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Randomised controlled trial: effects of gluten-free diet on symptoms and the gut microenvironment in irritable bowel syndrome.
Algera, JP, Magnusson, MK, Öhman, L, Störsrud, S, Simrén, M, Törnblom, H
Alimentary pharmacology & therapeutics. 2022;56(9):1318-1327
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The majority of irritable bowel syndrome (IBS) patients relate their symptoms to intake of certain foods. The gut microenvironment, where microbiota, food components and the nervous system interact, is suggested to play a key role in gastrointestinal (GI) symptom generation in a subset of IBS patients. The main aim of this study was to assess and compare the efficacy of the gluten-free and gluten-containing diets in terms of effects on GI symptoms in IBS patients. Secondary aims where to identify the putative link between gut microenvironment and the diets´ effect on GI symptoms, and to identify potential predictors of clinical response to the gluten-free diet. This study is a single-centre, double-blind, randomised, placebo-controlled, cross-over trial. Adult sex- and age-matched IBS patients (n=20) and healthy controls (HC) (n=21) were recruited, randomised and challenged with gluten (14 g/day) and rice flour, both for 2 weeks, while adhering to a strict gluten-free diet. Results indicate that a gluten-free diet may affect IBS symptoms in general, and bowel habits in a subset of IBS patients. The gluten-free diet has distinct effect on the gut microenvironment in IBS patients who respond favourably to gluten reduction. Authors conclude that the gut microenvironment may be of importance in the clinical response to the gluten-free diet in IBS, and future studies should aim to further assess these factors in relation to clinical response to the gluten-free diet.
Abstract
BACKGROUND A gluten-free diet reduces symptoms in some patients with irritable bowel syndrome (IBS) through unclear mechanisms. AIMS To assess the effects of gluten-free versus gluten-containing diet on symptoms and the gut microenvironment, and to identify predictors of response to the gluten-free diet in IBS METHODS Twenty patients with IBS and 18 healthy controls (HC) followed a gluten-free diet during two 14-day intervention periods where they sprinkled either gluten (14 g/day) or rice flour powder over their meals. Primary outcomes included effects of the interventions on IBS symptoms (IBS-SSS) and bowel habits. Secondary outcomes included effects of gluten-free diet on faecal microbiota and metabolite profile. RESULTS IBS symptoms improved during the gluten-free (p = 0.02), but not the gluten-containing period, with no difference between the interventions. IBS patients reported fewer loose stools during the gluten-free intervention (p = 0.01). Patients with IBS and HC presented distinct metabolite profiles based on the effects of the gluten-free diet (p < 0.001). True responders (reduced IBS-SSS by ≥50 solely after gluten-free period) and non-responders were discriminated based on the effects of the gluten-free diet on the microbiota (p < 0.01) and metabolite profiles (p < 0.001). The response to the gluten-free diet could be predicted by the metabolite profile before the intervention (p < 0.001). CONCLUSIONS A gluten-free diet may influence symptoms in a subset of patients with IBS, with a particular effect on bowel habits. A gluten-free diet seems to impact the gut microenvironment. Responsiveness to the gluten-free diet may be predicted by the metabolite profile. CLINICALTRIALS gov: NCT03869359.
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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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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.
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Dietary Patterns and Interventions to Alleviate Chronic Pain.
Dragan, S, Șerban, MC, Damian, G, Buleu, F, Valcovici, M, Christodorescu, R
Nutrients. 2020;12(9)
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A common symptom of many conditions is pain, with chronic pain being a significant cause of emotional distress and disability. Chronic pain is associated with a pro-inflammatory state. Diet interventions can be a helpful tool for the management of chronic pain and its associated inflammation. The increase of nutrient-dense, antioxidant-rich foods and the reduction of pro-inflammatory foods, as well as correcting nutrient deficiencies, all appear to have a positive effect on pain. Whilst previous research on the impact of diet therapy in chronic pain yielded varied results, the authors of this article sought to analyse the most important literature to gain more clarity and direction for future research. After a detailed introduction on the different types of pain, the article summarises the outcome of a range of dietary interventions for chronic pain management. These include calorie restriction and fasting, polyunsaturated fatty acids, low-fat plant-based diets, high protein diet, elimination diet, antioxidants and vitamins including vitamin D, fruits and fibres, prebiotics and probiotics. In the discussion, a helpful table presents the key results organised by type of pain (chronic musculoskeletal pain, chronic headache, neuropathic pain, chronic abdominal pain) and the clinical interventions that showed positive outcomes. In conclusion, diet interventions could be part of a multidisciplinary approach in the management of chronic pain. This article yields an oversight of the possible interventions to consider when supporting people with different types of chronic pain.
