Early experience with a low FODMAP diet in Asian patients with irritable bowel syndrome

The efficacy and real-world effectiveness of a diet low in fermentable oligo-, di-, monosaccharides and polyols in irritable bowel syndrome: A systematic review and meta-analysis

BACKGROUND & AIMS

A diet low in fermentable oligo-, di-, monosaccharides, and polyols (LFD) has been shown to effectively reduce irritable bowel syndrome (IBS) symptoms. Effects resulting from real-world studies may differ from those seen in efficacy studies because of the diversity of patients in real-world settings. This systematic review and meta-analysis aimed to compare the effect of the LFD on reducing IBS symptoms and improving the quality of life (QoL) in efficacy trials and real-world studies.

METHODS

Major databases, trial registries, dissertations, and journals were systematically searched for studies on the LFD in adults with IBS. Meta-analysis was conducted using a random effects model with standardized mean differences (SMD) and 95% confidence intervals (CI). Outcomes of interest were all patient-reported: stool consistency, stool frequency, abdominal pain, overall symptoms, adequate symptom relief, IBS-specific QoL and adherence to the LFD.

RESULTS

Eleven efficacy and 19 real-world studies were reviewed. The meta-analysis results for abdominal pain (SMD 0.35, 95% CI 0.16 to 0.54) and QoL (SMD 0.23, 95% CI -0.05 to 0.50) showed the LFD was beneficial in efficacy studies with no statistically significant results for stool frequency (SMD 0.71, 95% CI 0.34 to 1.07). Real-world studies found improvements in abdominal pain and QoL. Due to heterogeneity, no meta-analysis was done for stool consistency and overall symptoms. In these outcomes, results were mostly supportive of the LFD, but they were not always statistically significant.

CONCLUSIONS

The results of this systematic review and meta-analysis suggest the LFD improves outcomes compared to a control diet (efficacy studies) or baseline data (real-world studies). Because of diverse study designs and heterogeneity of results, a clear superiority of the LFD over control diets could not be concluded. There are no indications of an efficacy-effectiveness gap for the LFD in adults with IBS.

A randomized, double-blinded, placebo-controlled clinical trial on Lactobacillus-containing cultured milk drink as adjuvant therapy for depression in irritable bowel syndrome

Irritable bowel syndrome (IBS) is frequently linked with coexisting mental illnesses. Our previous study discovered that 32.1% of IBS patients had subthreshold depression (SD), placing them at higher risk of developing major depression. Gut microbiota modulation through psychobiotics was found to influence depression via the gut-brain axis. However, the efficacy of lessening depression among IBS patients remains ambiguous. The study's aim was to investigate the roles of cultured milk drinks containing 109 cfu Lactobacillus acidophilus LA-5 and Lactobacillus paracasei L. CASEI-01 on depression and related variables among IBS participants with SD. A total of 110 IBS participants with normal mood (NM) and SD, were randomly assigned to one of four intervention groups: IBS-NM with placebo, IBS-NM with probiotic, IBS-SD with placebo, and IBS-SD with probiotic. Each participant was required to consume two bottles of cultured milk every day for a duration of 12 weeks. The following outcomes were assessed: depression risk, quality of life, the severity of IBS, and hormonal changes. The depression scores were significantly reduced in IBS-SD with probiotic and placebo from baseline (p < 0.001). Only IBS-SD with probiotic showed a significant rise in serotonin serum levels (p < 0.05). A significantly higher life quality measures were seen in IBS-SD with probiotic, IBS-SD with placebo, and IBS-NM with placebo (p < 0.05). All groups, both placebo and probiotic, reported significant improvement in IBS severity post-intervention with a higher prevalence of remission and mild IBS (p < 0.05). Dual strains lactobacillus-containing cultured milk drink via its regulation of relevant biomarkers, is a potential anti-depressive prophylactic agent for IBS patients at risk.

The impact of diet and ethnicity on gut microbiota variation in irritable bowel syndrome: A multi-center study

BACKGROUND AND AIM

The gut microbiota in irritable bowel syndrome (IBS) is known to vary with diet. We aim to (i) analyze the gut microbiota composition of IBS patients from a multi-ethnic population and (ii) explore the impact of a low FODMAP diet on gastrointestinal symptoms and gut microbiota composition among IBS patients.

