Systematic review with meta-analysis: dietary intake in adults with inflammatory bowel disease

Effects of Milk and Dairy on the Risk and Course of Inflammatory Bowel Disease versus Patients' Dietary Beliefs and Practices: A Systematic Review

BACKGROUND

The role of the environment in the pathogenesis of inflammatory bowel disease (IBD) is undisputed, especially in light of numerous epidemiological data showing the increasing prevalence of IBD worldwide. Although no specific environmental factors have been identified, the diet has received the most attention as a potential modifier of the onset and course of IBD and as a therapeutic intervention. The Westernization of the diet is repeatedly cited as a crucial aspect of the change in IBD prevalence, but data on the impact of diet on the course of IBD are still limited and the effectiveness of dietary interventions remains uncertain. Milk remains one of the most discussed dietary agents in IBD.

MATERIALS AND METHODS

We performed a systematic review of the literature published between January 2010 and March 2024 on three databases, Pubmed, Web of Knowledge, and Embase, to assess the impact of milk and dairy products on the risk and course of IBD, as well as patients' dietary beliefs and practices.

RESULTS

We included 37 original studies in our review.

CONCLUSIONS

There is no clear evidence that milk and dairy products influence the incidence and course of IBD. The studies that assess this issue are characterized by great heterogeneity. Milk and dairy are among the most commonly excluded foods by patients with IBD, which may have clinical implications.

Multimodal Prehabilitation for Patients with Crohn's Disease Scheduled for Major Surgery: A Narrative Review

Approximately 15-50% of patients with Crohn's disease (CD) will require surgery within ten years following the diagnosis. The management of modifiable risk factors before surgery is essential to reduce postoperative complications and to promote a better postoperative recovery. Preoperative malnutrition reduced functional capacity, sarcopenia, immunosuppressive medications, anemia, and psychological distress are frequently present in CD patients. Multimodal prehabilitation consists of nutritional, functional, medical, and psychological interventions implemented before surgery, aiming at optimizing preoperative status and improve postoperative recovery. Currently, studies evaluating the effect of multimodal prehabilitation on postoperative outcomes specifically in CD are lacking. Some studies have investigated the effect of a single prehabilitation intervention, of which nutritional optimization is the most investigated. The aim of this narrative review is to present the physiologic rationale supporting multimodal surgical prehabilitation in CD patients waiting for surgery, and to describe its main components to facilitate their adoption in the preoperative standard of care.

The association between dietary patterns and disease severity in patients with ulcerative colitis

Ulcerative colitis (UC) is a chronic inflammatory disease involving the colon and rectum. One of the most modifiable environmental factors affecting UC severity is the patient's dietary pattern. Although the role of dietary patterns on UC aetiology has been investigated previously, its relationship with disease severity has not yet been elucidated. This study examined the association between UC patients' dietary patterns and disease severity. This cross-sectional study was conducted in 340 UC patients. Using an FFQ, food patterns were assessed. Twenty-five food categories were categorised based on the similarity of the nutrient composition of the food using the factor analysis method. A simple clinical colitis activity index was used to determine disease severity. Three dietary patterns were identified based on the factor analysis: healthy, unhealthy and Western dietary pattern. After adjusting for potential confounding factors, patients who were in the highest tertile of healthy dietary pattern compared with the lowest tertile were 92 % less likely to have severe UC (OR: 0·08; 95 % CI: 0·03, 0·22). Also, those in the highest tertile of the Western dietary pattern were 3·86 times more likely to have severe UC than those in the lowest tertile (OR: 3·86; 95 % CI: 1·86, 8·00). Even after controlling for confounding variables, unhealthy dietary pattern did not increase the risk of severe UC. Our data indicate the beneficial role of healthy dietary pattern in amelioration of disease severity in UC patients. To confirm this association, more studies are needed, especially prospective cohort studies.

Calcium deficiency is associated with malnutrition risk in patients with inflammatory bowel disease

BACKGROUND AND AIM

Patients with inflammatory bowel disease (IBD) often have the condition of malnutrition, which can be presented as sarcopenia, micronutrient deficiencies, etc. Trace elements (magnesium, calcium, iron, copper, zinc, plumbum and manganese) belonging to micronutrients, are greatly vital for the assessment of nutritional status in humans. Trace element deficiencies are also the main manifestation of malnutrition. Calcium (Ca) has been proved to play an important part in maintaining body homeostasis and regulating cellular function. However, there are still a lack of studies on the association between malnutrition and Ca deficiency in IBD. This research aimed to investigate the role of Ca for malnutrition in IBD patients.

