The Role of Prebiotics in Modulating Gut Microbiota: Implications for Human Health.

The human gut microbiota, an intricate ecosystem within the gastrointestinal tract, plays a pivotal role in health and disease. Prebiotics, non-digestible food ingredients that beneficially affect the host by selectively stimulating the growth and/or activity of beneficial microorganisms, have emerged as a key modulator of this complex microbial community. This review article explores the evolution of the prebiotic concept, delineates various types of prebiotics, including fructans, galactooligosaccharides, xylooligosaccharides, chitooligosaccharides, lactulose, resistant starch, and polyphenols, and elucidates their impact on the gut microbiota composition. We delve into the mechanisms through which prebiotics exert their effects, particularly focusing on producing short-chain fatty acids and modulating the gut microbiota towards a health-promoting composition. The implications of prebiotics on human health are extensively reviewed, focusing on conditions such as obesity, inflammatory bowel disease, immune function, and mental health. The review further discusses the emerging concept of synbiotics-combinations of prebiotics and probiotics that synergistically enhance gut health-and highlights the market potential of prebiotics in response to a growing demand for functional foods. By consolidating current knowledge and identifying areas for future research, this review aims to enhance understanding of prebiotics' role in health and disease, underscoring their importance in maintaining a healthy gut microbiome and overall well-being.

Dietary Fiber in Inflammatory Bowel Disease: Are We Ready to Change the Paradigm?

Accumulating evidence from pre-clinical and clinical studies demonstrate the benefit of dietary fibers for inflammatory bowel disease (IBD). However, the majority of patients avoid or limit their consumption to manage their symptoms during the active and remission phases, although limited research supports these long-term dietary habits. Although recent evidence-based dietary guidelines highlight the importance of promoting an adequate intake of dietary fiber in IBD patients, intervention trials have not yet clearly clarified the quality and quantity of dietary fiber that should be consumed to be equally tolerated by and provide benefit for patients with IBD. This narrative review describes dietary fibers and their characteristics, analyzes the real-word studies on the impact of dietary fiber consumption in IBD in different clinical settings, and concludes with potential future directions in fiber research, focusing on the real-world needs of characterizing the consumption of fiber-rich foods and promoting their adequate intake.

Dietary therapies for adult and pediatric inflammatory bowel disease.

Diet is an environmental exposure implicated in the development of inflammatory bowel disease (IBD), including Crohn's disease (CD) and ulcerative colitis (UC). Dietary therapy is also a tool for management of these conditions. Nutrition therapy for IBD has been shown to reduce intestinal inflammation, promote healing, and alleviate symptoms, as well as improve patients' nutrition status. Although the mechanisms of action of most nutrition therapies for IBD are not well understood, the diets are theorized to eliminate triggers for gut dysbiosis and mucosal immune dysfunction associated with the typical Western diet. Exclusive enteral nutrition and the Crohn's disease exclusion diet are increasingly being used as the primary treatment modality for the induction of remission and/or maintenance therapy in children, and in some adults, with CD. Several other diets, such as the Mediterranean diet, anti-inflammatory diet for IBD, and diets excluding gluten, FODMAPs (fermentable oligosaccharides, disaccharides, monosaccharides, and polyols), lactose, or other compounds, may be helpful in symptom management in both CD and UC, though evidence for biochemical efficacy is limited. In this review, we discuss the role of diet components in IBD pathogenesis and examine diets currently used in the management of children and adults with IBD. We also address practical, psychosocial, and cultural considerations for dietary therapy across diverse populations.

Randomized controlled trial of hydrolyzed fish diets in dogs with chronic enteropathy.

