{ "slug": "why-is-my-poop-so-long", "question": "Why is my poop so long?", "shortTitle": "Why Is My Poop So Long?", "clinicalQuestion": "In healthy adults, what determines stool length and shape (e.g., fiber intake, colonic transit time), and does a long stool indicate normal variation versus an underlying bowel problem?", "pico": { "population": "Healthy adults passing a bowel movement that appears unusually long", "intervention": "Observed long stool length/shape", "comparator": "Average or typical stool length (Bristol stool scale types 3-4)", "outcomes": [ "Stool length and diameter measurements", "Bristol stool form scale score", "Colonic transit time", "Dietary fiber intake", "Association with bowel pathology (e.g., stricture, mass) on follow-up" ] }, "category": "bowel-function", "relatedConditions": [ "bowel-function", "constipation", "irritable-bowel-syndrome" ], "relatedTreatments": [], "relatedEvidence": [], "bottomLine": { "verdict": "No study has directly looked at why healthy people's stools are long, or whether a long stool means something is wrong.", "detail": "The 34 studies found are almost all trials of constipation treatments, or lab and microbiome studies; none set out to measure stool length itself. Related measures such as stool thickness, consistency, weight, and transit time have been studied — for example, more fibre softened stool, increased fecal weight, and shortened transit time in people without bowel dysfunction, and a small smart-toilet study linked slower stool passage to thicker stool — but no study has tested whether these relate to stool length, or whether a long stool signals an underlying bowel problem such as a stricture or mass.", "studyIds": [ "pmid:41611088", "pmid:40349171", "pmid:41748755", "pmid:41193362" ] }, "strength": { "level": "very-low", "why": "The 30 human studies found measure a related question rather than this one, so they can only be read indirectly.", "override": null }, "direction": { "level": "not-studied", "why": "No study has measured this outcome in people with this condition.", "override": null }, "counts": { "recordsRetrieved": 1060, "recordsScreened": 199, "included": 34, "rcts": 13, "systematicReviews": 3, "observational": 10, "participants": 20984, "yearFrom": 2023, "yearTo": 2026, "registeredTrialsWithoutResults": 24 }, "excluded": [], "outcomes": [ { "name": "Stool length and diameter measurements", "status": "not-studied", "note": "No study in this set measured stool length or diameter as an outcome. One very small smart-toilet study tracked stool thickness and how long it took to drop, but not length, and only in 11 people.", "studyIds": [ "pmid:40349171" ] }, { "name": "Bristol stool form scale score", "status": "insufficient", "note": "Many trials measured the Bristol scale, which grades stool texture from hard lumps to watery — not length. These trials were done in people with constipation or IBS, not in people asking why a stool was long, so they cannot answer this question directly.", "studyIds": [ "pmid:42186252", "pmid:42030329", "pmid:41980711", "pmid:41327986", "pmid:41193362", "pmid:41047557", "pmid:40780410", "pmid:40349171", "pmid:39697209", "pmid:39032787", "pmid:38470623", "pmid:37793306" ] }, { "name": "Dietary fiber intake", "status": "possible-improvement", "note": "In people with normal bowel function, more fibre was linked to softer stool, more stool weight, and faster transit; a high-fibre diet was linked to better stool form in a small group of healthy women. Neither study measured stool length.", "studyIds": [ "pmid:41611088", "pmid:40312033" ] }, { "name": "Association with bowel pathology (e.g., stricture, mass)", "status": "not-studied", "note": "One small surgical case series looked at outcomes after surgery for anal narrowing (stenosis) that developed following hemorrhoid surgery — it did not test whether stool length predicts strictures or masses in otherwise healthy people. A separate study found that the Bristol Stool Scale (a stool-shape tool) was poor at identifying constipation in children, while a different constipation-symptom score was much more accurate; neither tested stool length as a predictor of structural bowel disease. No study has tested whether a long stool in an otherwise healthy person predicts a stricture, mass, or other bowel problem.", "studyIds": [ "pmid:41748755", "pmid:41193362" ] } ], "benefits": [ { "text": "In people with normal bowel function, higher fibre intake was linked to softer stool, more stool weight, more frequent bowel movements, and faster gut transit — though this evidence is based on statistical models across many measurements, not a head-to-head trial of long stools specifically.", "studyIds": [ "pmid:41611088" ] }, { "text": "A small pilot study found that healthy women following a traditional high-fibre diet had better stool form than those on their usual diet after four weeks.", "studyIds": [ "pmid:40312033" ] } ], "limitations": [ { "text": "Almost every study here was designed to test treatments for constipation or to study gut bacteria — none asked 'why is a stool long' or compared long stools with other lengths.", "studyIds": [ "pmid:42553215", "pmid:42186252", "pmid:42128431", "pmid:42030329", "pmid:41980711", "pmid:41327986", "pmid:41180988", "pmid:41034384", "pmid:40780410", "pmid:39697209", "pmid:39064725", "pmid:39051756", "pmid:38829940", "pmid:38464992", "pmid:38455871", "pmid:37793306" ] }, { "text": "The standard tool used in these studies, the Bristol stool form scale, grades texture (hard to watery) on a 1–7 scale. It does not measure length, and one study found it was a poor tool even for diagnosing constipation.", "studyIds": [ "pmid:41193362" ] }, { "text": "The one study that measured stool size directly used a smart toilet with only 11 participants and no control for diet or hydration, so it cannot be generalised.", "studyIds": [ "pmid:40349171" ] }, { "text": "Evidence on bowel narrowing and stool shape comes only from people who had already had surgery for a known problem, not from otherwise healthy people with a long stool.", "studyIds": [ "pmid:41748755" ] } ], "risks": [ { "text": "In a small surgical case series, people with an anal narrowing after hemorrhoid surgery had thin stool as a symptom, and most needed a procedure to fix it. This describes people with an already-diagnosed narrowing — it does not show that a long or thin stool in a healthy person signals this problem.", "studyIds": [ "pmid:41748755" ], "severity": "serious" }, { "text": "Harder stool took more pressure and time to pass in a lab study using artificial stool in healthy volunteers, which may make passing a large or firm stool uncomfortable.", "studyIds": [ "pmid:38533644" ], "severity": "minor" } ], "whyPeopleTryIt": [ { "text": "Noticing a stool that looks unusually long or different than usual naturally makes people wonder if their diet, hydration, or gut is working differently." }, { "text": "Online health content and toilet folklore often links stool shape and size to gut health, prompting people to search for reassurance." }, { "text": "People who have recently changed their diet, started a supplement, or