Dietary Strategies for Maintenance of Clinical Remission in Inflammatory Bowel Diseases: Are We There Yet?

A Comprehensive Review of Dietary Approaches in Maintaining Remission of Inflammatory Bowel Diseases in Adults

Inflammatory bowel disease (IBD) poses significant challenges in its management, encompassing a spectrum of conditions from Crohn's disease to ulcerative colitis. Dietary interventions have emerged as integral components of the multidisciplinary approach to IBD management, with implications ranging from disease prevention to treatment of active manifestations and addressing complications such as malnutrition. While dietary interventions show promise in improving outcomes for some patients with IBD, there is no consensus in the existing literature regarding remission maintenance in those patients. Furthermore, many patients explore dietary modifications often guided by anecdotal evidence or personal experiences and this could lead to malnutrition and decreased quality of life. This comprehensive review synthesizes existing literature to elucidate the complex interplay between diet and IBD, offering insights into the efficacy and safety of various dietary modalities in maintaining disease remission. It also highlights the importance of patient education in navigating dietary choices and potential risks associated with food avoidance, including the heightened risk of micronutrient deficiencies. Furthermore, it emphasizes the pivotal role of a multidisciplinary care team comprising clinicians and dietitians in providing personalized dietary guidance tailored to individual patient needs and goals. By synthesizing the latest evidence and providing insights into both the potential benefits and risks of dietary interventions, this review could be used as a resource for healthcare professionals and patients alike in navigating the complex landscape of dietary management in IBD.

Effectiveness of a novel diet in attenuation of clinical activity of disease in patients with ulcerative colitis: a randomized, clinical trial

Dietary intake plays a pivotal role in ulcerative colitis (UC) initiation and prognosis. The aim of this study was to investigate the effect of a combined Mediterranean, low-FODMAP diet accompanied with partial enteral nutrition (PEN) on clinical and para-clinical characteristics of patients with UC. Fifty patients with active mild to moderate UC were received either a combined diet or a regular diet for 6 weeks. Before and after the intervention, disease activity index, quality of life and some inflammatory and oxidative stress factors were measured using valid and reliable questionnaires and blood sampling. Disease activity index was significantly decreased in the combined diet group in comparison to control diet group (p = 0.043), and baseline data (p < 0.001). Moreover, the quality of life score increased significantly in the combined diet group compared to the control group, and the baseline data (p < 0.001). Serum level of high sensitive C-reactive protein (hs-CRP) decreased significantly in the combined group (p < 0.01), while it increased in the control group non-significantly. Serum total anti-oxidant capacity (TAC) changes were not statistically significant in two groups. This study indicates that this combination diet has the potential to be used as a safe and highly effective approach in patients with significant intestinal symptoms. Further clinical trial studies with different duration of intervention are needed to confirm these results.Trial registration: The study was registered on IRCT.ir with registration number of IRCT20100524004010N38, on 25/04/2023.

Dose-dependent effects of enteral nutrition on the faecal microbiota and short chain fatty acids

INTRODUCTION

Enteral nutrition (EN) involves replacing all or part of a person's habitual diet with a nutritional formula. The impact of varying doses of EN on the gut microbiome remains understudied.

METHODS

Healthy adults replaced all (100% EN) or part (85% EN, 50% EN and 20% EN) of their energy requirements with EN for 7 days. Faecal samples were collected before and on day 7 of interventions. Faecal pH, short chain fatty acids (SCFAs), branched-chain fatty acids (BCFAs) and 16S rRNA sequencing were performed. Dietary assessment was performed with 7-day food diaries.

RESULTS

Sixty-one participants (31 females; median (IQR) age: 24.7 (23.0-27.8) years) were recruited. A dose-dependent impact of EN on faecal microbiota, SCFAs, BCFAs) and pH was observed, with changes detectable at EN intakes of at least 50% of energy requirements. 100% and 85% EN reduced the abundance of fibre-fermenting taxa such as Agathobacter, Faecalibaterium, Succinivibrio and Acidaminococcus. In parallel, potentially harmful organisms like Eubacterium, Actinomyces, and Klebsiella increased. In the 50% EN group, adherence to a diet high in fish, vegetables, potatoes, non-alcoholic beverages, and fat spreads, and low in cereal products, milk, and meat negatively correlated with changes in microbiota structure (r = -0.75, P = 0.025). This signal was not observed when using compositional tools for microbiota analysis.

