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The NED Journal - Male Health, ADHD and Neurodiversity, Stress and Adrenals
Issue 2_December 2023 Peer-reviewed expert reviews and clinical insights from the Nutrition Evidence Editorial Board and Expert Review Panel
2024
Abstract
In this 2nd edition of the NED Journal, you can read some of the latest expert insights on male health, ADHD and neurodiversity, and stress and adrenals. This NED Journal transforms the science to enable individualised science-based clinical decision making, with 14 peer-reviewed expert reviews. The NED Journal supports BANT members and other integrative and personalised medicine practitioners with their evidence-based practice.
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Effects of a low FODMAP diet on gut microbiota in individuals with treated coeliac disease having persistent gastrointestinal symptoms - a randomised controlled trial.
Herfindal, AM, van Megen, F, Gilde, MKO, Valeur, J, Rudi, K, Skodje, GI, Lundin, KEA, Henriksen, C, Bøhn, SK
The British journal of nutrition. 2023;130(12):2061-2075
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Coeliac disease (CeD) is a common immune-mediated disease where intolerance to gluten can lead to severe health problems with a wide range of gastrointestinal (GI) and extra-intestinal symptoms. Research shows that a diet low in fermentable oligo-, di-, mono-saccharides and polyols (FODMAP) helps to reduce GI symptoms in irritable-bowel syndrome and gluten-free diet treated CeD. The aim of this study was to investigate whether a low FODMAP diet (LFD) in this patient group affects (i) the faecal microbiota, (ii) the concentrations of faecal short-chain fatty acids (SCFA) and (iii) the concentrations of faecal human neutrophil gelatinase-associated lipocalin (a biomarker of gut inflammation). This study is part of a clinical trial which followed a nonblinded, parallel randomised design. The participants were randomised to either an LFD group or a control group. Results showed that after four weeks, certain differences in gut microbiota were detected between the control and LFD group. The SCFA results indicated that the LFD resulted in lower concentrations of propionic and valeric acid in participants with initially high concentrations. Biomarker of gut inflammation was, however, unaffected by the LFD. Authors conclude that the LFD led to changes in overall community structure of the faecal microbiota, with a possible unfavourable low faecal abundance of Anaerostipes, and low concentrations of the faecal SCFA propionic and valeric acid in participants with high concentrations of these acids at baseline.
Abstract
Individuals with coeliac disease (CeD) often experience gastrointestinal symptoms despite adherence to a gluten-free diet (GFD). While we recently showed that a diet low in fermentable oligo-, di-, monosaccharides and polyols (FODMAP) successfully provided symptom relief in GFD-treated CeD patients, there have been concerns that the low FODMAP diet (LFD) could adversely affect the gut microbiota. Our main objective was therefore to investigate whether the LFD affects the faecal microbiota and related variables of gut health. In a randomised controlled trial GFD-treated CeD adults, having persistent gastrointestinal symptoms, were randomised to either consume a combined LFD and GFD (n 39) for 4 weeks or continue with GFD (controls, n 36). Compared with the control group, the LFD group displayed greater changes in the overall faecal microbiota profile (16S rRNA gene sequencing) from baseline to follow-up (within-subject β-diversity, P < 0·001), characterised by lower and higher follow-up abundances (%) of genus Anaerostipes (Pgroup < 0·001) and class Erysipelotrichia (Pgroup = 0·02), respectively. Compared with the control group, the LFD led to lower follow-up concentrations of faecal propionic and valeric acid (GC-FID) in participants with high concentrations at baseline (Pinteraction ≤ 0·009). No differences were found in faecal bacterial α-diversity (Pgroup ≥ 0·20) or in faecal neutrophil gelatinase-associated lipocalin (ELISA), a biomarker of gut integrity and inflammation (Pgroup = 0·74), between the groups at follow-up. The modest effects of the LFD on the gut microbiota and related variables in the CeD patients of the present study are encouraging given the beneficial effects of the LFD strategy to treat functional GI symptoms (Registered at clinicaltrials.gov as NCT03678935).
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The Influence of Nutritional Intervention in the Treatment of Hashimoto's Thyroiditis-A Systematic Review.