BACKGROUND: The role of diet in the pathogenesis and treatment of chronic enteropathies (CE) in dogs is unresolved. OBJECTIVES: To compare the ability of diets composed of hydrolyzed fish, rice starch, and fish oil without (HF) or with prebiotics, turmeric, and high cobalamin (HF+) against a limited ingredient diet containing mixed nonhydrolyzed antigens and oils (control) to resolve clinical signs and maintain serum cobalamin and folate concentrations in dogs with nonprotein losing CE (non-PLE). To determine the ability of hydrolyzed fish diets to support recovery and remission in dogs with PLE. ANIMALS: Thirty-one client-owned dogs with CE: 23 non-PLE, 8 PLE. METHODS: Randomized, blinded, controlled trial. Diets were fed for 2 weeks; responders continued for 12 weeks. Nonresponders were crossed over to another diet for 12 weeks. Response was determined by standardized clinical evaluation with long-term follow-up at 26 weeks. Concurrent medications were allowed in PLE. RESULTS: Nineteen of 23 (83%; 95% confidence interval [CI], 60%-94%) non-PLE CE responded clinically to their initial diet, with no difference between diets (P > .05). Four nonresponders responded to another diet, with sustained remission of 18/18 (100%; 95%CI, 78%-100%) at 26 weeks. Serum cobalamin concentration was increased (P < .05) and maintained by diet. Serum folate concentration decreased posttreatment (P < .05) but was restored by dietary supplementation. Hydrolyzed fish diets supported weight gain, serum albumin concentration, and recovery (P < .05) in dogs with PLE. CONCLUSIONS AND CLINICAL IMPORTANCE: Changing diet, independent of antigen restriction or supplemental ingredients, induced long-term remission in dogs with non-PLE CE. Serum cobalamin and folate concentrations were maintained by diet. Hydrolyzed fish diets supported clinical recovery and remission in PLE.

Personalized Research on Diet in Ulcerative Colitis and Crohn's Disease: A Series of N-of-1 Diet Trials.

INTRODUCTION: Evidence about specific carbohydrate diet (SCD) for inflammatory bowel disease (IBD) is limited. We conducted 54 single-subject, double-crossover N-of-1 trials comparing SCD with a modified SCD (MSCD) and comparing each with the participant's baseline, usual diet (UD). METHODS: Across 19 sites, we recruited patients aged 7-18 years with IBD and active inflammation. Following a 2-week baseline (UD), patients were randomized to 1 of 2 sequences of 4 alternating 8-week SCD and MSCD periods. Outcomes included fecal calprotectin and patient-reported symptoms. We report posterior probabilities from Bayesian models comparing diets. RESULTS: Twenty-one (39%) participants completed the trial, 9 (17%) completed a single crossover, and 24 (44%) withdrew. Withdrawal or early completion occurred commonly (lack of response [n = 11], adverse events [n = 11], and not desiring to continue [n = 6]). SCD and MSCD performed similarly for most individuals. On average, there was <1% probability of a clinically meaningful difference in IBD symptoms between SCD and MSCD. The average treatment difference was -0.3 (95% credible interval -1.2, 0.75). There was no significant difference in the ratio of fecal calprotectin geometric means comparing SCD and MSCD (0.77, 95% credible interval 0.51, 1.10). Some individuals had improvement in symptoms and fecal calprotectin compared with their UD, whereas others did not. DISCUSSION: SCD and MSCD did not consistently improve symptoms or inflammation, although some individuals may have benefited. However, there are inherent difficulties in examining dietary changes that complicate study design and ultimately conclusions regarding effectiveness.

Diets for inflammatory bowel disease: What do we know so far?

In recent years, the role of diet in the pathogenesis of inflammatory bowel disease (IBD) has gained great interest within the scientific community. Eating habits from industrialised countries (the so-called western diet or WD) have been associated with a higher incidence of IBD in observational studies, although the dietary factors responsible for the development of the disease are still to be elucidated. Some components of the diet with proinflammatory potential may cause changes in immunity and intestinal microbiota, leading to the inflammatory reaction that causes IBD-related lesions. The quality of available evidence is low, due to methodological issues, such as the lack of intervention studies, small sample size and heterogeneity of studies. For this reason, scientific societies have offered their recommendations using clinical practice guidelines and consensus documents, in order to establish a common criterion in the nutritional treatment of patients with IBD. The objective of this review was to summarise the data published regarding diet in IBD and review the recommendations given by scientific societies.

Prebiotics, Probiotics, Synbiotics, Paraprobiotics and Postbiotic Compounds in IBD.

The increasing incidence of inflammatory bowel diseases (IBD) and the increasing severity of the course of these diseases create the need for developing new methods of therapy. The gut microbiome is extensively studied as a factor influencing the development and course of IBD. The composition of intestinal microbiota can be relatively easily modified by diet (i.e., prebiotics, mainly dietary fibers) and bacterial supplementation using beneficial bacteria strains called probiotics. Additionally, the effects of the improved microbiome could be enhanced or gained by using paraprobiotics (non-viable, inactivated bacteria or their components) and/or postbiotics (products of bacterial metabolism or equal synthetic products that beneficially modulate immunological response and inflammation). This study summarizes the recent works on prebiotics, probiotics, synbiotics (products merging pre- and probiotics), paraprobiotics and postbiotics in IBD.