CONCLUSIONS

EN detrimentally influences the faecal microbiota and diet-related bacterial metabolites in a dose-dependent manner, particularly at doses of at least 50%. The findings of this study have implications for the dietary management and counselling of patients receiving high volume EN.

Role of diet in prevention versus treatment of Crohn's disease and ulcerative colitis

Diet is a modifiable risk factor for disease course and data over the past decade have emerged to indicate its role in Crohn's disease (CD) and ulcerative colitis (UC). However, literature is riddled with misinterpretation of data, often leading to unexpected or conflicting results. The key understanding is that causative factors in disease development do not always proceed to an opportunity to change disease course, once established. Here, we discuss the data on dietary influences in three distinct disease states for CD and UC-predisease, active disease and quiescent disease. We appraise the literature for how our dietary recommendations should be shaped to prevent disease development and if or how that differs for CD and UC induction therapy and maintenance therapy. In UC, principles of healthy eating are likely to play a role in all states of disease. Conversely, data linking dietary factors to CD prevention and treatment are paradoxical with the highest quality evidence for CD treatment being exclusive enteral nutrition, a lactose, gluten and fibre-free diet comprising solely of ultraprocessed food-all dietary factors that are not associated or inversely associated with CD prevention. High-quality evidence from dietary trials is much awaited to expand our understanding and ultimately lead our dietary recommendations for targeted patient populations.

Inflammatory bowel disease: recent developments

Paediatric-onset inflammatory bowel disease (IBD) is a complex and heterogenous condition. Incidence of disease in those aged <18 years has doubled over the last 25 years, with concurrent increased prevalence and no decrease in disease severity. The tools available at diagnosis for investigation have developed over the last 10 years, including better utilisation of faecal calprotectin, improved small bowel imaging and video capsule endoscopy. Alongside this, management options have increased and include biological and small molecule therapies targeting alternative pathways (such as interleukin 12/23, integrins and Janus kinase/signal transducers and activators of transcription, JAK-STAT pathways) and better understanding of therapeutic drug monitoring for more established agents, such as infliximab. Dietary manipulation remains an interesting but contentious topic.This review summarises some of the recent developments in the diagnosis, investigation and management of IBD in children and young people. IBD is increasingly recognised as a continuum of disease, with a proportion of patients presenting with classical Crohn's disease or ulcerative colitis phenotypes. Future implementation of personalisation and stratification strategies, including clinical and molecular biomarkers, implementation of predictors of response and outcome and use of additional therapies, will continue to require working within clinical networks and multiprofessional teams.

Dietary Perceptions among Patients with Crohn's Disease in Clinical Remission: Comparison with an Era Preceding the Availability of Biologic Therapy

Introduction

Dietary temperance significantly affects the quality of life of patients with Crohn's disease (CD) and remains a major concern. However, perceptions of diet in remission may have changed from the era when treatment options were limited. Therefore, we compared the dietary perceptions and treatment of patients with CD in remission with previously published data from the time biologic therapy was not introduced.

Methods

We compared the data of 254 patients with CD in remission who completed a questionnaire survey in 2022 with those of 76 patients with CD in remission collected in 2003, when biologics were not used for maintenance therapy in Japan. Remission was defined as a CD activity index of 150 or less in both studies. Perceptions of diet (degree of eating whatever one likes) were assessed using single-item nominal scale responses.

Results

The percentage of patients receiving enteral nutrition therapy had decreased (past vs. present: 43.4 vs. 12.6%), while the proportion of patients receiving biologic therapy increased (0 vs. 88.6%, respectively). The percentages of patients who responded "not at all," "sometimes," and "mostly" when asked if they could eat whatever they liked had changed, respectively, from 9.2%, 46.1%, and 44.7% in the past to 4.3%, 25.2%, and 70.5% in the present.

Conclusion

The proportion of those who ate whatever they liked and the mean body mass index increased in comparison with the corresponding values 20 years ago. With the advent of biologic therapies, the number of patients with CD who can enjoy eating has increased.

