The efficacy and safety of vibrating capsules for functional constipation: a systematic review and meta-analysis of randomized controlled trials.

OBJECTIVE: Chronic constipation is a challenging functional gastrointestinal disorder that remains a global burden. Pharmacologic therapy, including laxatives and dietary fibers, are suggested as lines of treatment. Recent trials introduced an orally ingested vibrating capsule (VC) as an eligible option for chronic constipation management. METHODS: We conducted a literature search in English on electronic databases CENTRAL, PubMed, EMBASE, Scopus, and WOS until February 27th, 2023. RevMan was used to perform the meta-analysis. The results were reported as risk ratios (RRs), mean differences (MDs), and 95% confidence intervals (CIs). The study protocol was registered in PROSPERO with ID: (CRD42023409422). RESULTS: Three RCTs with a total of 601 patients were included in our analysis. There was no difference between the VC and placebo in responder rate (RR: 1.37 with 95% CI [0.82, 2.28], p = .22), CSBM change from baseline (MD: 0.21 with 95% CI [-0.26, 0.69], p = .38), SBM change from baseline (MD: 0.14 with 95% CI [-0.22, 0.49], p = .46), and the incidence of any adverse event (RR: 1.45 with a 95% CI of [0.79, 2.63], p = .23). However, VC was associated with increased vibration sensation (RR: 17.23, 95% CI [3.29, 90.20], p = .0008). CONCLUSIONS: VC was not effective to improve bowel movement in patients with functional constipation with no difference in response rate. However, evidence is still uncertain, with only three small RCTs that yielded heterogenous findings, mainly due to the different vibration protocols. Also, our findings suggest that VC is safe and well-tolerated, with no significant harmful effects observed. Therefore, more large-scale RCTs are needed to confirm the efficacy and safety of VC in patients with functional constipation, determining the most effective dose, frequency, and duration of treatment.

Tolerability and safety of a semi-elemental enteral formula with partially hydrolyzed guar gum (PHGG) in tube-fed children aged 1-4 years: An open-label, single-arm study.

BACKGROUND AND AIMS: Partially hydrolyzed guar gum (PHGG) is a water-soluble fiber supporting digestive health with well-established safety and efficacy. This open-label, single-arm, multicenter trial aimed to assess the tolerability and safety of a semi-elemental enteral formula containing PHGG at 12 g/L in tube-fed young children. METHODS: Children aged 1-4 years with stable conditions requiring tube feeding to provide ≥80% of their nutritional needs received the study formula for seven days. Tolerability, safety, adequacy of energy/protein intake, and weight change were assessed. RESULTS: Of 24 children (mean age 33.5 months; 10 [41.7%] female), 23 (95.8%) commenced treatment and 18 (75%) completed the study. All children had underlying neuro-developmental disabilities, often in association with gastrointestinal comorbidities requiring treatment for constipation (70.8%) or gastroesophageal reflux (66.7%). The formula was well-tolerated by 19 (82.6%) subjects, while 4 (17.4%; 95% CI: 5%, 39%) subjects withdrew early from the study due to gastrointestinal intolerance. The mean (SD) percentage energy and protein intake across the 7-day period were 103.5% (24.7) and 139.5% [50], respectively. Weight remained stable over the 7-day period (p = 0.43). The study formula was associated with a shift towards softer and more frequent stools. Pre-existing constipation was generally well controlled, and 3/16 (18.7%) subjects ceased laxatives during the study. Adverse events were reported in 12 (52%) subjects and were deemed 'probably related' or 'related' to the formula in 3 (13%) subjects. Gastrointestinal adverse events appeared more common in fiber-naïve patients (p = 0.09). CONCLUSION: The present study indicates that the study formula was safe and generally well tolerated in young tube-fed children. GOV IDENTIFIER: NCT04516213.

Olive-Derived Antioxidant Dietary Fiber Modulates Gut Microbiota Composition and Attenuates Atopic Dermatitis Like Inflammation in Mice.