eaten more fibre may notice a change in stool size and want to know if that's the cause." }, { "text": "Concern about serious bowel disease, especially after hearing that 'thin stool can be a warning sign,' drives many people to check whether their own stool is a cause for concern." } ], "keyStudies": [ "pmid:40349171", "pmid:41611088", "pmid:38533644", "pmid:37926855", "pmid:41180988", "pmid:41748755", "pmid:41193362" ], "studies": [ { "id": "pmid:42553215", "pmid": "42553215", "doi": "10.3389/fneur.2026.1843563", "nctId": null, "pmcid": "PMC13433532", "title": "Clinical efficacy of repetitive transcranial magnetic stimulation combined with electroacupuncture at Baliao points for functional constipation: a retrospective study", "firstAuthor": "Gao", "multipleAuthors": true, "journal": "Front Neurol", "year": 2026, "design": "retrospective", "n": 142, "nField": "reported", "population": "Adults with functional constipation treated at one hospital", "intervention": "Transcranial magnetic stimulation combined with electroacupuncture at Baliao points", "comparator": "Electroacupuncture alone", "primaryOutcome": "Weekly number of complete bowel movements", "result": "After 8 weeks, bowel movements increased more with combined therapy than with acupuncture alone (median 4 vs 3 per week, p<0.001), with better symptom, quality-of-life and transit-time scores", "resultDirection": "benefit", "quality": "low", "qualityWhy": "It was a retrospective, non-randomized study without blinding or a sham control, so the findings are only exploratory.", "directness": "indirect", "limitations": "Given the absence of randomization, sham control and blinding, the findings should be interpreted as exploratory and hypothesis-generating", "followUp": "8 weeks", "plainFinding": "More bowel movements with combined therapy.", "retracted": false, "expressionOfConcern": false, "hasErratum": false, "url": "https://pubmed.ncbi.nlm.nih.gov/42553215/", "sourceText": "BACKGROUND: Functional constipation (FC) is a prevalent gastrointestinal disorder with suboptimal treatment outcomes. Using a retrospective design, we examined whether adding repetitive transcranial magnetic stimulation (rTMS) to electroacupuncture (EA) at Baliao points was associated with greater clinical improvement than EA alone in patients with FC, and to generate hypotheses regarding combined neuromodulation. METHODS: This retrospective cohort study included FC patients treated at a single hospital from February 2022 to March 2025, allocated by the treatment received to an observation group (rTMS combined with EA, n = 67) or a control group (EA alone, n = 75). The primary outcome was weekly complete spontaneous bowel movements (CSBMs); secondary outcomes were Patient Assessment of Constipation Symptoms (PAC-SYM), Patient Assessment of Constipation Quality of Life (PAC-QOL), Bristol Stool Form Scale (BSFS) and colonic transit time (CTT). Longitudinal outcomes were analyzed with linear mixed-effects models; confounding was addressed by propensity-score inverse-probability weighting, multivariable analysis of covariance and propensity-score matching; between-group effects are reported with 95% confidence intervals (CIs). RESULTS: After 8 weeks, CSBMs increased more in the observation group (week-8 median 4.00 vs. 3.00; p < 0.001), as did improvements in PAC-SYM, PAC-QOL, BSFS and CTT (all p < 0.001). Mixed-effects models showed a significant group-by-time interaction for every repeated outcome (all p < 0.001). The differences persisted after adjustment for baseline covariates (adjusted week-8 CSBM difference 0.89, 95% CI 0.65 to 1.13; PAC-SYM - 6.18, 95% CI - 6.50 to -5.85). The proportion reaching ≥3 CSBMs/week did not differ between groups (92.5% vs. 88.0%, p = 0.37), whereas a large response (an increase of ≥3 CSBMs/week from baseline) was more frequent with combined treatment (67.2% vs. 17.3%; relative risk 3.87, 95% CI 2.30 to 6.53). Adverse events were mild and comparable between groups (22.39% vs. 18.67%, p = 0.583). CONCLUSION: In this retrospective, non-randomized cohort, adding rTMS to EA at Baliao points was associated with greater improvements in bowel frequency, symptom severity, quality of life and colonic transit, with comparable safety, and these associations were robust to propensity-score and multivariable adjustment. Given the absence of randomization, sham control and blinding, the findings should be interpreted as exploratory and hypothesis-generating and require confirmation in adequately powered, sham-controlled randomized trials.", "provenance": [ { "field": "n", "quote": "observation group (rTMS combined with EA, n = 67)" }, { "field": "n", "quote": "control group (EA alone, n = 75)" }, { "field": "population", "quote": "FC patients treated at a single hospital from February 2022 to March 2025" }, { "field": "intervention", "quote": "adding repetitive transcranial magnetic stimulation (rTMS) to electroacupuncture (EA) at Baliao points" }, { "field": "comparator", "quote": "control group (EA alone, n = 75)" }, { "field": "primaryOutcome", "quote": "The primary outcome was weekly complete spontaneous bowel movements (CSBMs)" }, { "field": "result", "quote": "After 8 weeks, CSBMs increased more in the observation group (week-8 median 4.00 vs. 3.00; p < 0.001)" }, { "field": "limitations", "quote": "Given the absence of randomization, sham control and blinding, the findings should be interpreted as exploratory and hypothesis-generating" }, { "field": "followUp", "quote": "After 8 weeks" } ] }, { "id": "pmid:42186252", "pmid": "42186252", "doi": "10.1111/nmo.70354", "nctId": null, "pmcid": null, "title": "Effects of a Supervised Telerehabilitation-Based Exercise Program on Constipation Symptoms and Quality of Life in Adults With Chronic Constipation: A Randomized Controlled Trial", "firstAuthor": "Can", "multipleAuthors": true, "journal": "Neurogastroenterol Motil", "year": 2026, "design": "rct", "n": 32, "nField": "reported", "population": "adults with chronic constipation", "intervention": "supervised telerehabilitation exercise program plus online education", "comparator": "online education alone", "primaryOutcome": "stool consistency and constipation severity scores", "result": "intervention group had more normal stool form, lower constipation severity scores, and better satisfaction scores than control at 4 weeks", "resultDirection": "benefit", "quality": "low", "qualityWhy": "Very small trial of only 32 people over just 4 weeks, with the authors themselves calling the findings preliminary and needing confirmation.", "directness": "indirect", "limitations": "Small sample size, short follow-up, no objective physiological outcomes measured, authors state findings are preliminary and need confirmation in larger trials", "followUp": "4 weeks", "plainFinding": "Exercise program improved stool form, less constipation.", "retracted": false, "expressionOfConcern": false, "hasErratum": false, "url": "https://pubmed.ncbi.nlm.nih.gov/42186252/", "sourceText": "BACKGROUND: Chronic constipation is a prevalent gastrointestinal disorder associated with substantial symptom burden and impaired quality of