Osowiecka, K, Myszkowska-Ryciak, J
Nutrients. 2023;15(4)
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Hashimoto’s thyroiditis is an autoimmune disorder characterized by the presence of antibodies in the thyroid gland such as thyroid peroxidase (TPO) and thyroglobulin (TG) antibodies. Immune-mediated inflammatory responses eventually lead to the progressive destruction of the gland and impaired thyroid function. The disease has a strong genetic disposition but is also influenced by environmental factors, including diet. Hence diet has been considered a complementary tool to manage thyroid function and disease progression by harnessing the benefits of certain nutrients and anti-inflammatory properties. This systematic review examined the effects of nutrients and dietary interventions on Hashimoto’s disease in current literature. Using antibody levels, thyroid hormone levels and body weight to measure outcomes. The review included 9 studies, all of which compared the intervention group to the control groups. The trials included looked at gluten-free, lactose-free and energy-restricted diets, with or without selected nutrients and foods supplements (ie. Nigella sativa, iodine). The intervention duration ranged from 3 weeks to 12 months. Despite the small number of trials, the data from those studies included in this review showed promising results. Improvements in disease parameters were observed in diets that were energy deficient, eliminated gluten, lactose and goitrogens or added Nigella sativa. Iodine restrictions did not show any improvements. In the discussion section, the authors presented the results in the wider context and the findings from other studies. Ultimately there appears to be a wide variance in outcomes, usually ranging from beneficial to neutral. The authors contributed to such variability due to the complexity of the condition and many influencing factors. Often participants in trials have highly variable thyroid status and function, and differences in regular dietary intakes of nutrients critical to thyroid health can easily distort the results. Hence much more specific research is needed to make firmer conclusions. Whereby no clear conclusions in larger groups could be drawn, potential benefits of dietary interventions in Hashimoto's disease may be much more apparent in clinical settings with personalized approaches that account for such individual variances.
Abstract
Diet can be a complementary treatment for Hashimoto's disease by affecting thyroid function and anti-inflammatory properties. It is still unclear which dietary strategy would be the most beneficial. The aim of this systematic review is to examine all the data currently available in the literature on the effects of nutritional intervention on biochemical parameters (anti-thyroid antibody and thyroid hormones levels) and characteristic symptoms in the course of Hashimoto's thyroiditis. This systematic review was prepared based on PRISMA guidelines. Articles in PubMed and Scopus databases published up to November 2022 were searched. As a result of the selection, out of 1350 publications, 9 were included for further analysis. The nutritional interventions included the following: elimination of gluten (3 articles) or lactose (1 article), energy restriction with or without excluding selected foods (n = 2), consumption of Nigella sativa (n = 2), or dietary iodine restriction (n = 1). The intervention duration ranged from 21 days to 12 months and included individuals with various thyroid function. Of the nine studies, three studies were female only. An improvement was observed during an energy deficit and after the elimination of selected ingredients (e.g., gluten, lactose, or goitrogens), as well as after the intervention of Nigella sativa. These interventions improved antibody levels against peroxidase (anti-TPO), (thyrotropin) TSH, and free thyroxine (fT4). No improvement was seen on the iodine-restricted diet. Varied outcomes of analyzed dietary interventions may be due to the heterogeneous thyroid condition, high variability between patients, and differences in habitual intake of critical nutrients (e.g., iodine, selenium, and iron) in different populations. Therefore, there is a great need for further experimental studies to determine whether any nutritional interventions are beneficial in Hashimoto's disease.
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Treating the Underlying Causes of Chronic Migraine
As the pioneer and global leader of Functional Medicine, the Institute of Functional Medicine (IFM) leads and catalyses the efforts of a large and expanding Functional Medicine ecosystem, including providers, educators, payers, industry leaders, regulators, and influencers.
2022
Abstract
Pinpointing the exact pathophysiology of migraines is challenging. This insight from the IFM looks at mitochondrial dysfunction, oxidative stress and gastrointestinal disorders as key players in the role of migraine development and progression. Research suggests that the prevalence of migraines can be increased with a number of gastrointestinal conditions such as helicobacter pylori infection, irritable bowel syndrome and coeliac disease. Nutrition interventions that have been shown to improve quality of life in chronic migraine sufferers includes the ketogenic diet and nutrient supplementation with riboflavin, CoQ10 and magnesium.