METHODS

We prospectively collected blood samples from 149 patients and utilized inductively coupled plasma mass spectrometry to examine their venous serum trace element concentrations. Logistic regression analyses were used to investigate the association between Ca and malnutrition. Receiver operating characteristic (ROC) curves were generated to calculate the cutoffs for determination of Ca deficiency.

RESULTS

Except Ca, the concentrations of the other six trace elements presented no statistical significance between non-malnutrition and malnutrition group. In comparison with the non-malnutrition group, the serum concentration of Ca decreased in the malnutrition group (89.36 vs 87.03 mg/L, p = 0.023). With regard to ROC curve, Ca < 87.21 mg/L showed the best discriminative capability with an area of 0.624 (95% CI: 0.520, 0.727, p = 0.023). Multivariate analyses demonstrated that Ca < 87.21 mg/L (OR = 3.393, 95% CI: 1.524, 7.554, p = 0.003) and age (OR = 0.958, 95% CI: 0.926, 0.990, p = 0.011) were associated with malnutrition risk. Serum Ca levels were significantly lower in the malnutrition group than those in the non-malnutrition group among UC patients, those with severe disease state or the female group.

CONCLUSIONS

In patients with IBD, Ca deficiency is an independent factor for high malnutrition risk.

Dietary flavonoids-microbiota crosstalk in intestinal inflammation and carcinogenesis

Colorectal cancer (CRC) is currently the third leading cancer and commonly develops from chronic intestinal inflammation. A strong association was found between gut microbiota and intestinal inflammation and carcinogenic risk. Flavonoids, which are abundant in vegetables and fruits, can inhibit inflammation, regulate gut microbiota, protect gut barrier integrity, and modulate immune cell function, thereby attenuating colitis and preventing carcinogenesis. Upon digestion, about 90% of flavonoids are transported to the colon without being absorbed in the small intestine. This phenomenon increases the abundance of beneficial bacteria and enhances the production of short-chain fatty acids. The gut microbe further metabolizes these flavonoids. Interestingly, some metabolites of flavonoids play crucial roles in anti-inflammation and anti-tumor effects. This review summarizes the modulatory effect of flavonoids on gut microbiota and their metabolism by intestinal microbe under disease conditions, including inflammatory bowel disease, colitis-associated cancer (CAC), and CRC. We focus on dietary flavonoids and microbial interactions in intestinal mucosal barriers as well as intestinal immune cells. Results provide novel insights to better understand the crosstalk between dietary flavonoids and gut microbiota and support the standpoint that dietary flavonoids prevent intestinal inflammation and carcinogenesis.

Dietary Patterns and Risk of Inflammatory Bowel Disease: A Systematic Review of Observational Studies

BACKGROUND

The incidence of inflammatory bowel disease (IBD) is increasing worldwide. Dietary patterns may be associated with odds of this disease. Although previous reviews have attempted to summarize the evidence in this field, the growing body of investigations prompted us to conduct an updated comprehensive systematic review.

METHODS

We used the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines to evaluate the association between dietary patterns before disease onset and the risk of IBD. PubMed, SCOPUS, and Web of Science were searched using structured keywords up to November 20, 2023.

RESULTS

Twenty-four publications (13 case-control, 1 nested case-control, and 10 cohort studies) were included in this review. The sample size of these studies ranged from 181 to 482 887 subjects. The findings were inconsistent across the included studies, showing inverse, direct, or no association between different dietary patterns and the risk of IBD.

CONCLUSIONS

This review provides comprehensive data on the link between dietary patterns prior to IBD diagnosis and risk of this condition. The explicit finding of present review is the extent gap in our knowledge in this field. Therefore, large-scale, high-quality studies are warranted to improve our understanding of the relationship between dietary patterns and IBD risk.

Impact of Folate Intake on Bone Mineral Density in Patients with Inflammatory Bowel Disease

BACKGROUND

Decreased bone mineral density (BMD) is a common problem among patients with inflammatory bowel disease (IBD). We hypothesised that an insufficient intake of folate might affect BMD.

METHODS

The study subjects included 26 with Crohn's disease-CD, 30 with ulcerative colitis-UC, and 31 healthy adults (control group-CG) aged 18-50 years. Participants were asked to follow their usual diet, and dietary intake was assessed by a 4-day, 24 h dietary recall. All the participants filled in a questionnaire referring to folic acid supplementation. The BMD, T-score, and Z-score of the lumbar spine (L1-L4) and femoral neck (FN) were assessed.