life. Evidence supporting synchronous physiotherapist-supervised telerehabilitation in adults with chronic constipation is scarce. METHODS: Adults with chronic constipation were allocated to either a supervised telerehabilitation-based exercise plus online education group (n = 16) or an online education-only control group (n = 16). The intervention consisted of live, physiotherapist-supervised exercise sessions delivered three times per week over 4 weeks. Outcomes included stool consistency assessed by the Bristol Stool Form Scale, constipation severity assessed by the Constipation Assessment Scale (CAS) and Constipation Severity Instrument (CSI), disease-specific quality of life assessed by the Patient Assessment of Constipation Quality of Life questionnaire (PAC-QOL), and adherence. KEY RESULTS: By Week 4, normal stool form (Bristol Types 3-5) was observed in 68.8% of the intervention group and 37.5% of the control group. CAS scores were lower in the intervention group at Week 4 (3.56 ± 2.94 vs. 7.25 ± 4.33; p = 0.008). CSI total scores also favored the intervention group (24.75 ± 9.48 vs. 37.19 ± 13.84; p = 0.006), with greater percentage improvements in patient-reported obstructive defecation, colonic inertia, pain, and total severity scores. For PAC-QOL, the between-group difference was significant only for satisfaction percentage change (p = 0.008). Mean adherence was 96.9%. CONCLUSIONS AND INFERENCES: Adding synchronous physiotherapist-supervised telerehabilitation-based exercise to online education may improve stool form and patient-reported constipation severity compared with education alone. These preliminary findings require confirmation in larger trials with objective physiological outcomes and longer follow-up. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT05899062.", "provenance": [ { "field": "n", "quote": "telerehabilitation-based exercise plus online education group (n = 16) or an online education-only control group (n = 16)" }, { "field": "population", "quote": "Adults with chronic constipation" }, { "field": "intervention", "quote": "supervised telerehabilitation-based exercise plus online education group" }, { "field": "comparator", "quote": "online education-only control group" }, { "field": "primaryOutcome", "quote": "Outcomes included stool consistency assessed by the Bristol Stool Form Scale, constipation severity assessed by the Constipation Assessment Scale (CAS) and Constipation Severity Instrument (CSI)" }, { "field": "result", "quote": "By Week 4, normal stool form (Bristol Types 3-5) was observed in 68.8% of the intervention group and 37.5% of the control group. CAS scores were lower in the intervention group at Week 4 (3.56 ± 2.94 vs. 7.25 ± 4.33; p = 0.008)." } ] }, { "id": "pmid:42128431", "pmid": "42128431", "doi": "10.17761/2026-D-25-00017", "nctId": null, "pmcid": null, "title": "Exploring the Impact of Yoga on Autonomic Nervous System Function, Social Functioning, and Quality of Life in People with IBS", "firstAuthor": "Bhattacharya", "multipleAuthors": true, "journal": "Int J Yoga Therap", "year": 2026, "design": "rct", "n": 202, "nField": "reported", "population": "adults aged 18-45 with irritable bowel syndrome (IBS)", "intervention": "3-month yoga program", "comparator": "control group (no yoga)", "primaryOutcome": "autonomic nervous system function and quality of life", "result": "yoga group had reduced resting heart rate, improved heart rate variability ratio, increased Valsalva ratio, and better quality of life scores", "resultDirection": "benefit", "quality": "low", "qualityWhy": "this study measured autonomic function and quality of life, not stool characteristics like length, so it doesn't answer the question about why someone's poop is long.", "directness": "indirect", "limitations": "abstract does not mention stool form, size, or bowel habit changes specifically; focuses on autonomic and quality of life measures.", "followUp": "3 months", "plainFinding": "Not relevant to stool length.", "retracted": false, "expressionOfConcern": false, "hasErratum": false, "url": "https://pubmed.ncbi.nlm.nih.gov/42128431/", "sourceText": "As per the Rome IV criteria, a disorder of gut-brain interaction such as irritable bowel syndrome (IBS) is characterized by recurrent abdominal pain occurring at least 1 day per week for the previous 3 months and associated changes in bowel movements (defecation, stool frequency, or stool form). These symptoms must have begun at least 6 months prior to diagnosis. IBS affects 4% to 7% of the Indian population, with a higher prevalence observed in women and younger individuals. The present randomized controlled trial investigated the effects of a 3-month yoga intervention on IBS management. The study included 202 people (ages 18-45) diagnosed with IBS according to the Rome IV criteria. Participants were divided into a yoga intervention group (n = 102) and a control group (n = 100). Both groups underwent baseline and follow-up assessments to measure autonomic function and quality of life. The yoga group showed significant improvements in autonomic function, with reductions in resting heart rate (p < 0.0001) and the low- to high-frequency ratio of heart rate variability (p < 0.0001), as well as an increase in the Valsalva ratio (p = 0.0100). Additionally, this group experienced notable improvements in their quality of life as measured by the IBS-QOL score. Our findings suggest that yoga could be a valuable complementary therapy for IBS by enhancing autonomic regulation and improving overall well-being.", "provenance": [ { "field": "population", "quote": "The study included 202 people (ages 18-45) diagnosed with IBS according to the Rome IV criteria." }, { "field": "intervention", "quote": "a 3-month yoga intervention on IBS management" }, { "field": "comparator", "quote": "control group (n = 100)" }, { "field": "primaryOutcome", "quote": "to measure autonomic function and quality of life" }, { "field": "result", "quote": "The yoga group showed significant improvements in autonomic function, with reductions in resting heart rate (p < 0.0001) and the low- to high-frequency ratio of heart rate variability (p < 0.0001), as well as an increase in the Valsalva ratio (p = 0.0100)." }, { "field": "n", "quote": "The study included 202 people" } ] }, { "id": "pmid:42030329", "pmid": "42030329", "doi": "10.1371/journal.pone.0337019", "nctId": null, "pmcid": "PMC13108732", "title": "Effects of a spore-forming probiotic blend on bowel habits and physical well-being in adults with functional constipation: A randomized, double-blind, placebo-controlled trial", "firstAuthor": "Park", "multipleAuthors": true, "journal": "PLoS One", "year": 2026, "design": "rct", "n": 78, "nField": "reported", "population": "adults with functional constipation", "intervention": "spore-forming probiotic blend (Clostridium butyricum, Weizmannia coagulans, Bacillus subtilis)", "comparator": "placebo", "primaryOutcome": "changes in weekly bowel movements and stool form", "result": "probiotic group had significant improvements in bowel symptoms and shifted stool consistency toward normal