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The role of gut health in psoriasis
Alex Manos is one of the UK’s leading Functional Medicine practitioners who specialises in SIBO and gut-related disorders, as well as mould illness and mycotoxins. He is also very passionate about physical therapy, movement, resiliency, life coaching, nutritional therapy, and biohacking. He is a lecturer at various colleges and institutions including the Institute of Optimum Nutrition (ION) and on the MSc program at The Centre For Nutritional Education and Lifestyle Management (CNELM).
2022
Abstract
This is a really informative and concise presentation (with slides) from Alex summarising the research around the role of gut health in psoriasis. He covers dysbiosis, gut microbiome metabolites, gut inflammation, small intestinal bacterial overgrowth (SIBO), leaky gut and also coeliac and gluten sensitivity. He is quick to point out however that the gut is not the only thing that contributes to psoriasis, as there are many factors that can accumulate and contribute to psoriasis including infections, body composition, environmental toxins, medications, poor diet, and stress. He addresses testing options that are available to help determine which aspect of gut health could be targeted using nutrition and supplements to help alleviate the severity of psoriasis.
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The effect of gluten in adolescents and young adults with gastrointestinal symptoms: a blinded randomised cross-over trial.
Crawley, C, Savino, N, Halby, C, Sander, SD, Andersen, AN, Arumugam, M, Murray, J, Christensen, R, Husby, S
Alimentary pharmacology & therapeutics. 2022;55(9):1116-1127
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The gluten-free diet (GFD) has gained increasing popularity among healthy people without coeliac disease or wheat allergy. The main reasons for following a GFD are weight control, the perception that a GFD is healthier, and the presence of symptoms after gluten ingestion. The aim of this study was to address the hypothesis that adding gluten to the diet results in a self-reported worsening of gastrointestinal symptoms (primary outcome) and mental health (key secondary outcomes) in a well-characterised group of adolescents. This study was arranged in two phases; the first phase began with 2 weeks of a GFD, and if the participants responded to the GFD, they proceeded to phase 2. Phase 2 was a double-blinded randomised trial with cross-over and consisted of three periods, each lasting 7 days: (1) a challenge with gluten/placebo, (2) wash-out phase, and (3) the second challenge with placebo/gluten. Results show that it was not possible to detect a difference in symptoms between gluten and placebo at a group level. Furthermore, on an individual level, there was a comparable number of gluten responders and placebo responders, underscoring the insignificant difference between gluten and placebo. Authors conclude that adding gluten to the diet does not induce gastrointestinal symptoms or worsened mental health in adolescents.
Abstract
BACKGROUND The popularity of the gluten-free diet and sales of gluten-free products have increased immensely. AIMS To investigate whether gluten induces gastrointestinal symptoms, measured by self-reported questionnaires, as well as mental health symptoms in adolescents from a population-based cohort. METHODS The eligible participants (n = 273) were recruited from a population-based cohort of 1266 adolescents and had at least four different gastrointestinal symptoms. Phase one (n = 54) was a run-in phase where the participants lived gluten-free for 2 weeks. If they improved they continued to phase 2 (n = 33), a blinded randomised cross-over trial. Participants were blindly randomised either to start with 7 days of gluten, eating two granola bars containing 10 g of gluten or to 7 days on placebo, eating two granola bars without gluten, followed by the reverse and separated by a 7-day washout period. The effects of the intervention on gastrointestinal symptoms and mental health symptoms were assessed. RESULTS In total, 54/273 participants entered the run-in phase and 35 were eligible for randomization. A total of 33 were randomised and 32 completed the trial. The median age was 20.3 (IQR 19.2-20.9) and 32/33 participants were females. Compared with a placebo, gluten did not induce gastrointestinal symptoms. The difference in the average VAS was -0.01 (95% confidence interval -2.07 to 2.05). Nor did we find a difference in the outcomes measuring mental health. CONCLUSION Compared with placebo, adding gluten to the diet did not induce gastrointestinal symptoms or worsened mental health in adolescents recruited from a population-based cohort. The trial registration number is NCT04639921.
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Effect of ancient Khorasan wheat on gut microbiota, inflammation, and short-chain fatty acid production in patients with fibromyalgia.