RESULTS

We found significant differences in the body mass, BMI (body mass index), CRP (C-reactive protein), BMD, Z-score, and T-score of the L1-L4 and FN between groups. There were no differences in energy and folate intake or the percentage coverage of recommended dietary allowances (RDA) of folate in all groups. Moreover, 70% of patients with UC, 92% of patients with CD, and 77% of CG patients showed insufficient folate intake. Folic acid was supplemented with a similar frequency in patients covering and not covering the RDA of folate. The intake of folate per 1000 kcal correlated positively with the CD group's BMD and T-score of L1-L4.

CONCLUSIONS

Insufficient folate intake is common in patients with IBD and healthy individuals. The impact of folate on BMD in IBD is not clear. We need more studies on the association between folate intake, folic acid concentration, and BMD in IBD.

Risk of avoidant/restrictive food intake disorder in patients with inflammatory bowel disease: predictive value of disease phenotype, disease activity and food literacy

BACKGROUND

Avoidant/Restrictive Food Intake Disorder (ARFID) is a newly described eating disorder. Adequate levels of food literacy allow individuals to have adequate food choices. This study aimed to assess the prevalence of ARFID and the level of food literacy in patients with inflammatory bowel disease (IBD) and to analyse the correlation between ARFID and food literacy.

METHOD

This cross-sectional study screened for ARFID and assessed food literacy levels in patients with IBD attending four tertiary hospitals in China. ARFID risk was measured using the Nine Item Avoidant/Restrictive Food Intake Disorder Screen (NIAS). Food literacy was assessed using the Food Literacy Evaluation Questionnaire (Chinese version, FLEQ-Ch).The relationship between individual NIAS scores and food literacy variables was analysed to assess which food literacy aspect is positively or negatively associated with NIAS scores. Stepwise linear regression analysis was performed to identify the possible predictors of NIAS scores in patients with IBD.

RESULT

A total of 372 IBD subjects completed the NIAS and FLEQ-Ch. The overall mean NIAS scores for the IBD cohort was 28.16 ± 8.03 (p < 0.01), and of the 372 participants, 123 (32.5%) had positive ARFID risk scores (≥ 10 NIAS-picky eating, ≥ 9 NIAS-poor appetite, and ≥ 10 NIAS-fear of negative consequences).The NIAS scores were inversely associated with food literacy levels (β =  - 0.299; p < 0.01).Disease phenotype, disease activity, and food literacy in patients with IBD provided valuable predictive insights for avoiding positive outcomes in ARFID.

CONCLUSION

This study shows that the risk of ARFID in the cohort of patients with IBD is associated with their inadequate food literacy levels. Therefore, this study supports the notion that patients with IBD should be assessed for food literacy regardless of whether they are currently diagnosed with ARFID. Specifically, for early identification of those at risk for ARFID in IBD, disease phenotype, disease activity, and food literacy should be routinely considered in clinical practice.The food literacy awareness of patients must be investigated and improved to predict the risk occurrence of ARFID and encourage healthy eating behaviour.

Anemia and frailty in the aging population: implications of dietary fiber intake (findings of the US NHANES from 2007-2018)

BACKGROUND

Frailty has long been seen as an indicator of reduced physical functions in the elderly, which may be caused by a variety of chronic illnesses or cancerous tumors. Dietary fiber was connected with anemia and frailty, whereas it was uncertain if dietary fiber consumption modifies the impact of anemia on frailty in elderly adults.

METHODS

We performed a secondary analysis using older adults aged 60 years and over from the National Health and Nutrition Examination Survey (NHANES) 2007-2018 cycles. Dietary fiber intake was estimated using two 24-h dietary recalls. Participants were dichotomized as frail or non-frail based on a modified Fried physical frailty phenotype from previous NHANES studies. The weighted logistic regression was used to estimate the odds ratio (OR) and confidence interval (CI) for the associations between hemoglobin levels and frailty at high- and low-dietary fiber intake levels.

RESULTS

A total of 9644 older adults were included in this study, and the weighted sample was 56,403,031, of whom 3,569,186 (6.3%) were deemed to be frail, and the remainder were deemed to be non-frail. Among the low dietary fiber intake group, higher hemoglobin was significantly associated with a lower risk of frailty (OR = 0.79, 95% CI: 0.71-0.87), and anemia was associated with an almost threefold elevated risk of frailty (OR = 3.24, 95% CI:1.98-5.29) in the fully adjusted model. However, this phenomenon was not observed in groups with high dietary fiber intake. In addition, L-shaped dose response relationship was found in the high dietary fiber intake group (P overall association < 0.001; P non-linear association = 0.076). Whereas the dose response relationship was not significant in the high dietary fiber intake group (P overall association 0.752; P non-linear association = 0.734).