types", "resultDirection": "benefit", "quality": "moderate", "qualityWhy": "it was a randomized double-blind placebo-controlled trial but with a small sample size and only 4 weeks of follow-up", "directness": "indirect", "limitations": "abstract does not mention limitations such as small sample size or short duration explicitly, though the study design has these inherent constraints", "followUp": "4 weeks", "plainFinding": "Probiotic eased constipation symptoms.", "retracted": false, "expressionOfConcern": false, "hasErratum": false, "url": "https://pubmed.ncbi.nlm.nih.gov/42030329/", "sourceText": "We aimed to evaluate the efficacy and safety of a spore-forming probiotic blend containing Clostridium butyricum IDCC 1301, Weizmannia coagulans IDCC 1201, and Bacillus subtilis IDCC 1101 for improving bowel function and well-being in adults with functional constipation (FC). In a randomized, double-blind, placebo-controlled trial, 78 adults with FC (Rome IV criteria) received either probiotic blend (n = 40) or placebo (n = 38) daily for 4 weeks. Primary outcomes were changes in weekly spontaneous bowel movements (WSBM) and stool form. Secondary outcomes included physical functioning scores from the 36-Item Short Form Health Survey. The probiotic blend group showed significant improvements in irritant bowel movements (p = 0.0458), incomplete evacuation (p = 0.0374), and abdominal pain before defecation (p = 0.0090). Stool consistency shifted toward normal types (Bristol types 3-4, p = 0.0176). Physical functioning improved only in the probiotic blend group (p = 0.0300). Probiotic blend effectively alleviated symptoms of FC and improved physical well-being. Trial registration: Clinical Research Information Service (CRIS), KCT0010085.", "provenance": [ { "field": "n", "quote": "78 adults with FC (Rome IV criteria) received either probiotic blend (n = 40) or placebo (n = 38)" }, { "field": "population", "quote": "adults with functional constipation (FC)" }, { "field": "intervention", "quote": "spore-forming probiotic blend containing Clostridium butyricum IDCC 1301, Weizmannia coagulans IDCC 1201, and Bacillus subtilis IDCC 1101" }, { "field": "comparator", "quote": "In a randomized, double-blind, placebo-controlled trial, 78 adults with FC (Rome IV criteria) received either probiotic blend (n = 40) or placebo (n = 38) daily for 4 weeks." }, { "field": "primaryOutcome", "quote": "Primary outcomes were changes in weekly spontaneous bowel movements (WSBM) and stool form." }, { "field": "result", "quote": "The probiotic blend group showed significant improvements in irritant bowel movements (p = 0.0458), incomplete evacuation (p = 0.0374), and abdominal pain before defecation (p = 0.0090). Stool consistency shifted toward normal types (Bristol types 3-4, p = 0.0176)." } ] }, { "id": "pmid:41980711", "pmid": "41980711", "doi": "10.1163/18762891-bja00116", "nctId": null, "pmcid": null, "title": "Effects of fermented milk containing Lacticaseibacillus paracasei strain Shirota on constipation and gut microbiota: A randomised pilot study in Vietnam", "firstAuthor": "Hoang Van", "multipleAuthors": true, "journal": "Benef Microbes", "year": 2026, "design": "rct", "n": 51, "nField": "reported", "population": "Vietnamese adults with constipation and hard or lumpy stools", "intervention": "fermented milk with Lacticaseibacillus paracasei strain Shirota probiotic, one bottle daily for 4 weeks", "comparator": "no intervention (control group)", "primaryOutcome": "proportion of participants with hard or lumpy stools in 25% or more of bowel movements over 4 weeks", "result": "Probiotic group had significantly fewer hard/lumpy stools, more frequent stools, and less constipation on questionnaire scores compared to control", "resultDirection": "benefit", "quality": "low", "qualityWhy": "This was a small, open-label pilot study without a placebo or blinding, so bias and small numbers limit confidence in the results.", "directness": "indirect", "limitations": "Open-label design (no blinding), single-centre, small sample size, control group received no intervention rather than a placebo", "followUp": "4 weeks", "plainFinding": "Probiotic milk eased hard stools.", "retracted": false, "expressionOfConcern": false, "hasErratum": false, "url": "https://pubmed.ncbi.nlm.nih.gov/41980711/", "sourceText": "Fermented milk containing Lacticaseibacillus paracasei strain Shirota (LcS) has been shown to improve stool consistency in various countries; however, its effect on hard or lumpy stools (HLS) in the Vietnamese population remains unclear. We investigated the effects of LcS-fermented milk on constipated Vietnamese adults with a high prevalence of HLS. In a single-centre, open-label trial, 51 participants with HLS were randomised to receive one bottle per day of fermented milk containing ≥6.5 × 109 cfu of LcS for 4 weeks (probiotic group) or no intervention (control group), followed by a 2-week washout. The primary endpoint was the proportion of participants with HLS (Bristol Stool Form Scale score of 1 or 2) in ≥25% of bowel movements over 4 weeks. Secondary endpoints included total stool frequency, HLS frequency, ideal stool form, and defecation-related symptoms - all recorded in daily diaries. The Chinese Constipation Questionnaire (CCQ) and gut microbiota composition (16S rRNA sequencing) were assessed every 2 weeks. During the intervention, the probiotic group had a significantly lower proportion of participants with HLS in ≥25% of bowel movements compared to controls (odds ratio: 0.00; 95% confidence interval: 0.00-0.16; P = 0.005). The probiotic group also showed increased total stool frequency ( P = 0.001), reduced HLS frequency ( P = 0.035), and fewer participants with CCQ scores ≥5 indicating constipation ( P < 0.001) at 4 weeks. Gut microbiota beta-diversity differed between groups after 2 weeks ( P = 0.031), with reductions in Peptococcaceae, Clostridium_methylpentosum_group, and Clostridia (unclassified at the order level), followed by increases in Lachnospiraceae_UCG-004 at 4 weeks and Lachnospiraceae_ND3007_group post-follow-up ( P < 0.050), suggesting microbial changes linked to constipation improvement. No serious adverse events related to the intervention were observed. These findings support daily LcS-fermented milk as a dietary strategy in Vietnam to manage constipation via gut microbiota modulation. The study was registered at ClinicalTrials.gov (ID: NCT05982743).", "provenance": [ { "field": "n", "quote": "51 participants with HLS were randomised" }, { "field": "population", "quote": "constipated Vietnamese adults with a high prevalence of HLS" }, { "field": "intervention", "quote": "one bottle per day of fermented milk containing ≥6.5 × 109 cfu of LcS for 4 weeks (probiotic group)" }, { "field": "comparator", "quote": "no intervention (control group)" }, { "field": "primaryOutcome", "quote": "The primary endpoint was the proportion of participants with HLS (Bristol Stool Form Scale score of 1 or 2) in ≥25% of bowel movements over 4 weeks." }, { "field": "result", "quote": "the probiotic group had a significantly lower proportion of participants with HLS in ≥25% of bowel movements compared to controls (odds ratio: 0.00; 95% confidence interval: 0.00-0.16; P = 0.005)" }, { "field": "result", "quote": "The probiotic group also showed increased total stool frequency ( P = 0.001), reduced HLS frequency ( P = 0.035), and fewer participants with CCQ scores ≥5 indicating constipation ( P < 0.001) at 4 weeks." } ] }, { "id": "pmid:41748755", "pmid": "41748755", "doi": "10.1007/s00384-026-05105-x", "nctId": null, "pmcid": "PMC12945974", "title": "Surgical management of anal stenosis following hemorrhoid treatment: a single-center case series", "firstAuthor": "Do", "multipleAuthors": true, "journal": "Int J Colorectal Dis", "year": 2026, "design": "case-series", "n": 13, "nField": "reported", "population": "patients with anal narrowing (stenosis) after hemorrhoid surgery", "intervention": "surgery to release the scar/fibrotic ring, sometimes combined with rectal tissue repair (mucosal advancement, suturing, or V-Y flap)", "comparator": "different surgical techniques compared to each other (no untreated or non-surgical comparison group)", "primaryOutcome": "ability to pass stool normally, stool thickness, and absence of pain or bleeding after surgery", "result": "12 of 13 patients had good outcomes, healing in about 2 months on average; 1 patient had the problem come back and needed another operation", "resultDirection": "benefit", "quality": "low", "qualityWhy": "This is a small, uncontrolled case series of only 13 patients, so it cannot reliably prove the surgery caused the improvement.", "directness": "indirect", "limitations": "Small sample size, no comparison group, retrospective design, and it addresses anal narrowing after hemorrhoid surgery rather than the general question of long stool size.", "followUp": "13.3 months (range 6-24 months)", "plainFinding": "Surgery fixed narrowed anus, not stool size.", "retracted": false, "expressionOfConcern": false, "hasErratum": false, "url": "https://pubmed.ncbi.nlm.nih.gov/41748755/", "sourceText": "OBJECTIVE: To describe the clinical characteristics, causes, classification, and surgical techniques used to treat anal stenosis following hemorrhoid surgery, as well as to evaluate the treatment outcomes based on specific clinical criteria. SUBJECTS AND METHODS: This retrospective case series included 13 patients with anal stenosis after hemorrhoidectomy. All underwent surgical treatment at Viet Duc University Hospital between January 2022 and June 2024. Surgical techniques applied were fibrotic ring release alone, fibrotic ring release with rectal mucosal advancement, fibrotic ring release with horizontal suturing of the rectal mucosa, and fibrotic ring release with V-Y flap reconstruction. Outcomes were assessed based on patients' ability to achieve normal defecation, stool caliber, and the absence of anal pain or bleeding postoperatively. Successful treatment was defined as normalized stool passage without pain or the need for stool softeners. RESULTS: Surgical outcomes were favorable in 12 out of 13 patients (92.3%), with an average healing time of 2.0 ± 1.1 months. The mean follow-up was 13.3 months (range 6-24 months; minimum 6 months). Patients treated with fibrotic ring release alone experienced the longest healing time, while those who underwent mucosal advancement or V-Y flap reconstruction had shorter recovery periods. Recurrence occurred in one patient who required reoperation. CONCLUSION: Anal stenosis is a rare but serious complication following hemorrhoid surgery. Surgical interventions, including fibrotic ring release and anoplasty, appeared to be effective and safe, with favorable short-term outcomes in most patients.", "provenance": [ { "field": "population", "quote": "13 patients with anal stenosis after hemorrhoidectomy" }, { "field": "intervention", "quote": "fibrotic ring release alone, fibrotic ring release with rectal mucosal advancement, fibrotic ring release with horizontal suturing of the rectal mucosa, and fibrotic ring release with V-Y flap reconstruction" }, { "field": "comparator", "quote": "Patients treated with fibrotic ring release alone experienced the longest healing time, while those who underwent mucosal advancement or V-Y flap reconstruction had shorter recovery periods" }, { "field": "primaryOutcome", "quote": "Outcomes were assessed based on patients' ability to achieve normal defecation, stool caliber, and the absence of anal pain or bleeding postoperatively" }, { "field": "result", "quote": "Surgical outcomes were favorable in 12 out of 13 patients (92.3%), with an average healing time of 2.0 ± 1.1 months" }, { "field": "n", "quote": "This retrospective case series included 13 patients with anal stenosis after hemorrhoidectomy" } ] }, { "id": "pmid:41611088", "pmid": "41611088", "doi": "10.1016/j.ajcnut.2026.101212", "nctId": null, "pmcid": "PMC12975388", "title": "Fiber intake and laxation in people with normal bowel function: a systematic review", "firstAuthor": "Balk", "multipleAuthors": true, "journal": "Am J Clin Nutr", "year": 2026, "design": "systematic-review", "n": null, "nField": "not-reported", "population": "healthy adults with normal bowel function", "intervention": "higher dietary fiber intake", "comparator": "lower fiber intake or different fiber types", "primaryOutcome": "stool consistency, fecal weight, bowel movement frequency, and gut transit time", "result": "more fiber modestly softened stool, increased fecal weight and frequency, and shortened gut transit time, with low-solubility, low-fermentability fibers having the strongest effects", "resultDirection": "benefit", "quality": "moderate", "qualityWhy": "Based on many randomized trials with low-to-moderate bias, but the authors say findings come from indirect modeling rather than direct dose comparisons in most individual trials.", "directness": "indirect", "limitations": "The authors state findings are indirect, based on statistical models rather than direct trial comparisons, and that there is insufficient evidence in specific subpopulations.", "followUp": "", "plainFinding": "More fiber means bulkier, more frequent stools.", "retracted": false, "expressionOfConcern": false, "hasErratum": false, "url": "https://pubmed.ncbi.nlm.nih.gov/41611088/", "sourceText": "BACKGROUND: Optimal evidence-based dietary recommendations for dietary fiber have not been established. OBJECTIVES: This study aims to conduct a systematic review of fiber and gut motility (laxation) in noninfants with normal bowel function. METHODS: We searched PubMed, Embase, and CINAHL from inception through 4 March, 2025, and existing systematic review reference lists. We included randomized controlled trials (RCTs) in the general population without bowel dysfunction that compared fiber amounts or types and assessed stool consistency, fecal weight, fecal frequency, or gut transit time. We categorized fibers according to their solubility, viscosity, and fermentability and performed hierarchical Bayesian regression models and spline analyses across reported total and added fiber intake doses, with subanalyses by fiber type. We assessed study risk of bias and strength of evidence (SoE). RESULTS: We identified 113 eligible trials, with low or