Baldi, S, Pagliai, G, Dinu, M, Di Gloria, L, Nannini, G, Curini, L, Pallecchi, M, Russo, E, Niccolai, E, Danza, G, et al
World journal of gastroenterology. 2022;28(18):1965-1980
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Fibromyalgia (FM) is a systemic syndrome of unclear aetiology, characterized by widespread pain and tenderness, sleeping disorders, fatigue, and cognitive dysfunction. In many cases, gastrointestinal distress is also reported, suggesting a potential involvement of the gut microbiota (GM), as demonstrated by the frequent dysbiosis found in FM subjects. The aim of this study was to examine whether a replacement diet with ancient Khorasan wheat could influence the GM composition, the faecal molecular immune profile, and short-chain fatty acids (SCFAs) production in patients suffering fibromyalgia syndrome. This study was a randomised, double-blind crossover trial which enrolled patients with documented FM who consumed control wheat products or Khorasan wheat products for 8 weeks and then crossed over. Participants (n=20) were randomly assigned to one of the two groups. Results showed that: - both 8-week interventions did not significantly modify either the microbial composition and diversity or the SCFAs levels; - in terms of changes in microbial abundances produced by each dietary intervention, Khorasan wheat products (KD) did not result in modifications at any taxonomic level, whereas the controlled diet (CD) was associated with a significant increase of Turicibacter spp. [bacteria belonging to the phylum Firmicutes]; - faecal molecular inflammatory profile showed that CD resulted in an increased level of a particular anti-inflammatory marker, while no significant differences were reported after KD. Authors conclude that an ancient Khorasan wheat diet results in some beneficial GM compositional and functional modifications that positively correlate with an improvement of fibromyalgia symptomatology.
Abstract
BACKGROUND Fibromyalgia (FM) syndrome is mainly characterized by widespread pain, sleeping disorders, fatigue, and cognitive dysfunction. In many cases, gastrointestinal distress is also reported, suggesting the potential pathogenic role of the gut microbiota (GM). The GM is deeply influenced by several environmental factors, especially the diet, and recent findings highlighted significant symptom improvement in FM patients following various nutritional interventions such as vegetarian diet, low-fermentable oligosaccharides, disaccharides, monosaccharides, and polyols based diets, gluten-free diet, and especially an ancient grain supplementation. In particular, a recent study reported that a replacement diet with ancient Khorasan wheat led to an overall improvement in symptom severity of FM patients. AIM: To examine the effects of ancient Khorasan wheat on the GM, inflammation, and short-chain fatty acid production in FM patients. METHODS After a 2-wk run-in period, 20 FM patients were enrolled in this randomized, double-blind crossover trial. In detail, they were assigned to consume either Khorasan or control wheat products for 8 wk and then, following an 8-wk washout period, crossed. Before and after treatments, GM characterization was performed by 16S rRNA sequencing while the fecal molecular inflammatory response and the short-chain fatty acids (SCFAs) were respectively determined with the Luminex MAGPIX detection system and a mass chromatography-mass spectrometry method. RESULTS The Khorasan wheat replacement diet, in comparison with the control wheat diet, had more positive effects on intestinal microbiota composition and on both the fecal immune and SCFAs profiles such as the significant increase of butyric acid levels (P = 0.054), candidatus Saccharibacteria (P = 9.95e-06) and Actinobacteria, and the reduction of Enterococcaceae (P = 4.97e-04). Moreover, the improvement of various FM symptoms along with the variation of some gut bacteria after the Khorasan wheat diet have been documented; in fact we reported positive correlations between Actinobacteria and both Tiredness Symptoms Scale (P < 0.001) and Functional Outcome of Sleep Questionnaire (P < 0.05) scores, between Verrucomicrobiae and both Widespread Pain Index (WPI) + Symptom Severity scale (SS) (P < 0.05) and WPI (P < 0.05) scores, between candidatus Saccharibacteria and SS score (P < 0.05), and between Bacteroidales and Sleep-Related and Safety Behaviour Questionnaire score (P < 0.05). CONCLUSION The replacement diet based on ancient Khorasan wheat results in beneficial GM compositional and functional modifications that positively correlate with an improvement of FM symptomatology.
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The Association between ADHD and Celiac Disease in Children.