Perceptions Toward Established and Novel Dietary Therapies for Crohn's Disease Management Among Adult Patients: Results From a Questionnaire Survey

Background

Exclusive enteral nutrition (EEN) and partial enteral nutrition (PEN) remain the only established dietary therapies in Crohn's disease (CD) management. We conducted a questionnaire survey to evaluate the perceptions of adults with CD toward established and emerging food-based dietary therapies.

Methods

A 26-question anonymous survey was mailed to 300 adults receiving biologic treatment. Two researchers independently conducted a thematic analysis of open-ended responses. Machine learning with the Random Forest-Recursive Feature Elimination algorithm identified predictors of willingness to try dietary therapies.

Results

One hundred and sixty patients (53% female) completed and returned the survey. Forty-two percent were following some form of exclusion diet, with low-spice and low-fiber diets being the most popular. Although only a quarter of patients believed that EEN/PEN could help with their CD, more than half believed that diet could help, with another 13% already using diet for CD management. While half of the patients were willing to try EEN, the majority were willing to try PEN instead (51% vs. 79%; P < .001). Forty-two percent of patients preferred food-based dietary plans prepared at home over EEN/PEN options. The most important predictors for willingness to try dietary therapies were age (25-65 years), recent symptoms, previous exposure to EEN/PEN, and current exclusion diet use. The top concerns about PEN were taste/palatability, satiety/hunger, and taste fatigue.

Conclusions

Most adults preferred to follow a food-based dietary therapy over EEN/PEN. The majority would try PEN though which allows for more flexibility to incorporate in habitual diet and may be easier to comply with than the EEN.

Evidence and hypotheses on adverse effects of the food additives carrageenan (E 407)/processed Eucheuma seaweed (E 407a) and carboxymethylcellulose (E 466) on the intestines: a scoping review

This scoping review provides an overview of publications reporting adverse effects on the intestines of the food additives carrageenan (CGN) (E 407)/processed Eucheuma seaweed (PES) (E 407a) and carboxymethylcellulose (CMC) (E 466). It includes evidence from human, experimental mammal and in vitro research publications, and other evidence. The databases Medline, Embase, Scopus, Web of Science Core Collection, Cochrane Database of Systematic Reviews and Epistemonikos were searched without time limits, in addition to grey literature. The publications retrieved were screened against predefined criteria. From two literature searches, 2572 records were screened, of which 224 records were included, as well as 38 records from grey literature, making a total of 262 included publications, 196 on CGN and 101 on CMC. These publications were coded and analyzed in Eppi-Reviewer and data gaps presented in interactive maps. For CGN, five, 69 and 33 research publications on humans, experimental mammals and in vitro experiments were found, further separated as degraded or native (non-degraded) CGN. For CMC, three human, 20 animal and 14 in vitro research publications were obtained. The most studied adverse effects on the intestines were for both additives inflammation, the gut microbiome, including fermentation, intestinal permeability, and cancer and metabolic effects, and immune effects for CGN. Further studies should focus on native CGN, in the form and molecular weight used as food additive. For both additives, randomized controlled trials of sufficient power and with realistic dietary exposure levels of single additives, performed in persons of all ages, including potentially vulnerable groups, are needed.

Plant-based Diets for Inflammatory Bowel Disease: What Is the Evidence?

BACKGROUND

Inflammatory bowel disease is a chronic incurable condition that carries a high morbidity burden for patients. Plant-based diets have emerged as a potentially safe and effective treatment strategy for this condition. However, no attempt has been made to summarize the literature in this field. In this review, we aim to define variants of plant-based diets that have been studied, evaluate their findings, and identify knowledge gaps that warrant further investigation.

METHODS

A literature search was conducted on MEDLINE and Embase.

RESULTS

Twenty-three studies with 2304 participants were included in this review. Eleven studies (48%) were case reports and 8 (35%) were single-arm trials. Semivegetarian diets were the most commonly studied plant-based diet (n = 14, 61%). Most studies reported that plant-based diets were safe and effective in managing inflammatory bowel disease. However, significant limitations restrict the quality and interpretability of these findings, including a paucity of controlled data, small sample sizes, and inconsistent reporting of dietary adherence.