moderate risk of bias. Models provided moderate SoE that increasing fiber intake (per g/d total fiber) yields softening stool consistency [0.013 units, 95% credible interval (CrI): 0.009, 0.016 on the Bristol Stool Scale], increasing total fecal weight (1.76 g/d, 95% CrI: 1.58, 1.94) and dry fecal weight (0.47 g/d, 95% CrI: 0.42, 0.51), increasing fecal frequency (0.053 additional bowel movements/wk, 95% CrI: 0.042, 0.065), and shortening gut transit times (-0.24 h, 95% CrI: -0.36, -0.12). Associations between fiber intake and outcomes varied across fiber doses and type. Low-solubility and low-fermentability fibers had the strongest associations with laxation outcomes, with low to medium SoE. However, findings are indirect, based on models, and there is insufficient evidence in specific subpopulations. CONCLUSIONS: RCTs support small to modest effects of dietary fiber on laxation in generally healthy people with normal bowel function. Low-solubility and low-fermentability fibers yielded the strongest effects. Future studies should better characterize fiber properties, assess wider ranges of fiber doses, and comprehensively report participants' total and background fiber intake. This study was registered at PROSPERO as CRD42024522380.", "provenance": [ { "field": "population", "quote": "general population without bowel dysfunction" }, { "field": "intervention", "quote": "increasing fiber intake (per g/d total fiber)" }, { "field": "comparator", "quote": "compared fiber amounts or types" }, { "field": "primaryOutcome", "quote": "assessed stool consistency, fecal weight, fecal frequency, or gut transit time" }, { "field": "result", "quote": "increasing fiber intake (per g/d total fiber) yields softening stool consistency [0.013 units, 95% credible interval (CrI): 0.009, 0.016 on the Bristol Stool Scale], increasing total fecal weight (1.76 g/d, 95% CrI: 1.58, 1.94) and dry fecal weight (0.47 g/d, 95% CrI: 0.42, 0.51), increasing fecal frequency (0.053 additional bowel movements/wk, 95% CrI: 0.042, 0.065), and shortening gut transit times (-0.24 h, 95% CrI: -0.36, -0.12)" }, { "field": "limitations", "quote": "findings are indirect, based on models, and there is insufficient evidence in specific subpopulations" } ] }, { "id": "pmid:41424727", "pmid": "41424727", "doi": "10.7717/peerj.20479", "nctId": null, "pmcid": "PMC12716137", "title": "The investigation of fermented food consumption on gastrointestinal symptoms: a cross-sectional study in university students", "firstAuthor": "Seven Avuk", "multipleAuthors": true, "journal": "PeerJ", "year": 2025, "design": "retrospective", "n": 546, "nField": "reported", "population": "university students who completed a survey", "intervention": "frequency of eating fermented foods like yogurt, kefir, vinegar, cheese, pickles, sourdough bread", "comparator": "different frequencies of fermented food consumption among students", "primaryOutcome": "gastrointestinal symptoms (bloating, pain, reflux) and stool consistency", "result": "Students who ate more yogurt, kefir, vinegar, cheese, and pickles had fewer gastrointestinal symptoms, and those with normal stool consistency had fewer symptoms than those with constipation", "resultDirection": "benefit", "quality": "low", "qualityWhy": "This is a one-time survey of students' habits, not a controlled trial, so it can only show a link, not prove fermented foods cause fewer symptoms or affect stool length.", "directness": "indirect", "limitations": "Cross-sectional, self-reported food frequency questionnaire and symptom scales; cannot establish cause and effect.", "followUp": "", "plainFinding": "More fermented foods linked to fewer GI symptoms.", "retracted": false, "expressionOfConcern": false, "hasErratum": false, "url": "https://pubmed.ncbi.nlm.nih.gov/41424727/", "sourceText": "BACKGROUND: Fermented foods (FFs) are a valuable source of live microorganisms that can enhance human health, particularly gastrointestinal health, akin to probiotics. This study investigated the relationship between FFs consumption habits and gastrointestinal system findings in university students. METHODS: A cross-sectional anonymous survey included 546 university students, collecting data on sociodemographic characteristics, the Gastrointestinal Symptom Rating Scale (GSRS), and the Bristol Stool Form Scale (BSFS). FFs consumption habits were recorded using a food frequency questionnaire. RESULTS: Results showed that the average GSRS score was 33.66 ± 16.89. According to the BSFS, 15% of students experienced constipation, 72.7% had moderate stool consistency, and 12.3% had diarrhea. Notably, kefir, vinegar, and sourdough bread were never consumed by 56.8%, 44.3%, and 41.9% of students, respectively. Significant differences were found between the frequency of yogurt, kefir, vinegar, cheese, pickle consumption, and gastrointestinal symptoms (p < 0.05). Students with normal stool consistency had fewer dyspepsia, abdominal pain, reflux symptoms, and overall gastrointestinal symptoms than those with constipation (p < 0.05). CONCLUSION: The study concludes that FFs such as yogurt, cheese, pickles, and kefir may offer health benefits, reducing symptoms of reflux, dyspepsia, abdominal pain, and general gastrointestinal issues in young adults.", "provenance": [ { "field": "n", "quote": "included 546 university students" }, { "field": "population", "quote": "university students" }, { "field": "intervention", "quote": "FFs consumption habits were recorded using a food frequency questionnaire" }, { "field": "comparator", "quote": "Significant differences were found between the frequency of yogurt, kefir, vinegar, cheese, pickle consumption, and gastrointestinal symptoms" }, { "field": "primaryOutcome", "quote": "collecting data on sociodemographic characteristics, the Gastrointestinal Symptom Rating Scale (GSRS), and the Bristol Stool Form Scale (BSFS)" }, { "field": "result", "quote": "Students with normal stool consistency had fewer dyspepsia, abdominal pain, reflux symptoms, and overall gastrointestinal symptoms than those with constipation (p < 0.05)." } ] }, { "id": "pmid:41327986", "pmid": "41327986", "doi": "10.24953/turkjpediatr.2025.6367", "nctId": null, "pmcid": null, "title": "Abdominal massage as an adjunctive therapy for pediatric functional constipation: a randomized controlled trial", "firstAuthor": "Malekiantaghi", "multipleAuthors": true, "journal": "Turk J Pediatr", "year": 2025, "design": "rct", "n": 61, "nField": "reported", "population": "children aged 4 to 10 years with chronic functional constipation", "intervention": "abdominal massage (12 sessions) added to standard constipation medication", "comparator": "standard constipation medication alone", "primaryOutcome": "stool consistency, constipation severity, and fecal incontinence episodes", "result": "No significant difference in stool consistency between groups, but the massage group had a greater reduction in constipation severity scores and fewer fecal incontinence episodes", "resultDirection": "mixed", "quality": "low", "qualityWhy": "Small trial of 61 children with short-term outcomes and no mention of blinding, so results need