0.38% and within the range of reported prevalences in the Western-European population (0.33-1.5%). Newly diagnosed CD was only found in 0.19%. Therefore, standard screening for CD in FLS patients is not recommended.

Recent advances in diagnosis and management of irritable bowel syndrome

PURPOSE OF REVIEW

This review summarizes recent progress in the diagnosis and management of irritable bowel syndrome, with a focus on dietary and microbiota aspects.

RECENT FINDINGS

From a pathophysiological point of view, IBS is a multifactorial condition with both peripheral (transit) as central (visceral hypersensitivity, anxiety, depression) contribution in a cumulative fashion to the symptom pattern and severity. More recently, the focus has shifted to diet and microbiota. The number of dietary options that can be used for IBS and the understanding of determinants of their efficacy is rapidly increasing. Several studies have confirmed the efficacy of the low fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAP) diet. Sucrose-isomaltase deficiency has emerged as pathogenetic mechanisms in a subset of patients, who do not respond to low FODMAP diet but may respond to starch and sucrose elimination. Herbal remedies, probiotics and secretagogues have been the topic of additional treatment trials. The efficacy of fecal microbiota transplantation in IBS is variable across studies, but donor selection is emerging as a critical factor.

SUMMARY

Irritable bowel syndrome has evolved into a disorder of interaction between dietary factors and gut microbiota, with impact on bowel symptoms as well as extra-intestinal, central, symptoms. Dietary adjustments and treatments targeting the gut microbiota are areas of active research and clinical progress.

Brain fog and non-coeliac gluten sensitivity: Proof of concept brain MRI pilot study

AIMS

Non-Coeliac Gluten Sensitivity (NCGS) is poorly understood, particularly in terms of its neurological outcomes. We initially conducted a prospective postal survey to investigate its neurological presentation and symptom course. Results from this then motivated a follow-up pilot study utilising brain MRI to characterise potential diagnostic biomarkers for future research.

METHODS

Patients with NCGS were recruited from a specialist centre and completed a prospective postal questionnaire (N = 125). This summarised symptoms experienced, their severity and their course. Onset time was compared by Chi-squared analysis to data from the same centre concerning coeliac disease patients (N = 224). Five respondents on a strict gluten-free diet who self-reported brain fog then attended a pilot study, completing MR brain imaging/questionnaires before/after a gluten challenge. "Baseline" data were assessed for abnormalities, while symptom severity and cerebral blood flow (CBF) were compared before/after challenge.

RESULTS

Survey participants were aged 47 (85% female). Prevalence of neurological symptoms were: headaches (51%), brain fog (48%), balance issues (31%), tingling (19%). Median symptom resolution time was 48 hours, while onset was 90 minutes; onset pattern was not significantly different compared to CD patients (p = 0.322). Extra-intestinal symptoms worsened by 37%(±28) during a typical reaction. Predominantly non-statistical observations from the brain imaging study are discussed.

CONCLUSIONS

Neurological symptoms in NCGS are common, and onset time is comparable to that in CD. Brain imaging may be a useful future means of investigating physiological injury and responses to gluten in further study.

Pitfalls in the Diagnosis of Coeliac Disease and Gluten-Related Disorders

The spectrum of gluten-related disorders (GRD) has emerged as a relevant phenomenon possibly impacting on health care procedures and costs worldwide. Current classification of GRD is mainly based on their pathophysiology, and the following categories can be distinguished: immune-mediated disorders that include coeliac disease (CD), dermatitis herpetiformis (DH), and gluten ataxia (GA); allergic reactions such as wheat allergy (WA); and non-coeliac gluten sensitivity (NCGS), a condition characterized by both gastrointestinal and extra-intestinal symptoms subjectively believed to be induced by the ingestion of gluten/wheat that has recently gained popularity. Although CD, DH, and WA are well-defined clinical entities, whose diagnosis is based on specific diagnostic criteria, a diagnosis of NCGS may on the contrary be considered only after the exclusion of other organic disorders. Neither allergic nor autoimmune mechanisms have been found to be involved in NCGS. Mistakes in the diagnosis of GRD are still a relevant clinical problem that may result in overtreatment of patients being unnecessary started on a gluten-free diet and waste of health-care resources. On the basis of our clinical experience and literature, we aim to identify the main pitfalls in the diagnosis of CD and its complications, DH, and WA. We provide a practical methodological approach to guide clinicians on how to recognize and avoid them.

A Gluten Reduction Is the Patients' Choice for a Dietary 'Bottom Up' Approach in IBS-A Comment on "A 5Ad Dietary Protocol for Functional Bowel Disorders" Nutrients 2019, 11, 1938

We read the article by Ibrahim and Stribling [...].

Gluten-Free Products: From Dietary Necessity to Premium Price Extraction Tool

Every year, the Italian National Health Service (NHS) provides about 200,000 celiac people (based on 2017 data) living in Italy with financial support of about 250 million euro to cover the cost of their specific dietary constrains. The existence of gluten-free products of high quality and affordable price is very important for the quality of life of celiac people and the sustainability of public support. Over the last decade, the market for gluten-free products has experienced a dramatic surge, with an increasing shelf space dedicated to these products in supermarkets, and a large variety of products both in terms of kind of agricultural inputs and processing and packaging methods. This study aimed at assessing the offer of gluten-free (GF) pasta in Italian supermarkets, with respect to its ability to meet the needs of celiac people in terms of variety, prices and safety. A hedonic price analysis was performed. Results indicated that GF pasta is sold only in 44% of the 212 stores of the sample, with a price equal to more than twice that of conventional pasta. A premium price was found for the following attributes: small packages, brands specialized in GF products, content in fiber and the presence of quinoa as ingredient.