METHODS

A multi-center study of multi-ethnic Asian patients with IBS was conducted in two phases: (i) an initial cross-sectional gut microbiota composition study of IBS patients and healthy controls, followed by (ii) a single-arm 6-week dietary interventional study of the IBS patients alone, exploring clinical and gut microbiota changes.

RESULTS

A total of 34 adult IBS patients (IBS sub-types of IBS-D 44.1%, IBS-C 32.4%, and IBS-M 23.5%) and 15 healthy controls were recruited. A greater abundance of Parabacteroides species with lower levels of bacterial fermenters and short-chain fatty acids producers were found among IBS patients compared with healthy controls. Age and ethnicity were found to be associated with gut microbiota composition. Following a low FODMAP dietary intervention, symptom and quality of life improvement were observed in 24 (70.6%) IBS patients. Symptom improvement was associated with adherence to the low FODMAP diet (46.7% poor adherence vs 92.9% good adherence, P = 0.014), and gut microbiota patterns, particularly with a greater abundance of Bifidobacterium longum, Anaerotignum propionicum, and Blautia species post-intervention.

CONCLUSION

Gut microbiota variation in multi-ethnic IBS patients may be related to dietary intake and may be helpful to identify patients who are likely to respond to a low FODMAP diet.

Clinical outcome of disorders of gut-brain interaction in secondary care: A longitudinal study

BACKGROUND

Real-world data on the outcome of routine treatment for disorders of gut-brain interaction (DGBI) in secondary care are lacking.

METHOD

A longitudinal study of consecutive adult patients with various DGBI attending this institution's gastroenterology clinic was conducted. Following 2 years of treatment, the proportion of patients with symptom improvement, details of clinical therapy, factors associated with and the impact of 'no symptom improvement' were determined.

RESULTS

A total of 289 patients (median age 68 years; 64.7% females; 28.4% irritable bowel syndrome (IBS), 20.1% functional dyspepsia (FD), 8.7% functional constipation (FC), 42.9% overlap syndrome) were recruited. After 2 years, 66.1% patients reported symptom improvement. Patients with overlap syndrome were less likely to have symptomatic improvement compared to those with a single DGBI (Overlap 55.6% vs IBS 74.4% vs FD 72.4% vs FC 76.0%, p = 0.014). Reassurance was associated with symptom improvement (p < 0.001). On multivariate analysis, overlap syndrome remained significantly associated with a poorer outcome (OR 2.27, 95% CI 1.22-4.25, p = 0.010), while providing reassurance was associated with a positive outcome (OR 0.30, 95% CI 0.16-0.56, p < 0.001). Only 25.6% and 14.9% of patients were referred for a low FODMAP diet and psychiatric intervention respectively. DGBI patients who had 'no improvement' were more likely to seek further GI consultations and had more work absenteeism.

CONCLUSION

Two-thirds of DGBI patients in secondary care showed symptom improvement. Patients who were reassured had better symptom improvement, while those with an overlap syndrome were associated with a poorer outcome, resulting in greater healthcare consultation and work absenteeism.

Effects of a Low-FODMAP Diet on Irritable Bowel Syndrome in Both Children and Adults-A Narrative Review

Irritable bowel syndrome is a typical gastrointestinal disease that causes bloating, flatulence, abdominal pain, diarrhoea, constipation, or alteration of the last two in adults and children. A diet low in fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAP) is one of the potential treatment strategies to reduce abdominal symptoms and increase the quality of life. The present narrative review aims to present a general overview of current studies that have evaluated the efficacy of a low-FODMAP diet against other diets in gastrointestinal symptoms, nutrient intake in adults and children, and lifestyle quality. The research was performed using seven searchable databases, which included the Cochrane Central Register of Controlled Trials (CENTRAL), Cochrane Database of Systematic Reviews (CDSR), Excerpta Medica Database (EMBASE), Medline, PubMed, Scopus, and Web of Science, up to March 2023. In conclusion, there is significant evidence that the follow-up of a low-FODMAP diet might be a feasible first-line therapeutic strategy to reduce stomach discomfort, pain, bloating, and quality of life for patients with irritable bowel syndrome.