confirmation in larger studies.", "directness": "indirect", "limitations": "Abstract notes larger, multicenter trials are needed to confirm findings; no blinding described.", "followUp": "", "plainFinding": "Less constipation and leakage, not stool consistency.", "retracted": false, "expressionOfConcern": false, "hasErratum": false, "url": "https://pubmed.ncbi.nlm.nih.gov/41327986/", "sourceText": "BACKGROUND: Chronic functional constipation affects approximately 3% of children globally, leading to painful defecation, fecal incontinence, and abdominal discomfort. Abdominal massage may improve gastrointestinal motility by stimulating vagal activity and reducing abdominal muscle tension. This study aimed to evaluate the effectiveness of abdominal massage therapy as an adjunct treatment for chronic functional constipation in children. METHODS: This randomized controlled trial included 61 children aged 4-10 years (mean age 6.36 ± 1.77) diagnosed with functional constipation. Participants were randomly assigned to two groups: the control group, receiving standard drug therapy, and the intervention group, receiving 12 sessions of Swedish abdominal massage involving effleurage and gentle pressing, vibration of the small and large intestines, kneading of the abdomen, and clockwise circular movements in addition to drug treatment. Outcomes assessed included stool consistency (using the Bristol Stool Scale), constipation severity (measured by the Constipation Assessment Scale), and associated symptoms. RESULTS: Both groups showed improvements in stool consistency; however, no statistically significant difference was found between them. The intervention group demonstrated a significantly greater reduction in constipation symptoms (Constipation Assessment Scale scores decreased from 14.70 ± 1.29 to 10.21 ± 1.45, P < 0.001.) and fewer episodes of fecal incontinence (from 3.82 ± 1.33 to 2.70 ± 1.33 days/week, P < 0.001) compared to the control group. CONCLUSION: A 12-session abdominal massage therapy program appears to be an effective adjunct treatment to standard pharmacological therapy for alleviating constipation-related symptoms in children. Larger, multicenter trials are needed to confirm these findings.", "provenance": [ { "field": "n", "quote": "This randomized controlled trial included 61 children aged 4-10 years" }, { "field": "population", "quote": "61 children aged 4-10 years (mean age 6.36 ± 1.77) diagnosed with functional constipation" }, { "field": "intervention", "quote": "the intervention group, receiving 12 sessions of Swedish abdominal massage involving effleurage and gentle pressing, vibration of the small and large intestines, kneading of the abdomen, and clockwise circular movements in addition to drug treatment" }, { "field": "comparator", "quote": "the control group, receiving standard drug therapy" }, { "field": "primaryOutcome", "quote": "Outcomes assessed included stool consistency (using the Bristol Stool Scale), constipation severity (measured by the Constipation Assessment Scale), and associated symptoms." }, { "field": "result", "quote": "Both groups showed improvements in stool consistency; however, no statistically significant difference was found between them. The intervention group demonstrated a significantly greater reduction in constipation symptoms (Constipation Assessment Scale scores decreased from 14.70 ± 1.29 to 10.21 ± 1.45, P < 0.001.) and fewer episodes of fecal incontinence (from 3.82 ± 1.33 to 2.70 ± 1.33 days/week, P < 0.001) compared to the control group." } ] }, { "id": "pmid:41193362", "pmid": "41193362", "doi": "10.1016/j.jpurol.2025.10.011", "nctId": null, "pmcid": null, "title": "Beyond the Rome IV criteria: Diagnostic accuracy of clinical tools for functional constipation in children and adolescents", "firstAuthor": "Estevam de Abreu", "multipleAuthors": true, "journal": "J Pediatr Urol", "year": 2026, "design": "case-series", "n": 106, "nField": "reported", "population": "children and teenagers aged 4-17 being evaluated for possible constipation in pediatric and urology clinics", "intervention": "clinical scoring tools (Cleveland Clinic Constipation Score, Bristol Stool Scale, Dysfunctional Voiding Symptom Score, rectal diameter measurement) used to identify constipation", "comparator": "official Rome IV diagnostic criteria for constipation (used as the gold standard)", "primaryOutcome": "how accurately each tool identified functional constipation compared to the Rome IV criteria", "result": "the constipation score tool was most accurate (92.1%), one voiding-symptom question was moderately accurate (72.5%), while stool shape scale and rectal diameter were poorly accurate (under 60%)", "resultDirection": "mixed", "quality": "low", "qualityWhy": "this was a cross-sectional comparison of scoring tools in a relatively small group, so it shows which tools match a diagnosis rather than why stools are long or what causes constipation.", "directness": "indirect", "limitations": "abstract does not describe blinding, how patients were selected beyond age range and clinic type, or any assessment of long-term outcomes.", "followUp": "", "plainFinding": "Symptom scores help diagnose constipation accurately.", "retracted": false, "expressionOfConcern": false, "hasErratum": false, "url": "https://pubmed.ncbi.nlm.nih.gov/41193362/", "sourceText": "INTRODUCTION: Functional constipation (FC) is the most prevalent digestive complaint in children and adolescents, significantly impacting quality of life and often associated with fecal incontinence, emotional disturbances, and urinary symptoms. Although its diagnosis is primarily clinical and based on the Rome IV criteria, the lack of objective severity parameters and reliance on self-reported symptoms can hinder early identification. In this context, the present study aimed to evaluate the diagnostic accuracy of commonly used auxiliary tools - the pediatric-adapted Cleveland Clinic Constipation Score (CCS), the Bristol Stool Scale, the Dysfunctional Voiding Symptom Score (DVSS), and rectal diameter (RD) - using the Rome IV criteria as the gold standard. METHODS: This cross-sectional study included 106 patients aged 4-17 years, evaluated in general pediatric and specialized lower urinary tract dysfunction outpatient clinics. Each assessment tool was compared against the Rome IV criteria in terms of sensitivity, specificity, and overall accuracy. RESULTS: The CCS demonstrated the highest diagnostic accuracy (92.1 %), with a sensitivity of 89.5 % and specificity of 80.0 %, establishing it as an effective tool not only for diagnosing FC but also for grading its severity. Item 4 of the DVSS, which assesses the perception of effort during defecation, showed an accuracy of 72.5 % and should be valued by healthcare professionals as a relevant marker of FC. In contrast, the Bristol Stool Scale (types 1 and 2), RD measurement, and DVSS item 3 (bowel movement frequency) presented low accuracy levels (<60 %). CONCLUSION: With its high accuracy, the CCS has proven to be a valid and reliable tool that supports the diagnosis of functional constipation and may also assist in determining its