Gaur, S
Children (Basel, Switzerland). 2022;9(6)
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Untreated coeliac disease (CeD) can be accompanied by an array of neurological symptoms. Some of these symptoms are similar to those observed in attention deficit hyperactive disorder (ADHD), like an inability to focus, lack of mental alertness, physical under-activity and clinically measurable under-activity in particular brain regions. The mechanism of such symptoms is not fully understood but is thought to be linked to low-grade inflammation in the brain as a result of permeability in the gut and blood-brain barrier, which could contribute to the presentation of ADHD-like symptoms. CeD can persist for many years in seemingly healthy people (silent CeD) without gut symptoms. In this period, ADHD-like symptoms are particularly common and may be treatment resistant if not accompanied by a gluten-free diet Since 2015, there have been several studies showing an association between CeD and ADHD. This is an updated systematic review including 23 studies of children and young adults, which found an association between ADHD and CeD, in contrast to previous reviews that found no clear association. This review paid particular attention to the diagnostic criteria of ADHD and its subtypes, highlighting the need to examine the subtypes of ADHD in future studies. Specifically, the inattentive subtype may be a behavioural ADHD phenotype that could respond to a gluten-free diet. The authors advocate screening ADHD patients for CeD and encourage the consideration of non-neurological symptoms in the assessment of ADHD to identify potential CeD cases.
Expert Review
Conflicts of interest:
None
Take Home Message:
- There is an association between celiac disease (CeD) and attention deficit hyperactive disorder (ADHD).
- Some children with ADHD may respond well to gluten-free diet.
Evidence Category:
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A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
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B: Systematic reviews including RCTs of limited number
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C: Non-randomized trials, observational studies, narrative reviews
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D: Case-reports, evidence-based clinical findings
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E: Opinion piece, other
Summary Review:
This systematic review explored the association between coeliac disease (CeD) and attention deficit hyperactive disorder (ADHD).
Methods
The review was conducted following the PRISMA reporting guidelines.
Inclusion criteria for the search:
- Search terms of ADHD and CeD
- Participants < 18 years.
52 papers were retrieved and screened
23 met inclusion/exclusion criteria
Results
- 13 studies (out of the 23) demonstrated an association between ADHD and CeD
- Most studies reporting a positive association were published post 2015
- The largest study reported (112,240 patients with CeD) demonstrates that ADHD showed an association of OR = 1.75 in in CeD.
- The study was limited by several factors including study design of the studies included in the review, which were mostly observational and some without control.
The author declares no conflict of interest.
Clinical practice applications:
- Evidence from across the literature suggests that children with untreated or newly diagnosed CeD may find that following a gluten-free diet can help improve some symptoms associated with ADHD
- The author suggests that there may be a behavioural phenotype of ADHD that responds to a gluten-free diet. If this is the case, it suggests that screening of ADHD patients for celiac disease may be important.
Considerations for future research:
- The number of studies were relatively small and varied in design. Further large-scale studies would help further inform the understanding of the association and potential therapeutic benefits of gluten-free diet.
- It would be interesting to further explore how different subtypes of ADHD, especially the inattentive subtype, may be associated with CeD.
- In particular, it might be useful to consider how the clinical construct of sluggish cognitive tempo (SCT) is associated, since SCT symptoms overlap with the neurological manifestations of CeD.
Abstract
UNLABELLED Controversy around the association between celiac disease (CeD) and attention deficit hyperactive disorder (ADHD) was addressed by a systematic review in 2015, ultimately showing no association. Since 2015, there have been several studies showing an association between celiac disease and attention deficit hyperactive disorder. This is an updated systematic review. BACKGROUND Most experts agree on the recommendation to not screen as part of the standard of care for ADHD in persons with CeD or vice versa. Simultaneously, they propose that untreated patients with CeD and neurological symptoms such as chronic fatigue, inattention, pain, and headache could be predisposed to ADHD-like behavior, namely inattention (which may be alleviated by following a gluten-free diet). The inattentive subtype of ADHD that encompasses the symptoms of inattention is phenotypically heterogeneous, as it includes the clinical construct of sluggish cognitive tempo (SCT). SCT symptoms overlap with the neurological manifestations of CeD. METHODS A systematic search (PRISMA) of PubMed, Google Scholar, EMBASE, Web of Science, Stanford Lane, SCOPUS, and Ovid was conducted for articles up to 21 February 2022. Of these, 23 studies met the criteria. RESULTS Out of the 23 studies, 13 showed a positive association between ADHD and CeD. Most studies that showed a positive association had been published in the last five years. Inconsistencies in the results remain due to the heterogeneous methodology used, specifically for ADHD and the outcome questionnaires, as well as a lack of reporting on ADHD subtypes. CONCLUSION There is an association between ADHD and celiac disease. The current methodological limitations will be lessened if we examine the subtypes of ADHD.