SCOPE: Epidemiological data suggest that altered gut microbiota contributes to the development of atopic dermatitis (AD). The effect of an olive-derived antioxidant dietary fiber (OADF) in relieving AD symptoms in a murine model of 2,4-dinitrofluorobenzene (DNFB)-induced AD is examined and the effect of OADF in modulating host gut microbiota is explored. METHODS AND RESULTS: Mice are fed with either standard diet or standard diet + OADF for 3 weeks prior to induction of AD and maintained on the same diet throughout the DNFB application period. Dietary OADF causes significant improvement of AD-like symptoms with reduced serum levels of immunoglobulin (Ig)E, interleukin (IL)-1ß, IL-6, C-X-C motif ligand (CXCL)1, and increased serum levels of IL-10. OADF supplementation restore gut microbiota composition that are altered in AD mice. Specifically, OADF increases the proportion of intestinal bacteria (Ruminococcaceae UCG014, GCA900066575, UBA1819) associated with enhanced butyrate production, along with inhibiting Clostridiales vadin BB60 which are more prevalent in AD mice. CONCLUSION: OADF modulates gut microbiota composition, improves cytokine profile and butyrate production influencing AD-associated immune response. Results highlight the importance of the gut-skin axis for the AD dietary therapeutic agents.

Effectiveness of Partially Hydrolyzed Guar Gum in Reducing Constipation in Long Term Care Facility Residents: A Randomized Single-Blinded Placebo-Controlled Trial.

OBJECTIVES: To assess the effectiveness of partially hydrolyzed guar gum (PHGG) in improving constipation and reducing the use of laxatives among long term care facility (LTCF) residents. DESIGN: A single-center, prospective, randomized, placebo-controlled, single-blinded parallel-group trial from September 2021 to November 2021. SETTING: Four LTCF in Hong Kong. PARTICIPANTS: Fifty-two LTCF residents with chronic constipation (mean age: 83.9±7.6 years, male 38%). INTERVENTION: 5g PHGG mixed with 200ml water per day for 4 weeks was given to intervention group participants. Control group received 200ml water for 4 weeks. Participants continued their usual as-needed laxative (lactulose, senna or dulcolax) on their own initiative. MEASUREMENTS: Baseline measurements included age, gender, Charlson comorbidity index, Roackwood's Clinical Frailty Scale, body mass index and daily dietary fiber intake. Outcome measures were fecal characteristics assessed by Bristol Stool Form Scale, bowel opening frequency and laxative use frequency at baseline, first, second, third and fourth week of trial. Adverse events were measured. The study was registered on ClinicalTrial.gov; identifier: NCT05037565. RESULTS: There was no significant difference in bowel frequency and stool characteristics between the treatment group and control group. However, there was a significantly lower frequency of lactulose, senna, and total laxative use in the treatment group compared with controls in the third and fourth week. There was no significant difference in adverse effects between the two groups. CONCLUSION: This study showed that daily dietary fibre supplementation by using PHGG for 4 weeks in LTCF residents results in significantly less laxative use than placebo. It may be an effective way to reduce laxative dependence among older people living in LTCFs.

Current evidence on the therapeutic use of fiber in irritable bowel syndrome.

INTRODUCTION: Patients with irritable bowel syndrome (IBS) frequently resort to natural products, or request doctors to prescribe them, to relieve their symptoms, due to the poor efficacy and tolerability of several traditional drugs. Products containing fiber are among the most used and their clinical efficacy is discussed here based on the most recent scientific evidence. AREAS COVERED: A literature search was carried out to identify the most significant publications in order to deal with the topics of the general characteristics of fibers and the scientific evidence underlying their therapeutic use, the properties of ispaghula husk and the mechanisms by which this product carries out its therapeutic actions. EXPERT OPINION: The most recent clinical guidelines on the management of IBS consider ispaghula husk, a product containing soluble fiber, as a reasonable first line therapy for IBS patients with symptoms. In contrast, products containing insoluble fibers, particularly wheat bran, do not appear to be useful in treating IBS symptoms. The clinical data on the use of prebiotics in IBS are still inconclusive. However, low daily amounts of fructo-oligosaccharides or ß-galacto-oligosaccharides (also known as trans-galacto-oligosaccharides) may be effective in improving IBS symptoms; further trials are needed to definitively establish their clinical usefulness.