Children with functional abdominal pain disorders successfully decrease FODMAP food intake on a low FODMAP diet with modest improvements in nutritional intake and diet quality

BACKGROUND

We sought to determine how a low fermentable oligosaccharide, disaccharide, monosaccharide, and polyol (FODMAP) diet (LFD) affected high FODMAP food intake, nutrient intake, and diet quality in children with functional abdominal pain disorders (FAPD).

METHODS

Children (ages 7-13 years) with Rome IV FAPD began a dietitian-guided LFD. Three-day food records were captured at baseline and 2-3 weeks into the LFD. Intake of high FODMAP foods, energy, macronutrients, micronutrients, food groups, and ultra-processed foods were determined.

KEY RESULTS

Median age of participants was 11 years, and 19/31 (61%) were female. Twenty-eight (90%) decreased high FODMAP food intake on the LFD: overall median (25-75%) high FODMAP foods/day decreased from 5.7 (3.6-7.3) to 2 (0.3-3.7) (p < 0.001). A more adherent subset (n = 22/71%) of participants consumed on average ≤3 high FODMAP foods per day during the LFD. Baseline nutritional intake and quality were generally poor with several micronutrient deficiencies identified. Diet quality improved on the LFD with increased servings of vegetables and protein and decreased consumption of ultra-processed foods, trans-fatty acids, and added sugars. On the LFD, there were significant decreases in total carbohydrates and thiamin (remained within recommended intake) and significant increases in vitamin B6 (p = 0.029), vitamin C (p = 0.019), and vitamin E (p = 0.009). Children more adherent to the LFD further increased vitamin D, magnesium, potassium, and fat servings.

CONCLUSIONS AND INFERENCES

The majority of children with FAPD on a dietitian-led LFD successfully decreased high FODMAP food intake. Children with FAPD on the LFD (vs. baseline) modestly improved micronutrient intake and diet quality.

The challenges of implementing low fermentable oligo-, di-, mono-saccharides and polyol diet in India: An analysis of available data

BACKGROUND

Low fermentable oligo-, di-, monosaccharides, and polyols (FODMAP) diet is used in irritable bowel syndrome (IBS). However, data on the utility and challenges of implementing such a diet in India are scanty. Since dietary practices in India are different from other Asian and Western countries, the existing Indian data were analyzed.

METHODS

This study attempted to analyze the existing Indian data on the frequency of vegetarianism, cereal (wheat vs. rice), milk/milk product consumption, and lactose malabsorption (LM). A 5-point scale (quiet easy, easy, moderately easy, not easy, difficult) for implementation of low FODMAP diet for IBS patients was proposed based on regional dietary diversity and LM in India.

RESULTS

Our analysis showed that vegetarianism is high in India with regional differences in frequency. Similarly, there is regional variation in frequency of LM though it is quite high in most parts of India where data are available. While southern, eastern, and north-eastern [corrected] parts of the country have rice as the staple cereal, wheat is consumed more in other parts. We suggest that implementing a low FODMAP diet in north-eastern India may be most easy compared to northern India, where it may be most difficult. Implementing a low FODMAP diet in southern and eastern India may be easy, moderately easy in western India, and not easy in central India.

CONCLUSIONS

The variation in the difficulty in implementing a low FODMAP diet in India may stem from the regional food preference and differences in vegetarianism, as well as frequency of LM.

Investigating the Role of Low-FODMAP Diet in Improving Gastrointestinal Symptoms in Irritable Bowel Syndrome

Background

A low–fermentable oligosaccharide, disaccharide, monosaccharide, and polyol (FODMAP) diet (LFD) appeared to improve gastrointestinal symptoms in patients with Irritable Bowel Syndrome (IBS). However, evidence of its efficacy in Asia remains scarce.

Objectives

This study aims to investigate the clinical effectiveness of LFD intervention among Asian IBS patients and barriers to its adherence.