Ferroptosis: A Double-Edged Sword in Gastrointestinal Disease.

Ferroptosis is a novel form of regulated cell death (RCD) that is typically accompanied by iron accumulation and lipid peroxidation. In contrast to apoptosis, autophagy, and necroptosis, ferroptosis has unique biological processes and pathophysiological characteristics. Since it was first proposed in 2012, ferroptosis has attracted attention worldwide. Ferroptosis is involved in the progression of multiple diseases and could be a novel therapeutic target in the future. Recently, tremendous progress has been made regarding ferroptosis and gastrointestinal diseases, including intestinal ischemia/reperfusion (I/R) injury, inflammatory bowel disease (IBD), gastric cancer (GC), and colorectal cancer (CRC). In this review, we summarize the recent progress on ferroptosis and its interaction with gastrointestinal diseases. Understanding the role of ferroptosis in gastrointestinal disease pathogenesis could provide novel therapeutic targets for clinical treatment.

Probiotic-Induced Tolerogenic Dendritic Cells: A Novel Therapy for Inflammatory Bowel Disease?

Inflammatory bowel diseases (IBDs) are immune-mediated, chronic relapsing diseases with a rising prevalence worldwide in both adult and pediatric populations. Treatment options for immune-mediated diseases, including IBDs, are traditional steroids, immunomodulators, and biologics, none of which are capable of inducing long-lasting remission in all patients. Dendritic cells (DCs) play a fundamental role in inducing tolerance and regulating T cells and their tolerogenic functions. Hence, modulation of intestinal mucosal immunity by DCs could provide a novel, additional tool for the treatment of IBD. Recent evidence indicates that probiotic bacteria might impact immunomodulation both in vitro and in vivo by regulating DCs' maturation and producing tolerogenic DCs (tolDCs) which, in turn, might dampen inflammation. In this review, we will discuss this evidence and the mechanisms of action of probiotics and their metabolites in inducing tolDCs in IBDs and some conditions associated with them.

Nutrición y enfermedad inflamatoria intestinal: posibles mecanismos en la incidencia y manejo / Nutrition and inflammatory bowel disease: possible mechanisms of diet on the incidence and management

La enfermedad inflamatoria intestinal (EII), cuyos fenotipos más frecuentes son la enfermedad de Crohn (EC) y la colitis ulcerosa (CU), tiene una etiología multifactorial, que resulta de la interacción de factores genéticos, ambientales y del microbioma. Su incidencia ha aumentado en las últimas décadas, así como también lo ha hecho la occidentalización de la dieta: alta en grasas, carbohidratos refinados, azúcar, carnes rojas y alimentos procesados. Una dieta occidental es considerada como factor de riesgo para el desarrollo de EII, ya que está asociada a disbiosis, alteración de la barrera intestinal y de la inmunidad del huésped. Existen diversas dietas de eliminación que podrían ejercer un rol en la inducción/mantención de la remisión. Sin embargo, la mayoría requiere estudios de mejor calidad científica para poder recomendarlas. A su vez, existen suplementos nutricionales que estarían asociados a la incidencia y curso de la enfermedad. El objetivo de esta revisión es mostrar el posible rol de la dieta en la incidencia de la EII, y las estrategias dieto-terapéuticas, incluyendo suplementos específicos y nutrición enteral, considerando periodos de crisis y remisión.

Inflammatory bowel diseases (IBD), most frequent phenotypes Crohn's disease and Ulcerative colitis, have a multifactorial etiology, resulting from genetics, environmental triggers and microbiome alterations. Its incidence has been increasing as well as the western diet, high in fat, refined carbohydrates, sugar, red meat and processed foods. A western diet is considered a risk factor for the development of IBD, since it is associated with dysbiosis, alteration of the intestinal barrier and host immunity. There are several elimination diets that could play a role in induction/maintenance of remission. However, most of them require better quality scientific studies. Also, there are nutritional supplements associated with the incidence and evolution of the disease. The aim of this review is to show the possible role of the diet in the incidence, and diet-therapeutic strategies, including specific supplements and enteral nutrition, considering periods of active disease and remission

Nutritional Aspects of Pediatric Gastrointestinal Diseases.