Therapeutic effect of Moringa oleifera leaves on constipation mice based on pharmacodynamics and serum metabonomics.

ETHNOPHARMACOLOGICAL RELEVANCE: Moringa oleifera is native to India, and has been introduced to China in recent years. Moringa oleifera leaves (MOL), as Ayurvedic medicine, has efficacy of Pachana karma (digestive) and Virechana karma (purgative). Folium Sennae (FS), Rhubarb (RB), Aloe vera (AV), Hemp seed (HS) are commonly used as laxatives in Traditional Chinese Medicine (TCM), which have different characteristics. However, the intensity of the diarrheal effect of MOL and its mechanism of action are unclear. AIM OF THE STUDY: The methods of pharmacology and omics were used to compare the purgative effects of MOL and FS, RB, AV, HS, and their effects on metabolomics, to analyze the purgative characteristics and related mechanisms of MOL. MATERIALS AND METHODS: C57BL/6J mouse model of constipation was established by feeding low-fiber food. Feces parameters and colon pathology were used to evaluate the effect of FS, RB, AV, HS and MOL. And mass spectrometry-based serum metabolomics was performed. The differential metabolites of these herbs in the treatment of constipation were obtained by OPLS-DA analysis. Furthermore, pathway analysis was conducted based on different metabolites. RESULTS: Moringa leaves can adjust the stool number, wet fecal weight and fecal water content to varying degrees to achieve laxative effects, and recover colon muscle thickness and mucus. Analysis of metabolomics results showed that 71 metabolites from LC-MS datasets between model group and control group were obtained. 29, 12, 44, 29 and 20 metabolites were significantly reversed by FS, RB, AV, HS, MOL compared with model group respectively. According to the metabolic pathways, RB and AV may be clustered into a similar category, and MOL, FS and HS showed similarity of metabolic characteristics. CONCLUSION: The purgative effect of MOL is inferior to that of FS, and stronger than that of AV, RB and HS. The metabolic pathway for constipation is more similar to that of FS. MOL has a long-lasting and mild effect of laxative, increasing defecation volume and water content of feces, and may become a fewer side effects medicine to treat constipation.

Novel Models for Chronic Intestinal Inflammation in Chickens: Intestinal Inflammation Pattern and Biomarkers.

For poultry producers, chronic low-grade intestinal inflammation has a negative impact on productivity by impairing nutrient absorption and allocation of nutrients for growth. Understanding the triggers of chronic intestinal inflammation and developing a non-invasive measurement is crucial to managing gut health in poultry. In this study, we developed two novel models of low-grade chronic intestinal inflammation in broiler chickens: a chemical model using dextran sodium sulfate (DSS) and a dietary model using a high non-starch polysaccharide diet (NSP). Further, we evaluated the potential of several proteins as biomarkers of gut inflammation. For these experiments, the chemical induction of inflammation consisted of two 5-day cycles of oral gavage of either 0.25mg DSS/ml or 0.35mg DSS/ml; whereas the NSP diet (30% rice bran) was fed throughout the experiment. At four times (14, 22, 28 and 36-d post-hatch), necropsies were performed to collect intestinal samples for histology, and feces and serum for biomarkers quantification. Neither DSS nor NSP treatments affected feed intake or livability. NSP-fed birds exhibited intestinal inflammation through 14-d, which stabilized by 36-d. On the other hand, the cyclic DSS-treatment produced inflammation throughout the entire experimental period. Histological examination of the intestine revealed that the inflammation induced by both models exhibited similar spatial and temporal patterns with the duodenum and jejunum affected early (at 14-d) whereas the ileum was compromised by 28-d. Calprotectin (CALP) was the only serum protein found to be increased due to inflammation. However, fecal CALP and Lipocalin-2 (LCN-2) concentrations were significantly greater in the induced inflammation groups at 28-d. This experiment demonstrated for the first time, two in vivo models of chronic gut inflammation in chickens, a DSS and a nutritional NSP protocols. Based on these models we observed that intestinal inflammation begins in the upper segments of small intestine and moved to the lower region over time. In the searching for a fecal biomarker for intestinal inflammation, LCN-2 showed promising results. More importantly, calprotectin has a great potential as a novel biomarker for poultry measured both in serum and feces.