Methods

Patients with IBS who were instructed to follow LFD by dietitians at a tertiary hospital in Singapore between July 2013 and December 2014 were retrospectively reviewed. Severity scores of 19 gastrointestinal symptoms were recorded using an 11-point rating scale (0 = “no symptoms,” 10 = “extremely severe”) pre- and post-LFD intervention. Adherence to LFD was assessed based on patients’ diet history and a high-FODMAP food checklist.

Results

Eighty-two patients with a median follow-up of 5.8 weeks were investigated. The LFD adherence rate was 61.0% ( n = 50). Overall, statistically significant improvement was observed in 14 of 19 gastrointestinal symptoms (median difference = −2.0 to −0.5, p < .05). The proportion of patients who had improvement in 10 individual symptoms (defined as ≥1 point reduction in symptom severity rating) was significantly higher in LFD-adherent patients (67.5%–82.4%) than that of the non-adherent group (27.8%–55.0%). Reasons reported for non-adherence included “limited availability of low-FODMAP alternatives” ( n = 9), “limited understanding of LFD” ( n = 7), and “perceived lack of benefit” ( n = 4).

Conclusions

LFD intervention improved gastrointestinal symptoms in a cohort of Asian IBS patients. Limited access to low-FODMAP alternatives was the main barrier to adherence.

Experiences of ethnic minority patients who are living with a primary chronic bowel condition: a systematic scoping review with narrative synthesis

Background

Prevalence of chronic gastrointestinal diseases has been rising amongst ethnic minority populations in Western countries, despite the first-generation migrants originating from countries of low prevalence. Differences caused by genetic, environmental, cultural, and religious factors in each context may contribute towards shaping experiences of ethnic minority individuals living with primary bowel conditions. This review aimed to explore the experiences of ethnic minority patients living with chronic bowel conditions.

Methods

We conducted a systematic scoping review to retrieve qualitative, quantitative, and mixed methods studies from eight electronic databases, and manually searched reference lists of frequently cited papers.

Results

Fourteen papers met the inclusion criteria: focussing on inflammatory bowel disease, irritable bowel syndrome, and coeliac disease. Core themes were narratively analysed. South Asians had limited understanding of inflammatory bowel disease and coeliac disease, hindered by language and literacy barriers, particularly for older generations, suggesting that culturally relevant information is needed. Family support was limited, and Muslim South Asians referred to religion to understand and self-manage inflammatory bowel disease. Ethnic minority groups across countries experienced: poor dietary intake for coeliac disease and inflammatory bowel disease, cultural conflict in self-managing diet for inflammatory bowel disease which increased anxiety, and there was a need for better quality of, and access to, healthcare services. British ethnic minority groups experienced difficulties with IBD diagnosis/misdiagnosis.

Conclusions

Cultural, religious, and social contexts, together with language barriers and limited health literacy influenced experiences of health inequalities for ethnic minority patients living with chronic bowel diseases.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-021-01857-8.

Low fermentable oligosaccharide, disaccharide, monosaccharide, and polyol diet in patients with diarrhea-predominant irritable bowel syndrome: A prospective, randomized trial

BACKGROUND AND AIM

Low fermentable oligosaccharide, disaccharide, monosaccharide, and polyol (FODMAP) diet improves irritable bowel syndrome (IBS) symptoms. Data on long-term "modified" FODMAP diet are emerging. We aimed to assess efficacy and acceptability of short-term "strict" low FODMAP diet (LFD) and long-term "modified" FODMAP diet in patients with diarrhea-predominant IBS (IBS-D).

METHODS

This prospective randomized trial included patients with IBS-D (Rome IV) and IBS severity scoring system (IBS-SSS) ≥ 175. In phase I (4 weeks), patients were randomized to strict LFD and traditional dietary advice (TDA) groups. From 4 to 16 weeks, LFD group was advised systematic reintroduction of FODMAPs ("modified" FODMAP diet). Response was defined as > 50-point reduction in IBS-SSS.