In the last decade, the role of nutritional management in pediatric gastrointestinal diseases has gained increasing popularity. Disease-specific diets have been introduced as conventional treatments by international guidelines. Patients tend to more willingly accept food-based therapies than drugs because of their relatively "harmless" nature. Apart from a diet's therapeutic role, nutritional support is crucial in maintaining growth and improving clinical outcomes in pediatric patients. Despite the absence of classical "side effects", however, it should be emphasized that any dietary modification might have negative consequences on children's growth and development. Hence, expert supervision is always advised, in order to support adequate nutritional requirements. Unfortunately, the media provide an inaccurate perception of the role of diet for gastrointestinal diseases, leading to misconceptions by patients or their caregivers that tends to overestimate the beneficial role of diets and underestimate the potential adverse effects. Moreover, not only patients, but also healthcare professionals, have a number of misconceptions about the nutritional benefits of diet modification on gastrointestinal diseases. The aim of this review is to highlight the role of diet in pediatric gastrointestinal diseases, to detect misconceptions and to give a practical guide for physicians on the basis of current scientific evidence.

Nutrient, Fibre, and FODMAP Intakes and Food-related Quality of Life in Patients with Inflammatory Bowel Disease, and Their Relationship with Gastrointestinal Symptoms of Differing Aetiologies.

BACKGROUND AND AIMS: Certain foods are reported as gut symptom triggers in inflammatory bowel disease [IBD], and fructans are shown to worsen non-inflammatory symptoms in inactive IBD, which may result in self-imposed dietary restrictions. The aim of this study was to investigate nutrient and FODMAP intakes, and the relationship between gut symptoms and dietary intake, in IBD. METHODS: Nutrient, fibre, and FODMAP intakes were estimated using 7-day food records in patients with active IBD [Active IBD], inactive IBD with non-inflammatory gut symptoms [Inactive IBD-GI], inactive IBD without gut symptoms [Inactive IBD], and healthy controls. Nutrient intakes, numbers of participants achieving national recommendations, and food-related quality of life [FR-QoL] were compared across study groups. RESULTS: Food diaries were obtained from 232 patients with IBD [65 Active IBD, 86 Inactive IBD-GI, 81 Inactive IBD] and 84 healthy controls. Patients with Active IBD had significantly lower intakes of numerous micronutrients, including iron, folate, and vitamin C, compared with controls. All IBD groups consumed less total fibre [4.5 to 5.8 g/day] than controls [p = 0.001], and total FODMAP and fructan intakes were lower in Active IBD compared with controls. Strikingly, FR-QoL was significantly lower in all IBD groups compared with controls [all p = 0.001]. CONCLUSIONS: This study revealed lower intakes of fibre, FODMAPs, and micronutrients, in addition to poorer FR-QoL, in Active IBD and Inactive IBD-GI with gut symptoms compared with healthy controls. Future research should address dietary restrictions responsible for these differences.

Perioperative nutritional optimization in inflammatory bowel diseases: when and how?

Inflammatory bowel diseases (IBDs), including ulcerative colitis (UC) and Crohn's disease (CD), are commonly associated with important changes in nutritional status (NS). Both malnutrition and obesity have a negative impact on the course of both diseases, with greater risks of postoperative complications, such as anastomotic dehiscences, reoperations, prolonged hospitalizations, and increased mortality. The diagnostic criteria for identifying individuals at nutritional risk, with clear indication for preoperative nutritional therapy, involves several factors. Oral nutrition should be the first choice of nutritional support. If the patient has difficulty in consuming food, the enteral route is the second option, through elementary (amino acids), semi-elementary (oligopeptides), or polymeric (whole proteins) formulas. When oral or enteral routes are not indicated (in the presence of intestinal obstruction or ischemia, fistula, or bleeding), total parenteral nutrition can meet the daily nutritional needs of the critically ill patient. Nutritional support can be performed exclusively or in an associated way, which will depend on the nutritional severity of the patient with IBD. Nutritional screening should be performed at all stages of the disease, always individually and with professionals with experience in IBD. The reduction of complications in the perioperative period is not only associated with adequate surgical technique, but also with adequate nutritional support and clinical preparation before surgery. Therefore, the dietitian with a focus in IBD has an important role in the multidisciplinary team, collaborating with all stages of treatment and with the optimization of the nutritional status of the surgical patient. (AU)

Advances in Technologies for Highly Active Omega-3 Fatty Acids from Krill Oil: Clinical Applications.