Dietary Fiber Drives IL-1ß-Dependent Peritonitis Induced by Bacteroides fragilis via Activation of the NLRP3 Inflammasome.

Intestinal barrier is essential for dietary products and microbiota compartmentalization and therefore gut homeostasis. When this barrier is broken, cecal content overflows into the peritoneal cavity, leading to local and systemic robust inflammatory response, characterizing peritonitis and sepsis. It has been shown that IL-1ß contributes with inflammatory storm during peritonitis and sepsis and its inhibition has beneficial effects to the host. Therefore, we investigated the mechanisms underlying IL-1ß secretion using a widely adopted murine model of experimental peritonitis. The combined injection of sterile cecal content (SCC) and the gut commensal bacteria Bacteroides fragilis leads to IL-1ß-dependent peritonitis, which was mitigated in mice deficient in NLRP3 (nucleotide-binding domain, leucine-rich-containing family, pyrin domain-containing-3) inflammasome components. Typically acting as a damage signal, SCC, but not B. fragilis, activates canonical pathway of NLRP3 promoting IL-1ß secretion in vitro and in vivo. Strikingly, absence of fiber in the SCC drastically reduces IL-1ß production, whereas high-fiber SCC conversely increases this response in an NLRP3-dependent manner. In addition, NLRP3 was also required for IL-1ß production induced by purified dietary fiber in primed macrophages. Extending to the in vivo context, IL-1ß-dependent peritonitis was worsened in mice injected with B. fragilis and high-fiber SCC, whereas zero-fiber SCC ameliorates the pathology. Corroborating with the proinflammatory role of dietary fiber, IL-1R-deficient mice were protected from peritonitis induced by B. fragilis and particulate bran. Overall, our study highlights a function, previously unknown, for dietary fibers in fueling peritonitis through NLRP3 activation and IL-1ß secretion outside the gut.

Genetically determined SCFA concentration modifies the association of dietary fiber intake with changes in bone mineral density during weight loss: The Preventing Overweight Using Novel Dietary Strategies (POUNDS LOST) trial.

BACKGROUND: SCFAs are involved in regulation of body weight and bone health. OBJECTIVES: We aimed to examine whether genetic variations related to butyrate modified the relation between dietary fiber intake and changes in bone mineral density (BMD) in response to weight-loss dietary interventions. METHODS: In the 2-y Preventing Overweight Using Novel Dietary Strategies trial, 424 participants with BMD measured by DXA scan were randomly assigned to 1 of 4 diets varying in macronutrient intakes. A polygenic score (PGS) was calculated based on 7 genetic variants related to the production of butyrate for 370 of the 424 participants. RESULTS: SCFA PGS significantly modified the association between baseline dietary fiber intake and sex on 2-y changes in whole-body BMD (P-interaction = 0.049 and 0.008). In participants with the highest tertile of SCFA PGS, higher dietary fiber intake was related to a greater increase in BMD (ß:  0.0022; 95% CI: 0.0009, 0.0035; P = 0.002), whereas no such association was found for participants in the lower tertiles. In the lowest tertiles of SCFA PGS, men showed a significant increase in whole-body BMD (ß: 0.0280; 95% CI: 0.0112, 0.0447; P = 0.002) compared with women. In the highest tertile, no significant difference was found for the change in BMD between men and women. CONCLUSIONS: Our data indicate that genetic variants related to butyrate modify the relations of dietary fiber intake and sex with long-term changes in BMD in response to weight-loss diet interventions.

Friend or foe? The roles of inulin-type fructans.

Inulin-type fructans (ITFs) as functional fructans and soluble dietary fiber are a mixture of inulin, oligofructose and fructooligosaccharide with ß configuration. They are modified by gut microbiota at the end of ileum, subsequently, improve digestive system, metabolic syndrome, immune system and inflammatory diseases, and prevent against infection and cancer. However, it has been reported that inadequate consumption of ITFs aggravates the development of non-alcoholic fatty liver disease, results in gastrointestinal symptoms, liver cancer and intestinal inflammation. Therefore, this review summarizes the health benefits, pharmaceutical applications and safety evaluation of ITFs, which would direct their rational applications.