RESULTS

Of the total 166 patients with IBS-D screened, 101 (mean age 41.9 ± 17.1 years, 58% male) were randomized to LFD (n = 52) and TDA (n = 49) groups. Both at 4 and 16 weeks, total IBS-SSS and IBS quality of life score reduced significantly in both groups, but there was significantly greater reduction in LFD group. By intention-to-treat analysis, responders in LFD group were significantly higher than TDA group (4 weeks-62.7% [32/51] vs 40.8% [20/49], respectively, P = 0.0448; 16 weeks-52.9% [27/51] vs 30.6% [15/49], respectively; P = 0.0274). Compliance to LFD was 93% at 4 weeks and 64% at 16 weeks. Energy, carbohydrate, fat, and fiber intake showed reduction in LFD group at 4 weeks, which improved till 16 weeks.

CONCLUSIONS

Strict LFD for short-term and "modified" LFD for long term in IBS-D patients is acceptable and leads to significant improvement in symptoms and quality of life.

An evaluation of dietary adequacy among patients with constipation-predominant irritable bowel syndrome in Malaysia

Background/Aims

Substantial proportions of patients with constipation-predominant irritable bowel syndrome (IBS-C) linked their symptoms with particular intake of foods. However, there is lack of current data regarding the intake among IBS-C patients before any dietary interventions. Thus, this study aimed to evaluate the dietary adequacy among IBS-C against the standard recommended nutrient intake (RNI) and healthy controls.

Methods

A retrospective case-control study was conducted involving IBS-C patients and healthy control subjects. A validated 126-food items frequency questionnaire was administered to all the subjects to assess their dietary intake, guided by dietitians. The calculated nutrients intake for IBS-C patients was then compared against the standard RNI and healthy controls.

Results

A total of 306 subjects were recruited, among which 218 were diagnosed with IBS-C and 88 were included as healthy controls. IBS-C patients had significantly lower intake of wholegrain products, fried foods, dairy products, fruits, and vegetables compared to healthy controls. The daily intake of energy, certain macronutrients, and micronutrients among IBS-C patients was significantly lower than the healthy subjects. Less than 5% of IBS-C patients and healthy subjects achieved the standard recommendation for dietary fiber. Also, various vitamin intake (B₁, B₂, B₆, folate, B₁₂, E, K, and potassium) among IBS-C patients did not meet the standard RNI.

Conclusions

Dietary intakes of IBS-C patients did not meet the recommended intake for Malaysian and showed the nutritional inadequacies compared to the control subjects. Our study highlighted the importance of dietary evaluation prior to planning strategies for dietary intervention targeting IBS-C patients.

Global Dietary Patterns and Functional Gastrointestinal Disorders

Functional Gastrointestinal Disorders (FGIDs) are common. In the United States alone, approximately 25 million Americans are estimated to have at least one FGID. Nonpharmacological treatment options include psychological/behavioral approaches, and dietary interventions that can vary across countries. The aim of this review is to evaluate the available evidence for dietary interventions for the treatment of childhood FGIDs amongst various cultures and regions of the world. This review includes clinical trials of dietary therapies for the treatment of FGIDs in children posted on or before 13 July 2020 in PubMed. Overall, the consensus view suggests that the westernization of diets is linked to the development of FGIDs, and diets low in Fermentable Oligosaccharides, Disaccharides, Monosaccharides and Polyols (FODMAPs) may reduce abdominal symptoms. However, more work is needed to confirm these findings.

Literature Review: Dietary Intervention Adherence and Adherence Barriers in Functional Gastrointestinal Disorder Studies

Dietary management is key in controlling functional gastrointestinal disorders (FGIDs) symptoms. However, the degree to which patients with FGIDs in clinical studies adhere to dietary recommendations is unknown. Our aim was to evaluate adherence, dietary education, and adherence-related factors in FGIDs dietary intervention trials. A literature search was performed using MEDLINE, Google Scholar, and SCOPUS for clinical trials evaluating dietary management of FGIDs. Full manuscripts published from January 2000 through August 2018 were reviewed. Data including definitions of adherence and rates, study design, dietary education, use of a dietitian, provision of study foods, potential adherence barriers, and dropouts were captured. A total of 21 publications were included. Fifteen (67%) focused on the low fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAP) diet, 5 (24%) on fiber supplementation, and 1 (9%) on a low carbohydrate diet. Fifteen (71%) were randomized controlled trials. Meals/supplements were provided to the study participants in 27%, 80%, and 100%, of the low FODMAP, fiber, and low carbohydrate studies, respectively, which appeared to significantly enhance adherence (P<0.03). Eighteen studies (81%) provided either written or oral diet information to study participants. Overall, only 10 publications (48%) provided adherence data. Nine (60%) of the low FODMAP studies provided adherence data (range, 30% to 100%); ranges could not be calculated for the other dietary trials. The most common method to measure adherence was via food diaries. Therefore, adherence is not often measured in FGIDs dietary intervention clinical trials; when reported, rates of adherence range widely. Studies providing food had the highest adherence rates.