Euphausia superba, commonly known as krill, is a small marine crustacean from the Antarctic Ocean that plays an important role in the marine ecosystem, serving as feed for most fish. It is a known source of highly bioavailable omega-3 polyunsaturated fatty acids (eicosapentaenoic acid and docosahexaenoic acid). In preclinical studies, krill oil showed metabolic, anti-inflammatory, neuroprotective and chemo preventive effects, while in clinical trials it showed significant metabolic, vascular and ergogenic actions. Solvent extraction is the most conventional method to obtain krill oil. However, different solvents must be used to extract all lipids from krill because of the diversity of the polarities of the lipid compounds in the biomass. This review aims to provide an overview of the chemical composition, bioavailability and bioaccessibility of krill oil, as well as the mechanisms of action, classic and non-conventional extraction techniques, health benefits and current applications of this marine crustacean.

Intermittent administration of a fasting-mimicking diet reduces intestinal inflammation and promotes repair to ameliorate inflammatory bowel disease in mice.

Recent studies have revealed that calorie restriction is able to modulate immune system and aid in intervention of immune disorders. Inflammatory bowel disease (IBD) is an immune disease in the intestine caused by interplay between genetic susceptibility and environmental factors such as diets. Here we analyzed the therapeutic effect of intermittent calorie restriction with a fasting-mimicking diet (FMD) on dextran sodium sulfate (DSS)-induced chronic IBD model in mice. Two cycles of FMD was administered after IBD symptoms occurred in the mice. FMD administration significantly reduced the score of disease activity index. FMD reversed DSS-mediated shortening of colon length, infiltration of lymphocytes in the crypt of colon, and accumulation of CD4+ cells in the colon and small intestine. The expression of an inflammation marker NLRP3 was also reduced by FMD administration. The percentage of CD4+ T cells in both peripheral blood and spleen was also reduced by FMD. In addition, FMD application reversed DSS-mediated reduction in intestinal stem cell marker Lgr5, while the cell proliferation markers Ki67 and PCNA were increased by FMD. Taken together, these results indicate that in the mouse model of IBD, application of the FMD can effectively ameliorate the symptoms and pathogenesis of IBD through reducing the inflammation of intestine and promoting the regeneration and repair of the damaged intestinal epithelium.

Dietary intake patterns among adults with inflammatory bowel disease in the United States, 2015.

BACKGROUND: Dietary behavior and nutrient intake patterns among U.S. men and women with inflammatory bowel disease (IBD) are unclear at the population level. METHODS: This cross-sectional study compared dietary intake patterns among U.S. adults (aged ≥18 years) with and without IBD in the 2015 National Health Interview Survey (N = 33,626). Age-standardized weighted prevalences for intake of fruits, vegetables, dairy, whole grain bread, dietary fiber, calcium, total added sugars, sugar-sweetened beverages (SSBs), processed meat, and supplement use were compared between adults with and without IBD by sex. RESULTS: In 2015, an estimated 3 million adults (1.3%) reported IBD. Compared with adults without IBD, adults with IBD were more likely to be older, non-Hispanic white, not currently working, former smokers, and former alcohol drinkers. Overall, dietary behaviors were similar among adults with and without IBD. However, adults with IBD were more likely to take vitamin D supplements (31.5% vs 18.8%) and consume dietary fiber <16.7 grams(g)/day, the amount that 50% of U.S. adults consumed (51.8% vs 44.1%), than those without IBD. Compared with their counterparts, men with IBD were more likely to consume vegetables ≥1 time/day (84.9% vs 76.0%) and take any supplement (59.6% vs 46.0%); women with IBD were more likely to have SSBs ≥2 times/day (26.8% vs 17.8%) and total added sugars ≥14.6 teaspoons(tsp)/day, the amount that 50% of U.S. adults consumed (55.3% vs 46.7%). CONCLUSIONS: Adopting a healthy diet, especially limiting added sugars intake among women with IBD, might be important for the overall health.

Inflammatory Bowel Diseases: Is There a Role for Nutritional Suggestions?

Nutrition has an important impact on inflammatory bowel diseases (IBD). In particular, several studies have addressed its role in their pathogenesis, showing how the incidence of IBD significantly increased in recent years. Meanwhile, nutrition should be considered a component of the treatment of the disease, both as a therapy itself, and especially in the perspective of correcting the various nutritional deficiencies shown by these patients. In this perspective, nutritional suggestions are very important even in the most severe forms of IBD, requiring hospitalization or surgical treatment. Although current knowledge about nutrition in IBD is increasing over time, nutritional suggestions are often underestimated by clinicians. This narrative review is an update summary of current knowledge on nutritional suggestions in IBD, in order to address the impact of nutrition on pathogenesis, micro- and macro-nutrients deficiencies (especially in the case of sarcopenia and obesity), as well as in hospitalized patients.