CONCLUSIONS

Frailty was positively associated with the severity of anemia in older adults with low, but not high, dietary fiber intake. Adequate fiber intake may be an innovative dietary strategy to reduce frailty in older adults.

Physical activity, quality of diet and bone mineral density in patients with inflammatory bowel disease

BACKGROUND

The aim of this study was to find an association between moderate, vigorous and total physical activity (PA); diet quality; and bone mineral density (BMD) among patients suffering from inflammatory bowel disease (IBD).

METHODS

We enrolled 54 IBD patients, including those with Crohn's disease (CD) and ulcerative colitis (UC), and 24 healthy adults. All subjects completed the Questionnaire of Eating Behaviour based on which prohealthy and nonhealthy diet indexes were calculated, and the questionnaire included questions from the International Physical Activity Questionnaire. Prohealthy and nonhealthy diet indexes were divided into low-, medium- and high scores. BMD and T- and Z-scores of the lumbar spine (L1-L4) and femoral neck (FN) were assessed using dual-energy X-ray absorptiometry method.

RESULTS

BMD, T- and Z-scores of the FN and the Z-score of L1-L4 were significantly lower among patients with CD and UC than healthy controls. We did not find any differences in the time of PA among CD, UC and control groups (CG). The prohealthy diet index was higher among healthy subjects than the CD and UC groups. The nonhealthy diet index was lower among UC patients compared with the CG or CD patients. Prohealthy diet index positively correlated with BMD and T- and Z-scores of L1-L4 and FN in IBD. The prohealthy diet index correlated negatively with C-reactive protein and positively with body mass index. The prohealthy diet index correlated only with total PA in the CD group.

CONCLUSION

A well-balanced diet and proper PA may decrease the risk of osteoporosis in IBD, so education of patients referring to nutrition and PA is needed.

Nutrition, Nutritional Status, Micronutrients Deficiency, and Disease Course of Inflammatory Bowel Disease

During the disease course, most Inflammatory Bowel Disease patients present a condition of malnutrition, undernutrition, or even overnutrition. These conditions are mainly due to suboptimal nutritional intake, alterations in nutrient requirements and metabolism, malabsorption, and excessive gastrointestinal losses. A suboptimal nutritional status and low micronutrient serum levels can have a negative impact on both induction and maintenance of remission and on the quality of life of Inflammatory Bowel Disease patients. We performed a systematic review including all the studies evaluating the connection between nutrition, nutrition status (including undernutrition and overnutrition), micronutrient deficiency, and both disease course and therapeutic response in Inflammatory Bowel Disease patients. This systematic review was performed using PubMed/MEDLINE and Scopus. Four main clinical settings concerning the effect of nutrition on disease course in adult Inflammatory Bowel Disease patients were analyzed (induction of remission, maintenance of remission, risk of surgery, post-operative recurrence, and surgery-related complications). Four authors independently reviewed abstracts and manuscripts for eligibility. 6077 articles were found; 762 duplicated studies were removed. Out of 412 full texts analyzed, 227 were included in the review. The evidence summarized in this review showed that many nutritional aspects could be potential targets to induce a better control of symptoms, a deeper remission, and overall improve the quality of life of Inflammatory Bowel Disease patients.

High-Fiber Diet and Crohn's Disease: Systematic Review and Meta-Analysis

Crohn's disease (CD) is a subtype of inflammatory bowel disease (IBD). CD is a health problem in Western countries such as the US and European nations and is an idiopathic disease; however, certain cases of CD have been associated with intestinal dysbiosis. A systematic review with a meta-analysis was carried out to determine the efficacy of a diet rich in fiber with or without cointervention to improve remission rates for CD. The literature in the PubMed, Scopus, Web of Science, and ClinicalTrials databases was reviewed. The quality of the studies was evaluated using the Johanna Briggs Institute (JBI) scale. This review was conducted in accordance with the structure outlined in the PRISMA statement. In addition, a meta-analysis was performed with a 95% confidence interval (CI) and a random effects model. Eleven studies were included, totaling 2389 patients with CD. Applying a diet rich in fiber with or without the administration of routine therapies improved CD remission rates. Data regarding CD activity, remission time, and adverse effects derived from fiber consumption were analyzed. Consumption of fiber in the diet could improve remission rates for CD patients who receive or do not receive other treatment to maintain remission.