Abstract
Pain is one of the main problems for modern society and medicine, being the most common symptom described by almost all patients. When pain becomes chronic, the life of the patients is dramatically affected, being associated with significant emotional distress and/or functional disability. A complex biopsychosocial evaluation is necessary to better understand chronic pain, where good results can be obtained through interconnected biological, psychological, and social factors. The aim of this study was to find the most relevant articles existent in the PubMed database, one of the most comprehensive databases for medical literature, comprising dietary patterns to alleviate chronic pain. Through a combined search using the keywords "chronic pain" and "diet" limited to the last 10 years we obtained 272 results containing the types of diets used for chronic pain published in the PubMed database. Besides classical and alternative methods of treatment described in literature, it was observed that different diets are also a valid solution, due to many components with antioxidant and anti-inflammatory qualities capable to influence chronic pain and to improve the quality of life. Thirty-eight clinical studies and randomized controlled trials are analyzed, in an attempt to characterize present-day dietary patterns and interventions to alleviate chronic pain.
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You Are What You Eat-The Relationship between Diet, Microbiota, and Metabolic Disorders-A Review.
Moszak, M, Szulińska, M, Bogdański, P
Nutrients. 2020;12(4)
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The gut microbiota (GM) is a collection of microorganisms living in the digestive tract of humans, which if unbalanced, may have a role in the development of certain disorders such as type 2 diabetes and obesity. A number of factors can imbalance the gut microbiota, one of the main being diet. This review paper of 190 papers aimed to summarise the relationship between GM, diet and modifiable diseases such as type 2 diabetes and obesity. Dietary components and the role of carbohydrates, protein and fats in shaping the GM were discussed. It was determined that carbohydrates have the greatest influence, with simple carbohydrates such as the sugars fructose and sucrose having a negative impact and the more complex forms being beneficial. Diet types were also reviewed. Vegetarian and vegan diets appear to increase the diversity of the GM, the Mediterranean diet changes the species balance, and the Western diet imbalances the GM causing diseases such as heart disease. Interestingly the literature points towards a negative impact of the gluten free diet. Diseases such as type 2 diabetes, obesity and increased fats in the blood all display an imbalanced GM causing increased energy harvest from food and disruption of various energy pathways in the body. It was concluded that a balanced diet rich in fruit, vegetables, fibre and healthy fats can promote GM diversity and activity. This study could be used by health care professionals to understand the importance of certain dietary components to promote GM diversity in order to reduce the risk of diseases such as obesity and type 2 diabetes.
Abstract
The gut microbiota (GM) is defined as the community of microorganisms (bacteria, archaea, fungi, viruses) colonizing the gastrointestinal tract. GM regulates various metabolic pathways in the host, including those involved in energy homeostasis, glucose and lipid metabolism, and bile acid metabolism. The relationship between alterations in intestinal microbiota and diseases associated with civilization is well documented. GM dysbiosis is involved in the pathogenesis of diverse diseases, such as metabolic syndrome, cardiovascular diseases, celiac disease, inflammatory bowel disease, and neurological disorders. Multiple factors modulate the composition of the microbiota and how it physically functions, but one of the major factors triggering GM establishment is diet. In this paper, we reviewed the current knowledge about the relationship between nutrition, gut microbiota, and host metabolic status. We described how macronutrients (proteins, carbohydrates, fat) and different dietary patterns (e.g., Western-style diet, vegetarian diet, Mediterranean diet) interact with the composition and activity of GM, and how gut bacterial dysbiosis has an influence on metabolic disorders, such as obesity, type 2 diabetes, and hyperlipidemia.
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The Differences between Gluten Sensitivity, Intestinal Biomarkers and Immune Biomarkers in Patients with First-Episode and Chronic Schizophrenia.