CONCLUSIONS

Although initial findings appear promising, it remains unclear whether plant-based diets are an effective adjunct or sole therapy for managing inflammatory bowel disease. Future investigators should aim to conduct methodologically rigorous interventional trials with appropriate control data and consistent and meaningful outcome reporting.

Pharmacological Therapy in Inflammatory Bowel Diseases: A Narrative Review of the Past 90 Years

Inflammatory Bowel Diseases had their first peak in incidence in countries in North America, Europe, and Oceania and are currently experiencing a new acceleration in incidence, especially in Latin America and Asia. Despite technological advances, 90 years after the development of the first molecule for the treatment of IBD, we still do not have drugs that promote disease remission in a generalized way. We carried out a narrative review on therapeutic advances in the treatment of IBD, the mechanisms of action, and the challenges facing the therapeutic goals in the treatment of IBD. Salicylates are still used in the treatment of Ulcerative Colitis. Corticosteroids have an indication restricted to the period of therapeutic induction due to frequent adverse events, while technologies with less systemic action have been developed. Most immunomodulators showed a late onset of action, requiring a differentiated initial strategy to control the disease. New therapeutic perspectives emerged with biological therapy, initially with anti-TNF, followed by anti-integrins and anti-interleukins. Despite the different mechanisms of action, there are similarities between the general rates of effectiveness. These similar results were also evidenced in JAK inhibitors and S1p modulators, the last therapeutic classes approved for the treatment of IBD.

ESPEN guideline on Clinical Nutrition in inflammatory bowel disease

The present guideline is an update and extension of the ESPEN scientific guideline on Clinical Nutrition in Inflammatory Bowel Disease published first in 2017. The guideline has been rearranged according to the ESPEN practical guideline on Clinical Nutrition in Inflammatory Bowel Disease published in 2020. All recommendations have been checked and, if needed, revised based on new literature, before they underwent the ESPEN consensus procedure. Moreover, a new chapter on microbiota modulation as a new option in IBD treatment has been added. The number of recommendations has been increased to 71 recommendations in the guideline update. The guideline is aimed at professionals working in clinical practice, either in hospitals or in outpatient medicine, and treating patients with IBD. General aspects of care in patients with IBD, and specific aspects during active disease and in remission are addressed. All recommendations are equipped with evidence grades, consensus rates, short commentaries and links to cited literature.

Improvement of ulcerative colitis control by searching and restricting of inflammatory trigger factors in daily clinical practice

BACKGROUND/AIMS

Exacerbating factors of ulcerative colitis (UC) are multiple and complex with individual influence. We aimed to evaluate the efficacy of disease control by searching and restricting inflammation trigger factors of UC relapse individually in daily clinical practice.

METHODS

Both patients with UC history or new diagnosis were asked to avoid dairy products at first doctor visit. Individual-reported potential trigger factors were restricted when UC flared up (Mayo endoscopy score ≥1) from remission status. The remission rate, duration to remission and medication were analyzed between the groups of factor restriction complete, incomplete and unknown.

RESULTS

The total remission rate was 91.7% of 108 patients with complete restriction of dairy product. The duration to remission of UC history group was significantly longer than that of new diagnosis group (88.5 days vs. 43.4 days, P=0.006) in patients with initial endoscopic score 2-3, but no difference in patients with score 1. After first remission, the inflammation trigger factors in 161 relapse episodes of 72 patients were multiple and personal. Milk/dairy products, herb medicine/Chinese tonic food and dietary supplement were the common factors, followed by psychological issues, non-dietary factors (smoking cessation, cosmetic products) and discontinuation of medication by patients themselves. Factor unknown accounted for 14.1% of patients. The benefits of factor complete restriction included shorter duration to remission (P<0.001), less steroid and biological agent use (P=0.022) when compared to incomplete restriction or factor unknown group.

CONCLUSIONS

Restriction of dairy diet first then searching and restricting trigger factors personally if UC relapse can improve the disease control and downgrade the medication usage of UC patients in daily clinical practice.