Low Vitamin K and Vitamin D Dietary Intake in Patients with Inflammatory Bowel Diseases

The inadequate dietary intake of Vitamin D and Vitamin K is an easily reversible factor favoring IBD-associated bone loss, but data on Vitamin K are lacking. A 28-item quantitative food frequency questionnaire was administered to 193 IBD patients (89 Crohn’s disease and 104 ulcerative colitis), and 199 controls. Patients’ demographics, clinical and laboratory findings were analyzed in relation to recommended daily allowances. VitD intake was inadequate both in the IBD and control patients (8.3 ± 4.5 µg/day in IBD, 53.1% RDA, and 9.7 ± 5.9 µg/day, 63.2% RDA, respectively). Conversely, the mean ViK intake was less than adequate in IBD, at 116.7 ± 116.3 µg/day (78.7% RDA), and high in controls, at 203.1 ± 166.9 µg/day (138.8% RDA). Nonetheless, due to marked inter-individual differences, diets were severely lacking VitK in 40% of UC and 49% of CD patients, more so in females and those with active disease. The intake of Vit D was non-significantly lower in colitis than that in Crohn’s disease (7.9 vs. 8.7 µg/day). The opposite was observed for VitK (123.5 vs. 107.0 µg/day). Thus, the diet lacks the micronutrients involved in bone wellbeing in a large proportion of IBD patients. While VitD supplementation is the rule, VitK shortages need proactive nutritional intervention.

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.

Clustering of Health and Oral Health-Compromising Behaviours in Army Personnel in Central Peninsular Malaysia

Health- and oral health-compromising behaviours (HOHCBs) impact the health readiness of military personnel, resulting in decreased fitness performance, thus affecting combat readiness. This study aimed to identify the clustering patterns and number of HOHCBs in army personnel in Central Peninsular Malaysia. Thus, a cross-sectional study using a multistage sampling technique and a validated 42-item online questionnaire was conducted to assess ten health (medical screening, physical activity, sedentary lifestyle, smoking status, alcohol consumption, substance abuse, aggressive behaviours, sleep, and road safety habits) and five oral health behaviour domains (tooth brushing, fluoridated toothpaste use, flossing, dental visits, and bruxism). Each HOHCB was dichotomised into healthy and health-compromising behaviour and analysed using hierarchical agglomerative cluster analysis (HACA). With the majority being males (92.5%), of other ranks (96.8%), and healthy (83.9%), 2435 army members of a mean age of 30.3 years (SD = 5.9) participated, with a response rate of 100%. HACA identified two clustering patterns: (i) 'high-risk behaviours' (30 HOHCBs) and (ii) 'most common risk behaviours' (12 HOHCBs) with a mean clustering number of 14.1 (SD = 4.1). In conclusion, army personnel in Central Peninsular Malaysia displayed 2 broad HOHCB clustering patterns, 'high-risk' and 'most common risk', with an average of 14 HOHCB clusters per person.

Dietary Habit Modifications in Paediatric Patients after One Year of Treatment with the Crohn's Disease Exclusion Diet

Gut microbiota alterations play a key role in the pathogenesis of inflammatory bowel disease (IBD), and its modification through specific diets is an emerging line of treatment that is currently being researched. The aim of this study was to assess changes in the dietary habits of patients with Crohn's disease (CD) and their long-term adherence to dietary therapy with the Crohn's disease exclusion diet (CDED) after one year. To analyse the modification of dietary habits and adherence to the Mediterranean diet (DM), the KIDMED questionnaire, a food consumption frequency questionnaire, was used. Twenty-four hour recalls at two timepoints, namely prior to the start of the dietary therapy and one year later, were also carried out. The processing degrees of the foods consumed by the patients were analysed at both timepoints using the NOVA classification system. Data from 24 patients (15 boys), with a mean age of 12.7 ± 2.9 years at the start of the dietary therapy, were analysed. All patients showed an improvement in their dietary pattern in the form of a reduction in the intake of ultra-processed foods (UPFs); a higher adherence to the MD; a decrease in the intake of cold meats, seafood, pasta, precooked foods, soft drinks, and pastries; an increase in the intake of eggs, legumes, dairy products, and nuts (p < 0.05); and adequate adherence, even in the long-term, to foods allowed during the different phases of the dietary regimen. Although more factors have an impact on the course of the disease in these patients, improving their dietary habits is essential.

Role of perioperative nutritional status and enteral nutrition in predicting and preventing post-operative complications in patients with Crohn's disease

Background

Perioperative immune-nutritional status is correlated with post-operative outcomes. This study aimed to evaluate whether pre-operative nutritional status could predict post-operative complications in patients with Crohn's disease (CD) and whether pre-operative enteral nutrition (EN) can prevent post-operative complications.