Dzikowski, M, Juchnowicz, D, Dzikowska, I, Rog, J, Próchnicki, M, Kozioł, M, Karakula-Juchnowicz, H
Journal of clinical medicine. 2020;9(11)
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Schizophrenia is a heterogeneous neuroimmune disorder with unknown mechanisms and aetiology. The goal of this clinical study was to compare and evaluate IgG and IgA sensitivity, inflammation, and gut integrity between 52 first episode Schizophrenia patients, 50 chronic Schizophrenia patients, and 60 healthy controls to explain whether there were any associations between these markers. Study results show that antigliadin IgG and IgA antibodies, as well as inflammatory markers such as hs-CRP and IL-6, were significantly higher in the first episodes of schizophrenia and chronic schizophrenia patients when compared to the healthy controls. Schizophrenia risk was 4-7% higher among those with elevated Antigliadin IgG and IgA antibody levels. In addition, smoking cigarettes has been shown to increase the risk of developing schizophrenia. Patients with chronic schizophrenia showed elevated levels of anti-Saccharomyces cerevisiae antibody and soluble CD14, indicating bacterial translocation and immune activation. To understand the mechanisms behind chronic Schizophrenia, which link inflammation, immune responses, and the gut-brain axis, further robust larger studies are necessary. The results of this study can be used by healthcare professionals to understand the relationship between intestinal permeability, inflammation, and food hypersensitivity.
Abstract
Schizophrenia is a heterogeneous disorder without a fully elucidated etiology and mechanisms. One likely explanation for the development of schizophrenia is low-grade inflammation, possibly caused by processes in the gastrointestinal tract related to gluten sensitivity. The aims of this study were to: (1) compare levels of markers of gluten sensitivity, inflammation and gut permeability, and (2) determine associations between gluten sensitivity, inflammation, and intestinal permeability in patients with first-episode/chronic (FS/CS) schizophrenia and healthy individuals (HC). The total sample comprised 162 individuals (52 FS; 50 CS, and 60 HC). The examination included clinical variables, nutritional assessment, and serum concentrations of: high-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), soluble CD14 (sCD14), anti-Saccharomyces cerevisiae antibody (ASCA), antigliadin antibodies (AGA) IgA/IgG, antibodies against tissue transglutaminase 2 (anti-tTG) IgA, anti-deamidated gliadin peptides (anti-DGP) IgG. A significant difference between groups was found in sCD14, ASCA, hs-CRP, IL-6 and AGA IgA levels. AGA IgG/IgA levels were higher in the FS (11.54%; 30.77%) and CS (26%; 20%) groups compared to HC. The association between intestinal permeability and inflammation in the schizophrenic patients only was noted. The risk for developing schizophrenia was odds ratio (OR) = 4.35 (95% confidence interval (CI 1.23-15.39) for AGA IgA and 3.08 (95% CI 1.19-7.99) for positive AGA IgG. Inflammation and food hypersensitivity reactions initiated by increased intestinal permeability may contribute to the pathophysiology of schizophrenia. The immune response to gluten in FS differs from that found in CS.
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The Neuropathology of Gluten-Related Neurological Disorders: A Systematic Review.
Rouvroye, MD, Zis, P, Van Dam, AM, Rozemuller, AJM, Bouma, G, Hadjivassiliou, M
Nutrients. 2020;12(3)
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Coeliac disease (CD) is an autoimmune disorder triggered by the ingestion of gluten in genetically susceptible individuals. A wide range of extraintestinal manifestations has been attributed to CD, changing the classic perception of a disease limited to the intestine, to a multisystem disorder. The aim of this study was to analyse the published neuropathology of confirmed cases of gluten-related neurological dysfunction to aid our understanding of the pathogenesis. CD can therefore manifest with dental problems, consequences of malabsorption, skin and neurological disorders. This study is a systematic review of thirty-two neurological disorder focused studies. Results show that: - the neuropathological findings in gluten-related neurological disorders are widespread and not limited to the cerebellum. - the pathology is immune mediated and not related to vitamin or trace elements deficiencies. - the pathophysiology of neurological damage in the context of gluten sensitivity has an immune mediated basis. - more gluten-related neurological disorders affected men (57%), which was even higher in the ataxia group (76%). - transglutaminase 6 antibodies might be helpful in the diagnostic workup of gluten-related neurological disorders. Authors conclude that the current evidence is suggestive of both humoral and cell-mediated immunological responses. Further research is required to investigate the underlying neuropathological mechanism by characterisation of the inflammatory cell infiltrate and identification of target epitopes.