Daily intake of macronutrients and energy in childhood and its association with cardiometabolic risk factors in Colombians.

OBJECTIVES: Determine the intake and percentage of adequacy of macronutrients and their association with cardiovascular risk factors in a sample of Colombian schoolchildren. METHODS: Cross-sectional study nested in a prospective population-based cohort in schoolchildren between 6 and 10 years of age; cardiovascular risk markers and anthropometric measures were measured. Macronutrient intake was established through a food consumption frequency questionnaire (FFQ). The percentage of adequacy was evaluated by comparison with the dietary reference intakes (DRI) and the recommendations for energy and nutrient intake (RIEN) for the Colombian population. Linear regression analysis was performed to assess the association between daily macronutrient/energy intake and cardiometabolic risk factors. RESULTS: A total of 1,282 school children (51.09% boys and 48.91% girls; mean age 8.4 ± 1.4 years). The percentage of energy adequacy was 107% (Q1=87.5; Q3=127.2). The macronutrients in overadequacy were proteins and carbohydrates. The total fiber had a low adequacy around 26.0% (Q1=15.8; Q3=38.6). Fat intake was positively associated with BMI, insulin, and HOMA-IR index, while carbohydrate consumption was related to these same factors, although negatively in tight models. CONCLUSIONS: Schoolchildren in this study had an inadequate protein, carbohydrate, and fiber intake. The results suggest a significant positive and negative relationship between the consumption of both fat and carbohydrates and cardiometabolic risk factors such as BMI, insulin levels, and HOMA-IR.

Multiple dietary fiber for gestational hyperinsulinism: A protocol of systematic review and meta-analysis of randomized clinical trials.

INTRODUCTION: Gestational hyperinsulinism is a metabolic disease which is widely concerned at home and abroad. It is a clinical consensus that the embryo implantation ability of patients with hyperinsulinemia is decreased and the abortion rate after implantation is high. The treatment of gestational hyperinsulinism with Multiple dietary fiber diets has been proven. However, due to the lack of evidence, there is no specific method or recommendation, it is necessary to carry out a systematic evaluation of Multiple dietary fiber diet, to provide effective evidence for further research. METHODS AND ANALYSIS: The following databases will be searched from their inception to August 2020: Electronic database includes PubMed, Embase, Cochrane Library, Web of Science, Nature, Science online, Chinese Biomedical Database WanFang, VIP medicine information, and CNKI. Primary outcomes: Fasting glucose, fasting insulin, homeostasis model assessment of insulin resistance, glycosylated hemoglobin. Additional outcomes: Low Density Lipoprotein (LDL), High Density Lipoprotein (HDL), triglycerides (TG), total serum cholesterol (TC). Data will be extracted by 2 researchers independently, risk of bias of the meta-analysis will be evaluated based on the Cochrane Handbook for Systematic Reviews (SR) of Interventions. All data analysis will be conducted by data statistics software Review Manager V.5.3. and Stata V.12.0. RESULTS: The results of this study will systematically evaluate the effectiveness and safety of Multiple dietary fiber diet interventions in the treatment of gestational hyperinsulinism. CONCLUSION: The SR of this study will summarize the current published evidence of Multiple dietary fiber for the treatment of gestational hyperinsulinism, which can further guide the promotion and application of it. ETHICS AND DISSEMINATION: This study is a SR, the outcomes are based on the published evidence, so examination and agreement by the ethics committee are not required in this study. We intend to publish the study results in a journal or conference presentations. OPEN SCIENCE FRA NETWORK (OSF) REGISTRATION NUMBER: August 19, 2020. osf.io/tbc7z. (https://osf.io/tbc7z).

Inflammatory Bowel Disease: Are Symptoms and Diet Linked?