Therapy Strategies for Children Suffering from Inflammatory Bowel Disease (IBD)—A Narrative Review

The incidence of inflammatory bowel disease (IBD) is increasing, and more children at a younger age are affected. The pathogenesis seems to be an interaction of microbial factors, a sensitivity of the immune system, and the intestinal barrier, leading to an inappropriate immune response. Not only has the role of biological agents become more important in the last decade in the treatment of children and adolescents, but also new insights into the composition of the gastrointestinal microbiome and personal diet implications have increased our understanding of the disease and opened up potential therapeutic pathways. This narrative review provides an overview of current recommendations, therapeutic options, drug monitoring, and practical guidelines for paediatricians involved with paediatric IBD patients. Furthermore, the off-label use of potential helpful drugs in the treatment of these patients is discussed.

Exclusive enteral nutrition: An optimal care pathway for use in children with active luminal Crohn's disease

AIM

Exclusive enteral nutrition (EEN) is recommended as a first-line therapy for active luminal paediatric Crohn's disease, by many contemporary consensus guidelines. However, EEN protocols vary internationally. A key enabler for the use of EEN therapy has been identified as the standardisation of protocols. The aim of this study was to develop an optimal care pathway for use of EEN in children with active luminal Crohn's disease.

METHODS

A working group of 11 paediatric gastroenterology dietitians and one paediatric gastroenterologist from Australia and New Zealand was convened to develop a standard optimal care pathway. Seven key areas were identified; clinical indications, workup assessments, EEN prescription, monitoring, food reintroduction, partial enteral nutrition and maintenance enteral nutrition. Recent literature was reviewed, assessed according to the National Health and Medical Research Council guidelines, and consensus statements were developed and voted on. Consensus opinion was used where literature gaps existed.

RESULTS

A total of nineteen consensus statements from the seven key areas were agreed upon. The consensus statements informed the optimal care pathway for children with active luminal undertaking EEN in Australia and New Zealand.

CONCLUSION

This study developed an EEN optimal care pathway to facilitate standardisation of clinical care for children with active luminal Crohn's disease, and hopefully improve clinical outcomes and identify areas for future research.

Feeding Difficulties Associated with IBD during the Working Day: Qualitative Study, Alicante Spain

Inflammatory bowel disease (IBD) is a chronic disease characterized by inflammation of the gastrointestinal tract. Nutrition is a key aspect as it can modulate much of the symptomatology. People affected by IBD often experience difficulties at work in all areas, including adapting their dietary management to workplace situations. The aim of this study is to identify the difficulties associated with eating during the working day in people diagnosed with IBD. A qualitative study was conducted through a nominal and focus group with people affected by IBD. After the thematic analysis of the data, three main themes emerged: management of food during the working day, searching for strategies to live with the disease, and the importance of visibility and support. This study shows that IBD influences the working life of people with IBD and makes it difficult to maintain an adequate diet. The institutions in charge of the treatment of IBD patients should consider the support of multidisciplinary teams, including nutrition professionals, as a fundamental part of the pathology control and dietary treatment to minimize its repercussions at work.

Dietary triggers of gut inflammation following exclusive enteral nutrition in children with Crohn's disease: a pilot study

Background

The anti-inflammatory effect of exclusive enteral nutrition on the gut of children with Crohn’s disease is rapidly lost after food reintroduction. This study assessed disease dietary triggers following successful treatment with exclusive enteral nutrition.

Methods

Nutrient intake, dietary patterns and dietary biomarkers in faeces (gluten immunogenic peptides, undigestible starch, short chain fatty acids) were assessed in 14 children with Crohn’s disease during early food reintroduction, following exclusive enteral nutrition. Groups above (Group A) and below (Group B) the median levels of faecal calprotectin after food reintroduction were assigned for comparative analysis.

Results

Intakes of fibre, gluten-containing cereals and red and processed meat were significantly higher in Group A than Group B; (median [Q1, Q3], g/day; Fibre: 12.1 [11.2, 19.9] vs. 9.9 [7.6, 12.1], p = 0.03; Red and processed meat: 151 [66.7, 190] vs. 63.3 [21.7, 67], p = 0.02; gluten-containing cereals: 289 [207, 402] vs. 203 [61, 232], p = 0.035). A diet consisting of cereals and meat products was predictive (92% accuracy) of higher faecal calprotectin levels after food reintroduction. In faeces, butyrate levels, expressed as absolute concentration and relative abundance, were higher in Group A than Group B by 28.4 µmol/g (p = 0.015) and 6.4% (p = 0.008), respectively. Levels of gluten immunogenic peptide and starch in faeces did not differ between the two groups.