Methods

This retrospective cohort study analyzed the electronic health records of 173 patients diagnosed with CD in Ruijin Hospital, Shanghai, China, between August 2015 and May 2021: 122 patients had pre-operative nutritional support while 51 patients underwent surgery without pre-operative nutritional support. The pre-operative nutritional status, disease activity index, disease-related data, frequency of multiple surgery, operative data, and post-operative characters in each group were compared to determine whether the nutritional support and status could significantly affect post-operative outcome. One-to-one propensity score matching (PSM) was performed to limit demographic inequalities between the two groups.

Results

After PSM, no statistically significant differences were found in pre-operative patient basic characteristics between the two groups of 47 patients (98 patients in all) included in this study. Overall, 21 patients developed 26 post-operative complications. In terms of pre-operative nutritional status, the level of serum albumin (ALB), pre-albumin (pre-ALB), and hemoglobin (Hb) in the nutrition group were statistically higher than that in the control group. We also observed a statistically significant decrease in post-operative complications, need for emergency surgery, and staged operations, while the rate of laparoscopic surgery was higher in the nutrition group compared to the non-nutritional group. Post-operative complications were related to pre-operative nutritional condition, which indicated that EN may improve the nutritional status and reduced the rate of post-operative complications.

Conclusion

Pre-operative nutritional status is correlated with post-operative outcomes while EN plays a positive role in preventing the post-operative complications. EN is useful for improving the pre-operative nutritional status and reducing the post-operative adverse events for CD patients undergoing surgery.

Prevalence of vitamin D deficiency and modifiable risk factors in patients with Crohn's disease: A prospective observational study

AIMS

To determine the prevalence of vitamin D deficiency in adults with Crohn's Disease (CD) in Birmingham, UK (latitude 52.4°N, -1.9°E) and identify modifiable risk factors.

DESIGN/METHOD

A nurse-led, single-centre, prospective study was conducted over 5 months in 2019 and 2020 in outpatients with CD, at a tertiary referral hospital in Birmingham UK. Vitamin D (25OHD) levels were measured at a single timepoint by a dried blood spot sample. Modifiable risk factor data were collected including intake of vitamin D-containing foods, use of vitamin D supplements, sun exposure and current smoking.

RESULTS

Total 150 participants (53.3% male, 79.3% white British). Vitamin D deficiency (25OHD <50 nmol/L) was found in 53.3%. 32.7% of participants took over-the-counter vitamin D supplements and 20.7% used prescribed supplements. We found that diets were generally poor in relation to vitamin D-rich foods. In terms of sun exposure, few (18%) had visited a sunny country recently, and few (6%) covered their whole body with clothing. Most used High Sun Protection Factor (80%) with a median grade of SPF 45.

CONCLUSION

Patients with CD are at high risk of vitamin D deficiency as defined by 25OHD < 50 nmol/L, with the prevalence of deficiency being highest during the winter months. Patients with CD in the UK are unlikely to maintain vitamin D levels from sunlight exposure, dietary sources or over-the-counter supplements.

IMPACT

Patients with Crohn's Disease are at high risk of developing vitamin D deficiency but there is little data from the UK at this latitude. We demonstrate the prevalence and severity of vitamin D deficiency in people with Crohn's Disease in the UK. The prevalence of vitamin D deficiency in this group is high and warrants monitoring by nurses and clinical teams. Nurses and clinical teams should consider strategies for vitamin D supplementation in patients with Crohn's Disease.

Relationship between Undernutrition and Anemia in Patients with Ulcerative Colitis

This study aimed to assess the relationship between malnutrition and anemia in patients with ulcerative colitis (UC). The cross-sectional retrospective study included 80 patients with UC. Body mass index and total body fat mass were derived retrospectively from bioimpedance measurements. Anemia was diagnosed retrospectively according to WHO criteria. A binary logistic regression was performed to study the relationship between nutritional status parameters and anemia, and adjusted for demographic and disease-associated characteristics. The prevalence of anemia in the study population was 40.0%. Among all included patients, 86.3% had acute disease corresponding to S1–S3 disease behavior. In the adjusted binary logistic model, total serum protein level below 64 g/L and low body fat percentage were associated with high odds for the of development of anemia, with odds ratios of 5.1 (95% CI 1.5; 17.8; p = 0.01) and 8.5 (95% CI 1.1; 63.6; p = 0.037), respectively. The adjusted model included sex, age, disease activity, extent of gut involvement, quantity of relapses from disease onset, and treatment with immunosuppressive drugs as confounders. Hypoproteinemia and low body fat percentage were associated with anemia in patients with UC. These results suggested that undernutrition may be involved as one of the causative factors of anemia in UC.