New Zealand (NZ) has one of the world's highest incidence rates of Inflammatory Bowel Disease (IBD), a group of chronic inflammatory conditions that affect the gastrointestinal tract. Patients with IBD often believe certain foods influence their disease symptoms and consequently may alter their diet considerably. The objective of this study was to determine foods, additives, and cooking methods (dietary elements) that NZ IBD patients identify in the onset, exacerbation, or reduction of their symptoms. A total of 233 participants completed a self-administered questionnaire concerning symptom behaviour in association with 142 dietary elements. Symptom onset and symptom exacerbation were associated with dietary elements by 55% (128) and 70% (164) of all IBD participants, respectively. Fruit and vegetables were most frequently identified, with dairy products, gluten-containing bread, and foods with a high fat content also considered deleterious. Of all IBD participants, 35% (82) associated symptom reduction with dietary elements. The identified foods were typically low in fibre, saturated fatty acids, and easily digestible. No statistically significant differences were seen between the type or number of dietary elements and disease subtype or recent disease activity. The association between diet and symptoms in patients with IBD and the mechanism(s) involved warrant further research and may lead to the development of IBD specific dietary guidelines.

Interventions for preventing postpartum constipation.

BACKGROUND: Postpartum constipation, with symptoms, such as pain or discomfort, straining, and hard stool, is a common condition affecting mothers. Haemorrhoids, pain at the episiotomy site, effects of pregnancy hormones, and haematinics used in pregnancy can increase the risk of postpartum constipation. Eating a high-fibre diet and increasing fluid intake are usually encouraged. Although laxatives are commonly used in relieving constipation, the effectiveness and safety of available interventions for preventing postpartum constipation should be ascertained. This is an update of a review first published in 2015. OBJECTIVES: To evaluate the effectiveness and safety of interventions for preventing postpartum constipation. SEARCH METHODS: We searched Cochrane Pregnancy and Childbirth's Trials Register, and two trials registers ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform (ICTRP) (7 October 2019), and screened reference lists of retrieved trials. SELECTION CRITERIA: We considered all randomised controlled trials (RCTs) comparing any intervention for preventing postpartum constipation versus another intervention, placebo, or no intervention in postpartum women. Interventions could include pharmacological (e.g. laxatives) and non-pharmacological interventions (e.g. acupuncture, educational and behavioural interventions). Quasi-randomised trials and cluster-RCTs were eligible for inclusion; none were identified. Trials using a cross-over design were not eligible. DATA COLLECTION AND ANALYSIS: Two review authors independently screened the results of the search to select potentially relevant trials, extracted data, assessed risk of bias, and the certainty of the evidence, using the GRADE approach. We did not pool results in a meta-analysis, but reported them per study. MAIN RESULTS: We included five trials (1208 postpartum mothers); three RCTs and two quasi-RCTs. Four trials compared a laxative with placebo; one compared a laxative plus a bulking agent versus the same laxative alone, in women who underwent surgical repair of third degree perineal tears. Trials were poorly reported, and four of the five trials were published over 40 years ago. We judged the risk of bias to be unclear for most domains. Overall, we found a high risk of selection and attrition bias. Laxative versus placebo We included four trials in this comparison. Two of the trials examined the effects of laxatives that are no longer used; one has been found to have carcinogenic properties (Danthron), and the other is not recommended for lactating women (Bisoxatin acetate); therefore, we did not include their results in our main findings. None of the trials included in this comparison assessed our primary outcomes: pain or straining on defecation, incidence of postpartum constipation, or quality of life; or many of our secondary outcomes. A laxative (senna) may increase the number of women having their first bowel movement within 24 hours after delivery (risk ratio (RR) 2.90, 95% confidence interval (CI) 2.24 to 3.75; 1 trial, 471 women; low-certainty evidence); may have little or no effect on the number of women having their first bowel movement on day one after delivery (RR 0.94, 95% CI 0.72 to 1.22; 1 trial, 471 women; very low-certainty evidence); may reduce the number of women having their first bowel movement on day two (RR 0.23, 95% CI 0.11 to 0.45; 1 trial, 471 women; low-certainty evidence); and day three (RR 0.05, 95% CI 0.00 to 0.89; 1 trial, 471 women; low-certainty evidence); and may have little or no effect on the number of women having their first bowel movement on day four after delivery (RR 0.22, 95% CI 0.03 to 1.87; 1 trial, 471 women; very low-certainty evidence), but some of the evidence is very uncertain. Adverse effects were poorly reported. Low-certainty evidence suggests that the laxative (senna) may increase the number of women experiencing abdominal cramps (RR 4.23, 95% CI 1.75 to 10.19; 1 trial, 471 women). Very low-certainty evidence suggests that laxatives taken by the mother may have little or no effect on loose stools in the baby (RR 0.62, 95% CI 0.16 to 2.41; 1 trial, 281 babies); or diarrhoea (RR 2.46, 95% CI 0.23 to 26.82; 1 trial, 281 babies). Laxative plus bulking agent versus laxative only Very low-certainty evidence from one trial (147 women) suggests no evidence of a difference between these two groups of women who underwent surgical repair of third degree perineal tears; only median and range data were reported. The trial also reported no evidence of a difference in the incidence of postpartum constipation (data not reported), but did not report on quality of life. Time to first bowel movement was reported as a median (range); very low-certainty evidence suggests little or no difference between the two groups. A laxative plus bulking agent may increase the number of women having any episode of faecal incontinence during the first 10 days postpartum (RR 1.81, 95% CI 1.01 to 3.23; 1 trial, 147 women; very low-certainty evidence). The trial did not report on adverse effects of the intervention on babies, or many of our secondary outcomes. AUTHORS' CONCLUSIONS: There is insufficient evidence to make general conclusions about the effectiveness and safety of laxatives for preventing postpartum constipation. The evidence in this review was assessed as low to very low-certainty evidence, with downgrading decisions based on limitations in study design, indirectness and imprecision. We did not identify any trials assessing educational or behavioural interventions. We identified four trials that examined laxatives versus placebo, and one that examined laxatives versus laxatives plus stool bulking agents. Further, rigorous trials are needed to assess the effectiveness and safety of laxatives during the postpartum period for preventing constipation. Trials should assess educational and behavioural interventions, and positions that enhance defecation. They should report on the primary outcomes from this review: pain or straining on defecation, incidence of postpartum constipation, quality of life, time to first bowel movement after delivery, and adverse effects caused by the intervention, such as: nausea or vomiting, pain, and flatus.