All that a physician should know about FODMAPs

A diet low in poorly absorbed, fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPs) is now considered as an effective strategy for symptoms control in patients with irritable bowel syndrome (IBS). The low FODMAP diet is administered in three phases, namely restriction of all dietary FODMAPs followed by rechallenge and then reintroduction of specific FODMAPs according to the tolerance of patients. A dietician should be involved in patients in whom a low FODMAP diet is planned. While restricting high FODMAPs, it is pertinent that patients are advised a well-balanced diet and suitable alternatives with low FODMAP contents in each food groups are prescribed. Strict adherence to a low FODMAP diet has been shown to improve symptoms, stool output, quality of life, and the overall well-being of patients with IBS. For those who do not respond to this dietary approach, a normal diet may be initiated and other treatment strategies (dietary or nondietary) should be considered. Interestingly, the low FODMAP diet has also been tried in other functional disorders, nonceliac gluten sensitivity, and even inflammatory bowel disease. Since the concept of FODMAP is relatively new, there is only limited data on the content of FODMAP in the Indian food items and there is a need to address this question. There is also a need for well-designed and adequately powered studies to explore the efficacy of low FODMAP diet in patients with IBS. In the present review article, we have compiled all the relevant information about FODMAPs with an objective to provide comprehensive information on FODMAPs to a physician.

Low fermentable oligosaccharides, disaccharides, monosaccharides, and polypols diet and irritable bowel syndrome in Asia

Functional bowel disorders, including irritable bowel syndrome (IBS), are a chronic condition that can significantly reduce patients' quality of life. Therefore, this paper will review the roles of a low fermentable oligosaccharides, disaccharides, monosaccharides, and polypols (FODMAP) diet in treating IBS, particularly in an Asian setting. About 20% of the general population is diagnosed with IBS. However, there are limited effective medical therapies available for treating IBS. Therefore, IBS presents a major challenge to the health-care providers. Recently, there is an increasing interest in the use of a diet low in FODMAP for the treatment of IBS. A low FODMAP diet can decrease the delivery of readily fermentable substrates to the small intestine and colon, thereby improving functional gastrointestinal symptoms.

Review article: implementation of a diet low in FODMAPs for patients with irritable bowel syndrome-directions for future research

BACKGROUND

Despite the efficacy of a diet low in fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAP) for patients with irritable bowel syndrome, many questions remain unanswered with respect to its clinical implementation.

AIM

To review literature to identify, synthesise, and provide direction for future research in the implementation and evaluation of the low FODMAP diet.

METHODS

Bibliographical searches were performed in Ovid Medline, CINAHL, Scopus and PubMed from database commencement until September 2018, with search terms focused on the population (irritable bowel syndrome) and intervention of interest (FODMAP).

RESULTS

Predictors of response to a low FODMAP diet remain under investigation, with preliminary data supporting faecal microbiota or faecal volatile organic compound profiling. Training of clinicians, and standards for the education of patients about the phases of a low FODMAP diet, as well as the role of Apps, require formal evaluation. There are limited data on the longer term efficacy and safety of the low FODMAP diet with respect to sustained symptom control, effect on quality of life and healthcare utilisation, nutritional adequacy, precipitation of disordered eating behaviours, effects on faecal microbiota and metabolomic markers, and subsequent translation to clinical effects.

CONCLUSIONS

Many gaps in implementation of the low FODMAP diet in clinical practice, as well as long-term safety and efficacy, remain for further investigation.