Assessment of Dietary Adequacy and Quality in a Sample of Patients with Crohn's Disease

Both under-and over-nutrition are prevalent in patients with Crohn's Disease (CD). The aim of the present study was to evaluate dietary intake and compare it with relevant recommendations during active disease and remission, also taking into consideration the adequacy of energy reporting. Dietary quality was assessed through adherence to the Mediterranean diet and to the European dietary guidelines for cardiovascular disease prevention (CVD-score). Malnutrition was diagnosed with the GLIM criteria. There were 237 patients evaluated (54.9% males, 41.3 ± 14.1 years and 37.6% with active disease). In the total sample, high prevalence of overweight/obesity (61.6%) and low prevalence of malnutrition (11.4%) were observed, whereas 25.5% reported low protein intake in the sub-sample of adequate energy reporters. The mean MedDietScore was 28.0 ± 5.5 and the mean CVD-score was 5.25 ± 1.36, both reflecting moderate dietary quality. Patients with active disease reported higher prevalence of low protein intake, lower carbohydrate, fibers, fruits, vegetables, legumes, and sweets consumption and a lower MedDietScore compared to patients in remission. Consumption of fibers, fruits, vegetables, and legumes while in remission did not result in reaching the recommended intakes, and dietary quality was low as reflected by the MedDietScore. In conclusion, both protein undernutrition and energy overconsumption were prevalent in the current sample and overall patients adhered to a moderate quality diet irrespective of disease stage.

Genetic Aspects of Micronutrients Important for Inflammatory Bowel Disease

Inflammatory bowel disease (IBD), Crohn’s disease (CD) and ulcerative colitis (UC) are complex diseases whose etiology is associated with genetic and environmental risk factors, among which are diet and gut microbiota. To date, IBD is an incurable disease and the main goal of its treatment is to reduce symptoms, prevent complications, and improve nutritional status and the quality of life. Patients with IBD usually suffer from nutritional deficiency with imbalances of specific micronutrient levels that contribute to the further deterioration of the disease. Therefore, along with medications usually used for IBD treatment, therapeutic strategies also include the supplementation of micronutrients such as vitamin D, folic acid, iron, and zinc. Micronutrient supplementation tailored according to individual needs could help patients to maintain overall health, avoid the triggering of symptoms, and support remission. The identification of individuals’ genotypes associated with the absorption, transport and metabolism of micronutrients can modify future clinical practice in IBD and enable individualized treatment. This review discusses the personalized approach with respect to genetics related to micronutrients commonly used in inflammatory bowel disease treatment.

Improving Food-Related Quality of Life in Inflammatory Bowel Disease through a Novel Web Resource: A Feasibility Randomised Controlled Trial

Food-related quality of life (FR-QoL) is impaired in inflammatory bowel disease (IBD) and education and support on food-related issues in IBD is needed. This feasibility trial aimed to investigate the effectiveness and acceptability of a web resource in enhancing FR-QoL in newly diagnosed IBD. Patients diagnosed with Crohn's disease or ulcerative colitis in the preceding 12 months, with an impaired FR-QoL, were recruited and randomised to either receive access to the web resource (covering IBD-specific diet concerns) or no access (control group) for 12 weeks, while receiving usual clinical care. FR-QoL, health-related quality of life, psychological outcomes, and clinical disease activity were assessed. Web resource usage was assessed, and patients' experiences of the web resource were investigated in semi-structured interviews. Of 81 patients screened, 50 participants were randomised, 30 to the web resource and 20 to control. FR-QoL increased more in the web resource (+11.7 SD 18.2) than control group (+1.4 SD 20.4) (p = 0.067), while IBD distress reduced in the web resource (-6.8 SD 26.6) and increased in the control group (+8.3 SD 25.5) (p = 0.052), albeit not statistically significantly. End of trial Crohn's disease clinical activity (PRO-2) was significantly lower in the web resource than control group (p = 0.046). Participants most frequently accessed web resource content discussing dietary management of gut symptoms and in semi-structured interviews, reported the website to contain relevant information. This feasibility study demonstrates potential effectiveness of the web resource on improving FR-QoL and psychological outcomes in IBD. An adequately powered effectiveness RCT is feasible to conduct and is now warranted. NCT03884686.