Does Fibre-fix provided to people with irritable bowel syndrome who are consuming a low FODMAP diet improve their gut health, gut microbiome, sleep and mental health? A double-blinded, randomised controlled trial.

INTRODUCTION: A diet low in fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAP) is an effective way to reduce gut symptoms in people with irritable bowel syndrome (IBS). This diet reduces the intake of fermentable fibres, leading to changes of the gut microbiota and insufficient fermentation in the large bowel, resulting in reduced production of short-chain fatty acids (SCFAs), such as butyrate, which has unfavourable implications for gut health, sleep and mental health. This study will examine the effect of Fibre-fix, a supplement containing a mix of dietary fibres, on the human gut microbiome composition, fermentative capacity, sleep, quality of life (QOL) and mental health of people with IBS who consume a low FODMAP diet (LFD). METHODS AND ANALYSIS: A randomised, double-blind, placebo-controlled, study design is proposed to examine whether Fibre-fix added to an existing LFD may help modulate gastrointestinal function, improve markers of sleep, mental health and promote QOL in patients with IBS. Participants will provide stool and blood samples, daily bowel symptoms diaries and 3-day diet records. Additionally, they will complete validated questionnaires relating to FODMAP intake, sleep, mental health and QOL before and after a 3-week intervention. Gut health will be assessed via faecal microbiome composition, faecal pH and SCFA levels. Alteration of sleep will be recorded using an actigraphy device worn by all participants over the whole study. Multivariate analysis will be used to examine the gut microbiome and repeated measures Analysis of variance (ANOVA) will be used for dependent variables from questionnaires related to bowel symptoms, stool type, sleep, mental health and QOL to assess the differences between intervention and control groups after adjustment for confounding variables. ETHICS AND DISSEMINATION: Ethics approval was obtained from the Human Research Ethics Committee of Edith Cowan University (2019-00619-YAN). Results will be disseminated in peer-review journal publications, and conference presentations. Participants will be provided with a summary of findings once the study is completed. If Fibre-fix is shown to result in favourable changes in gut microbial composition, SCFA production, sleep and mental well-being without exacerbating symptoms, this will provide additional dietary management options for those with IBS following an LFD. TRIAL REGISTRATION NUMBER: ACTRN12620000032954.