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Organic food consumption and gluten-free diet, is there a link? Results in French adults without coeliac disease.
Perrin, L, Allès, B, Julia, C, Hercberg, S, Touvier, M, Lairon, D, Baudry, J, Kesse-Guyot, E
The British journal of nutrition. 2021;125(9):1067-1078
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The gluten-free diet (GFD) is a medical response for people with coeliac disease, a systemic autoimmune disorder for which GFD is the only available effective treatment. The aim of this study was to compare the consumption of organic products (as a whole and by food group) in individuals (partially or totally) avoiding gluten or not, and their places of food purchases of organic food. Results indicate a positive association between gluten avoidance and contribution of organic food to the diet. A gradient was also observed with total avoiders consuming more of organic food than partial avoiders. This contribution was higher for all types of products, except milk and dairy products. Furthermore, the results appear consistent with the motives reported by individuals avoiding gluten. Authors conclude that their findings underline a strong positive correlation between gluten avoidance and organic food consumption.
Abstract
The rising popular belief that gluten is unhealthy has led to growth in gluten avoidance in people without coeliac disease. Little information is available on their dietary profiles and their dietary behaviours. Our aim was to compare the consumption of organic foods between gluten avoiders and non-avoiders, and their places of food purchase. We described their sociodemographic and dietary profiles. The study population included participants of the NutriNet-Santé cohort who completed both a food exclusion questionnaire and an organic semi-quantitative FFQ (n 23 468). Food intake and organic food consumption ratios were compared using multivariable adjusted ANCOVA models. Associations between gluten avoidance and organic food consumption as well as places of food purchase were investigated with multivariable logistic regression. Participants avoiding gluten were more likely to be women and had a healthier dietary profile. Organic food consumption was higher among gluten avoiders (48·50 % of total diet for total avoiders, 17·38 % for non-avoiders). After adjustments for confounders, organic food consumption and purchase in organic stores were positively associated with gluten avoidance: adjusted OR (aOR)Q5 v.Q1 organic food = 4·95; 95 % CI 3·70, 6·63 and aORorganic stores v.supermarkets = 1·82; 95 % CI 1·42, 2·33 for total avoiders. Our study highlights that individuals avoiding gluten are high organic consumers and frequently purchase their foods in organic stores which propose an extended offer of gluten-free food. Further research is needed to determine the underlying common motivations and the temporality of the dietary behaviours of healthy people avoiding gluten.
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Gluten and FODMAPs Relationship with Mental Disorders: Systematic Review.
Aranburu, E, Matias, S, Simón, E, Larretxi, I, Martínez, O, Bustamante, MÁ, Fernández-Gil, MDP, Miranda, J
Nutrients. 2021;13(6)
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There is growing evidence that gluten and FODMAPs, such as fermentable oligosaccharides, disaccharides, monosaccharides and polyols, can cause gastrointestinal symptoms, inflammation, and immune responses in patients with celiac disease and irritable bowel syndrome. In addition, a high intake of gluten and FODMAPs may also be associated with neurological and psychiatric disorders. Thirteen studies were included in this systematic review to examine the relationship between gluten and FODMAP consumption and illnesses affecting the central nervous system. In addition, the studies examined the effects of potential dietary strategies that consider gluten and FODMAP intake on mental disorders, anxiety, depression, schizophrenia, Alzheimer’s disease, and autism spectrum disorders. Several possible mechanisms identified in this systematic review could contribute to neurological and psychiatric disorders, including the release of proinflammatory cytokines, immune responses, gut dysbiosis, intestinal permeability, and interactions between the gut-brain axis. In patients with fibromyalgia, celiac disease, and irritable bowel syndrome, avoiding or limiting gluten may reduce depression, anxiety, and cognitive impairment. However, the effects of a low-FODMAP diet on the central nervous system are inconclusive. There is some evidence that gluten-free diets can improve cognition in schizophrenia patients. In addition, those with autism spectrum disorders may benefit from a gluten-free diet and a low-FODMAP diet. Further robust research is required to evaluate the beneficial effects of interventions that avoid or restrict the consumption of foods high in FODMAPs and gluten. However, healthcare professionals can use the results of this systematic review to understand the potential benefits of therapeutic interventions that consider the intake of FODMAPs and gluten on illnesses affecting the central nervous system and their possible mechanisms of action.
Abstract
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.