Conclusions

This pilot study identified potential dietary triggers of gut inflammation in children with Crohn’s disease after food reintroduction following treatment with exclusive enteral nutrition.

Trial registration: Clinical trials.gov registration number: NCT02341248; Clinical trials.gov URL: https://clinicaltrials.gov/ct2/show/NCT02341248 (retrospectively registered).

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-021-02029-4.

The dietary fibre rhamnogalacturonan improves intestinal epithelial barrier function in a microbiota-independent manner

BACKGROUND AND PURPOSE

Dietary fibre comprises a complex group of polysaccharides that are indigestible but are fermented by gut microbiota, promoting beneficial effects to the intestinal mucosa indirectly through the production of short chain fatty acids. We found that a polysaccharide, rhamnogalacturonan (RGal), from the plant Acmella oleracea, has direct effects on intestinal epithelial barrier function. Our objective was to determine the mechanism whereby RGal enhances epithelial barrier function.

EXPERIMENTAL APPROACH

Monolayers of colonic epithelial cell lines (Caco-2, T84) and of human primary cells from organoids were mounted in Ussing chambers to assess barrier function. The cellular mechanism of RGal effects on barrier function was determined using inhibitors of TLR-4 and PKC isoforms.

KEY RESULTS

Apically applied RGal (1000 μg/ml) significantly enhanced barrier function as shown by increased transepithelial electrical resistance (TER) and reduced fluorescein isothiocyanate (FITC)-dextran flux in Caco-2, T84 and human primary cell monolayers, and accelerated tight junction reassembly in Caco-2 cells in a calcium switch assay. RGal also reversed the barrier-damaging effects of inflammatory cytokines on FITC-dextran flux and preserved the tight junction distribution of occludin. RGal activated TLR4 in TLR4-expressing HEK reporter cells, an effect that was significantly inhibited by the TLR4 inhibitor, C34. The effect of RGal was also dependent on PKC, specifically the isoforms PKCd and PKCζ.

CONCLUSION AND IMPLICATIONS

RGal enhances intestinal epithelial barrier function through activation of TLR4 and PKC signaling pathways. Elucidation of RGal mechanisms of action could lead to new, dietary approaches to enhance mucosal healing in inflammatory bowel diseases.

Dietary Management in Pediatric Patients with Crohn's Disease

It has been widely endorsed that a multifactorial etiology, including interaction between genetic and environmental factors, can contribute to Crohn's Disease (CD) pathogenesis. More specifically, diet has proven to be able to shape gut microbiota composition and thus is suspected to play a significant role in inflammatory bowel disease (IBD) pathogenesis. Moreover, poor nutritional status and growth retardation, arising from several factors such as reduced dietary intake or nutrient leakage from the gastrointestinal tract, represent the hallmarks of pediatric CD. For these reasons, multiple research lines have recently focused on the utilization of dietary therapies for the management of CD, aiming to target concurrently mucosal inflammation, intestinal dysbiosis and optimization of nutritional status. The forerunner of such interventions is represented by exclusive enteral nutrition (EEN), a robustly supported nutritional therapy; however, it is burdened by monotony and low tolerance in the long term. Novel dietary interventions, such as Crohn's Disease Exclusion Diet or Crohn's Disease treatment with eating, have shown their efficacy in the induction of remission in pediatric patients with CD. The aim of the present narrative review is to provide a synopsis of the available nutritional strategies in the management of pediatric CD and to discuss their application in the dietary management of these patients.

Exclusive enteral nutrition in children and adolescents with Crohn disease: Dietitian perspectives and practice

AIM

In newly diagnosed paediatric Crohn disease, exclusive enteral nutrition (EEN) is recommended as a first-line treatment for remission induction. However, EEN protocols vary internationally. The development of best practice protocols may make it easier to make definitive conclusions about optimal EEN therapy, and may improve patient outcomes. This study aims to determine the variations in current dietitian EEN practice within Australia and New Zealand (NZ) to inform a common EEN protocol in the future, and to gather perspectives on the need for nutrition resources for patients with inflammatory bowel disease (IBD).