Abstract
Gluten-related neurological disorders (GRND) represent a spectrum of neurological manifestations that are triggered by gluten. In coeliac disease, a T-cell mediated enteropathy is triggered by gluten in genetically predisposed individuals. The underlying pathological mechanism of the neurological dysfunction is not yet clear. The aim of this review is to collate existing neuropathological findings in GRND as a means of aiding the understanding of the pathophysiology. A systematic search of the Pubmed Database yielded 188 articles, of which 32 were included, containing 98 eligible cases with a description of pathological findings in GRND. In gluten ataxia, loss of Purkinje cells, atrophy, gliosis and astrocytosis were apparent, as well as diffuse lymphocytic infiltration and perivascular cuffing with lymphocytes. In patients with large-fiber neuropathy, nerve biopsies revealed axonopathy, loss of myelinated fibers and focal and perivascular infiltration by inflammatory cells. Inflammatory infiltrate was also observed in muscle in myopathy and in cerebrum of patients with encephalopathy and patients with epilepsy. Such changes were not seen in skin biopsies from patients with small fiber neuropathies. The findings from this systematic review suggest an immune mediated pathogenesis for GRND. Future research should focus on the characterization of the inflammatory cell infiltrates and identifying target epitopes.
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A Gluten Free Diet in the Management of Epilepsy in People with Coeliac Disease or Gluten Sensitivity
BANT members Zoe Gilbey and Justine Bold published in MDPI Gastrointestional Disorders
2020
Abstract
A systematic literature review to assess the effects of a gluten free diet in the management of epilepsy in people with coeliac disease or gluten sensitivity.
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Dietary interventions in fibromyalgia: a systematic review.
Silva, AR, Bernardo, A, Costa, J, Cardoso, A, Santos, P, de Mesquita, MF, Vaz Patto, J, Moreira, P, Silva, ML, Padrão, P
Annals of medicine. 2019;51(sup1):2-14
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Fibromyalgia is a long-term health condition causing widespread pain and is often accompanied by other symptoms such as extreme tiredness, headaches and irritable bowel syndrome (IBS). Several different dietary approaches have shown some potential in reducing the symptoms of fibromyalgia. In this meta-analysis, researchers looked at seven previous trials that examined five different dietary approaches: low-calorie; low FODMAPs (fermentable oligo-, di-, monosaccharides and polyols); gluten-free; vegan; and a monosodium glutamate (MSG) and aspartame-free diet. Pain and function improved with the low calorie diet, a raw vegan diet and the low FODMAPs diet. Other outcomes, such as quality of life, quality of sleep, anxiety and depression and inflammation also showed a significant improvement with these interventions. However, all of the studies were of low quality, and whilst there were some promising results, there is not currently enough evidence to recommend any of these dietary approaches. More well-designed clinical trials are needed on the effects of dietary approaches on fibromyalgia symptoms.
Abstract
Fibromyalgia (FM) is a chronic non-degenerative disease, whose nutritional therapy seems controversial. This systematic review aimed to synthesize the knowledge about the effect of dietary interventions on patient-reported outcomes (PRO) and inflammation in patients with FM. Six electronic databases - PubMed, BioMed Central, Cochrane library, EMBASE, LILACS and ISI - were searched for clinical trials, in which a dietary intervention in patients with FM diagnosed was conducted. Quality of evidence assessment was measured in accordance with GRADE methodology. Seven clinical trials - 3 randomized controlled trials, 1 unrandomized clinical trial and 3 uncontrolled clinical trials were identified. Dietary approaches included gluten-free diet (n = 1), raw vegetarian diet (n = 2), low Fermentable oligo-, di- and monossacharides, alcohols and polyols (FODMAPs) diet (n = 1), hypocaloric diet (n = 2) and monosodium glutamate- and aspartame-free diet interventions (n = 1). The major PRO were pain and functional repercussion, with 5 out of 7 studies reporting an improvement. The progress in secondary outcomes was reported for fatigue (2/5 studies), sleep quality (2/3 studies), depression and anxiety (3/6 studies), quality of life (4/5 studies), gastrointestinal symptoms (1/2 studies) and inflammatory biomarkers (1/1 study). However, according to Cochrane Risk of Bias, these studies had poor statistical quality. Well-designed studies should be performed to investigate the dietary interventions effect on FM. Key messages Fibromyalgia (FM) is a chronic non-degenerative disease, whose nutritional therapy seems controversial but promising. Pain and functional repercussion in FM patients seem to improve with a hypocaloric diet, a raw vegetarian diet or a low FODMAPs diet, as much as quality of life, quality of sleep, anxiety and depression and inflammatory biomarkers. Existing studies in this subject are scarce and low quality, which does not allow conclusions to be drawn.