Dietary fibre and whole grains in diabetes management: Systematic review and meta-analyses.

BACKGROUND: Fibre is promoted as part of a healthy dietary pattern and in diabetes management. We have considered the role of high-fibre diets on mortality and increasing fibre intake on glycaemic control and other cardiometabolic risk factors of adults with prediabetes or diabetes. METHODS AND FINDINGS: We conducted a systematic review of published literature to identify prospective studies or controlled trials that have examined the effects of a higher fibre intake without additional dietary or other lifestyle modification in adults with prediabetes, gestational diabetes, type 1 diabetes, and type 2 diabetes. Meta-analyses were undertaken to determine the effects of higher fibre intake on all-cause and cardiovascular mortality and increasing fibre intake on glycaemic control and a range of cardiometabolic risk factors. For trials, meta regression analyses identified further variables that influenced the pooled findings. Dose response testing was undertaken; Grading of Recommendations Assessment, Development and Evaluation (GRADE) protocols were followed to assess the quality of evidence. Two multicountry cohorts of 8,300 adults with type 1 or type 2 diabetes followed on average for 8.8 years and 42 trials including 1,789 adults with prediabetes, type 1, or type 2 diabetes were identified. Prospective cohort data indicate an absolute reduction of 14 fewer deaths (95% confidence interval (CI) 4-19) per 1,000 participants over the study duration, when comparing a daily dietary fibre intake of 35 g with the average intake of 19 g, with a clear dose response relationship apparent. Increased fibre intakes reduced glycated haemoglobin (HbA1c; mean difference [MD] -2.00 mmol/mol, 95% CI -3.30 to -0.71 from 33 trials), fasting plasma glucose (MD -0.56 mmol/L, 95% CI -0.73 to -0.38 from 34 trials), insulin (standardised mean difference [SMD] -2.03, 95% CI -2.92 to -1.13 from 19 trials), homeostatic model assessment of insulin resistance (HOMA IR; MD -1.24 mg/dL, 95% CI -1.72 to -0.76 from 9 trials), total cholesterol (MD -0.34 mmol/L, 95% CI -0.46 to -0.22 from 27 trials), low-density lipoprotein (LDL) cholesterol (MD -0.17 mmol/L, 95% CI -0.27 to -0.08 from 21 trials), triglycerides (MD -0.16 mmol/L, 95% CI -0.23 to -0.09 from 28 trials), body weight (MD -0.56 kg, 95% CI -0.98 to -0.13 from 18 trials), Body Mass Index (BMI; MD -0.36, 95% CI -0·55 to -0·16 from 14 trials), and C-reactive protein (SMD -2.80, 95% CI -4.52 to -1.09 from 7 trials) when compared with lower fibre diets. All trial analyses were subject to high heterogeneity. Key variables beyond increasing fibre intake were the fibre intake at baseline, the global region where the trials were conducted, and participant inclusion criteria other than diabetes type. Potential limitations were the lack of prospective cohort data in non-European countries and the lack of long-term (12 months or greater) controlled trials of increasing fibre intakes in adults with diabetes. CONCLUSIONS: Higher-fibre diets are an important component of diabetes management, resulting in improvements in measures of glycaemic control, blood lipids, body weight, and inflammation, as well as a reduction in premature mortality. These benefits were not confined to any fibre type or to any type of diabetes and were apparent across the range of intakes, although greater improvements in glycaemic control were observed for those moving from low to moderate or high intakes. Based on these findings, increasing daily fibre intake by 15 g or to 35 g might be a reasonable target that would be expected to reduce risk of premature mortality in adults with diabetes.