METHODS

A questionnaire was created and emailed to paediatric dietitians working with gastroenterologists in public and private paediatric centres in Australia and NZ. Respondents were invited to provide details of their perspectives of EEN therapy and protocol details.

RESULTS

Eighteen paediatric dietitians responded to the questionnaire, 10 from Australia and 8 from NZ. There was clear consensus between respondents on the duration of EEN being 6 and 8 weeks, the need for close dietitian supervision while on EEN, and the method of food reintroduction. There was lack of consensus between dietitians regarding permitted concomitant foods whilst on EEN. This study also determined a potential benchmarking relationship between IBD dietitian hours and numbers of patients on EEN per year in a centre.

CONCLUSIONS

Paediatric dietitians in Australia and NZ are mostly aligned in their practice of EEN. Development of a standard EEN protocol, and patient IBD resources, will further align practice and allow for greater research possibilities.

Diet and Nutrition in Pediatric Inflammatory Bowel Diseases

Both genetic and environmental factors are involved in the onset of inflammatory bowel disease (IBD). In particular, diet composition is suspected to significantly contribute to IBD risk. In recent years, major interest has raised about the role of nutrition in disease pathogenesis and course, and many studies have shown a clear link between diet composition and intestinal permeability impairment. Moreover, many IBD-related factors, such as poor dietary intake, nutrients loss and drugs interact with nutritional status, thus paving the way for the development of many therapeutic strategies in which nutrition represents the cornerstone, either as first-line therapy or as reversing nutritional deficiencies and malnutrition in IBD patients. Exclusive enteral nutrition (EEN) is the most rigorously supported dietary intervention for the treatment of Crohn's Disease (CD), but is burdened by a low tolerability, especially in pediatric patients. Promising alternative regimens are represented by Crohn's Disease Exclusion Diet (CDED), and other elimination diets, whose use is gradually spreading. The aim of the current paper is to provide a comprehensive and updated overview on the latest evidence about the role of nutrition and diet in pediatric IBD, focusing on the different nutritional interventions available for the management of the disease.

Nutritional Therapy Strategies in Pediatric Crohn's Disease

The increase in incidences of pediatric Crohn's Disease (CD) worldwide has been strongly linked with dietary shifts towards a Westernized diet, ultimately leading to altered gut microbiota and disturbance in intestinal immunity and the metabolome. Multiple clinical studies in children with CD have demonstrated the high efficacy of nutritional therapy with exclusive enteral nutrition (EEN) to induce remission with an excellent safety profile. However, EEN is poorly tolerated, limiting its compliance and clinical application. This has spiked an interest in the development of alternative and better-tolerated nutritional therapy strategies. Several nutritional therapies have now been designed not only to treat the nutritional deficiencies seen in children with active CD but also to correct dysbiosis and reduce intestinal inflammation. In this review, we report the most recent insights regarding nutritional strategies in children with active CD: EEN, partial enteral nutrition (PEN), Crohn's disease exclusive diet (CDED), and CD treatment-with-eating diet (CD-TREAT). We describe their setup, efficacy, safety, and (dis)advantages as well as some of their potential mechanisms of action and perspectives. A better understanding of different nutritional therapeutic options and their mechanisms will yield better and safer management strategies for children with CD and may address the barriers and limitations of current strategies in children.

Diet and Nutrients in Gastrointestinal Chronic Diseases

Diet and nutrition are known to play key roles in many chronic gastrointestinal diseases, regarding both pathogenesis and therapeutic possibilities. A strong correlation between symptomatology, disease activity and eating habits has been observed in many common diseases, both organic and functional, such as inflammatory bowel disease and irritable bowel syndrome. New different dietary approaches have been evaluated in order improve patients’ symptoms, modulating the type of sugars ingested, the daily amount of fats or the kind of metabolites produced in gut. Even if many clinical studies have been conducted to fully understand the impact of nutrition on the progression of disease, more studies are needed to test the most promising approaches for different diseases, in order to define useful guidelines for patients.