The Relationship between Gastrointestinal Health, Micronutrient Concentrations, and Autoimmunity: A Focus on the Thyroid

Currently, there is a lack of understanding of why many patients with thyroid dysfunction remain symptomatic despite being biochemically euthyroid. Gastrointestinal (GI) health is imperative for absorption of thyroid-specific nutrients as well as thyroid function directly. This comprehensive narrative review describes the impact of what the authors have conceptualized as the “nutrient–GI–thyroid axis”. Compelling evidence reveals how gastrointestinal health could be seen as the epicenter of thyroid-related care given that: (1) GI conditions can lower thyroid-specific nutrients; (2) GI care can improve status of thyroid-specific nutrients; (3) GI conditions are at least 45 times more common than hypothyroidism; (4) GI care can resolve symptoms thought to be from thyroid dysfunction; and (5) GI health can affect thyroid autoimmunity. A new appreciation for GI health could be the missing link to better nutrient status, thyroid status, and clinical care for those with thyroid dysfunction.

Bone Marrow Mesenchymal Stem Cells (BMSC) Carried with miR-338 Improve BMSC Homing in Intestinal Mucosa of Inflammatory Bowel Disease (IBD) Rats Through Increasing C-X-C Chemokine Receptor Type 4 (CXCR-4)

This study assessed whether bone marrow mesenchymal stem cells (BMSC) carried with miR-338 improve its homing in intestinal mucosa of IBD rats. Fifty SD rats were equally and randomly assigned into control set, model set, miR-338 set, CXCR-4 Inhibitor set and positive control set followed by analysis of miR-338 expression, body weight, DAI grade, pathological changes of distal colonic tissue, ultra-microstructure of intestinal epithelium, level of IL-8, IL-10, TGF-β1, VEGF, and CXCR4, as well as the relation between miR-338 and CXCR-4. miR-338 in decorated BMSC was significantly upregulated. Body weight in model set and CXCR-4 Inhibitor set was lowest followed by miR-338 set and positive control set. However, opposite results were obtained for DAI grade. IL-8 level was highest and IL-10 was lowest in model set and CXCR-4 Inhibitor set. The BMSC carried with miR-338 exerted recovery action on the intestinal mucosa of IBD rats and inhibited the activity of inflammatory cells. In conclusion, BMSC carried with miR-338 develops recovery action on the intestinal mucosa of IBD rats possibly through regulation of CXCR4, indicating that miR-338 might be a target for the treatment of IBD.

Mucolytic bacteria license pathobionts to acquire host-derived nutrients during dietary nutrient restriction

Pathobionts employ unique metabolic adaptation mechanisms to maximize their growth in disease conditions. Adherent-invasive Escherichia coli (AIEC), a pathobiont enriched in the gut mucosa of patients with inflammatory bowel disease (IBD), utilizes diet-derived L-serine to adapt to the inflamed gut. Therefore, the restriction of dietary L-serine starves AIEC and limits its fitness advantage. Here, we find that AIEC can overcome this nutrient limitation by switching the nutrient source from the diet to the host cells in the presence of mucolytic bacteria. During diet-derived L-serine restriction, the mucolytic symbiont Akkermansia muciniphila promotes the encroachment of AIEC to the epithelial niche by degrading the mucus layer. In the epithelial niche, AIEC acquires L-serine from the colonic epithelium and thus proliferates. Our work suggests that the indirect metabolic network between pathobionts and commensal symbionts enables pathobionts to overcome nutritional restriction and thrive in the gut.

Gut Microbiota and Dietary Factors as Modulators of the Mucus Layer in Inflammatory Bowel Disease

The gastrointestinal tract is optimized to efficiently absorb nutrients and provide a competent barrier against a variety of lumen environmental compounds. Different regulatory mechanisms jointly collaborate to maintain intestinal homeostasis, but alterations in these mechanisms lead to a dysfunctional gastrointestinal barrier and are associated to several inflammatory conditions usually found in chronic pathologies such as inflammatory bowel disease (IBD). The gastrointestinal mucus, mostly composed of mucin glycoproteins, covers the epithelium and plays an essential role in digestive and barrier functions. However, its regulation is very dynamic and is still poorly understood. This review presents some aspects concerning the role of mucus in gut health and its alterations in IBD. In addition, the impact of gut microbiota and dietary compounds as environmental factors modulating the mucus layer is addressed. To date, studies have evidenced the impact of the three-way interplay between the microbiome, diet and the mucus layer on the gut barrier, host immune system and IBD. This review emphasizes the need to address current limitations on this topic, especially regarding the design of robust human trials and highlights the potential interest of improving our understanding of the regulation of the intestinal mucus barrier in IBD.