severity. Additionally, DVSS item 4 proves useful in clinical evaluation, while other instruments should be considered auxiliary tools, applied selectively based on individual patient needs.", "provenance": [ { "field": "n", "quote": "This cross-sectional study included 106 patients aged 4-17 years" }, { "field": "population", "quote": "evaluated in general pediatric and specialized lower urinary tract dysfunction outpatient clinics" }, { "field": "intervention", "quote": "the pediatric-adapted Cleveland Clinic Constipation Score (CCS), the Bristol Stool Scale, the Dysfunctional Voiding Symptom Score (DVSS), and rectal diameter (RD)" }, { "field": "comparator", "quote": "using the Rome IV criteria as the gold standard" }, { "field": "primaryOutcome", "quote": "Each assessment tool was compared against the Rome IV criteria in terms of sensitivity, specificity, and overall accuracy." }, { "field": "result", "quote": "The CCS demonstrated the highest diagnostic accuracy (92.1 %), with a sensitivity of 89.5 % and specificity of 80.0 %" }, { "field": "result", "quote": "Item 4 of the DVSS, which assesses the perception of effort during defecation, showed an accuracy of 72.5 %" }, { "field": "result", "quote": "the Bristol Stool Scale (types 1 and 2), RD measurement, and DVSS item 3 (bowel movement frequency) presented low accuracy levels (<60 %)" } ] }, { "id": "pmid:41180988", "pmid": "41180988", "doi": "10.3748/wjg.v31.i40.112637", "nctId": null, "pmcid": "PMC12576558", "title": "Comprehensive microbial and clinical profiling of functional constipation: A stratified comparative study of age and constipation subtype", "firstAuthor": "Zhu", "multipleAuthors": true, "journal": "World J Gastroenterol", "year": 2025, "design": "case-control", "n": 126, "nField": "reported", "population": "Adults with functional constipation (grouped by age: young, middle-aged, older) compared with healthy people without constipation", "intervention": "Gut microbiota profiling (16S rRNA sequencing) stratified by age group and constipation subtype, along with anorectal and transit testing", "comparator": "Healthy control participants without constipation", "primaryOutcome": "Differences in gut microbial composition and their relation to constipation subtype, age, and anorectal/motility measurements", "result": "Microbial diversity and composition differed significantly by age group and by constipation subtype (slow-transit vs defecatory disorder), with different bacteria linked to sphincter tone, peristalsis speed, and inflammation in each group", "resultDirection": "unclear", "quality": "low", "qualityWhy": "This is a small, non-randomized comparison of stool bacteria across groups, so it can show patterns but not prove what causes constipation or stool characteristics.", "directness": "indirect", "limitations": "Observational comparative study with limited sample size (92 patients, 34 controls); no intervention tested; does not address stool length or size specifically.", "followUp": "", "plainFinding": "Gut bacteria differ by age and constipation type.", "retracted": false, "expressionOfConcern": false, "hasErratum": false, "url": "https://pubmed.ncbi.nlm.nih.gov/41180988/", "sourceText": "BACKGROUND: Gut microbiota dysbiosis plays a central role in the pathogenesis of functional constipation (FC), but clinical treatment has shown uneven efficacy through methods of regulating intestinal flora. Most existing studies have concentrated on overall case-control comparisons, with limited stratification by age or constipation subtype. Knowledge of how these factors shape gut microbiota composition remains inadequate, constraining the development of effective personalized microbiota-based interventions. AIM: To characterize gut microbiota profiles by age and constipation subtype and identify factors associated with microbial composition in FC. METHODS: Ninety-two patients with FC completed questionnaires and underwent anorectal manometry and gastrointestinal transit tests; stool samples were collected for 16S rRNA gene sequencing. Stool samples alone were collected from 34 healthy controls. Patients with FC were categorized into age groups (young, middle-aged, and older) and classified into normal-transit constipation, slow-transit constipation (STC), defecatory disorder (DD), and mixed constipation subtypes. Gut microbial compositions across age groups and constipation subtypes were compared, and their correlations with clinical parameters were investigated. RESULTS: The young group demonstrated significantly higher anal resting and squeeze pressures than the middle-aged and the older groups. Microbial richness and diversity were substantially lower in the older group than in middle-aged and young groups. Gut microbiota in the young group was predominantly enriched in taxa increasing sphincter tone and inhibiting intestinal peristalsis; the older group featured abundances of short-chain fatty acid-producing, beneficial taxa. The middle-aged group showed an enrichment of pro-inflammatory and pathogenic bacteria. Microbial richness and diversity were higher in STC than in the DD group. Moreover, STC group was enriched in taxa associated with slower peristalsis; DD group showed enrichment of motility-promoting taxa. CONCLUSION: Significant differences in microbial composition and function were observed across age groups and constipation subtypes in FC, suggesting underlying pathophysiological heterogeneity and providing a basis for precision diagnosis and treatment.", "provenance": [ { "field": "n", "quote": "Ninety-two patients with FC completed questionnaires and underwent anorectal manometry and gastrointestinal transit tests; stool samples were collected for 16S rRNA gene sequencing. Stool samples alone were collected from 34 healthy controls." }, { "field": "population", "quote": "Patients with FC were categorized into age groups (young, middle-aged, and older) and classified into normal-transit constipation, slow-transit constipation (STC), defecatory disorder (DD), and mixed constipation subtypes." }, { "field": "intervention", "quote": "Gut microbial compositions across age groups and constipation subtypes were compared, and their correlations with clinical parameters were investigated." }, { "field": "comparator", "quote": "Stool samples alone were collected from 34 healthy controls." }, { "field": "primaryOutcome", "quote": "To characterize gut microbiota profiles by age and constipation subtype and identify factors associated with microbial composition in FC." }, { "field": "result", "quote": "Significant differences in microbial composition and function were observed across age groups and constipation subtypes in FC, suggesting underlying pathophysiological heterogeneity and providing a basis for precision diagnosis and treatment." } ] }, { "id": "pmid:41047557", "pmid": "41047557", "doi": "10.1080/19490976.2025.2559119", "nctId": null, "pmcid": "PMC12502818", "title": "First insights into microbial changes within an Inflammatory Bowel Disease Family Cohort study", "firstAuthor": "Rausch", "multipleAuthors": true, "journal": "Gut Microbes", "year": 2025, "design": "prospective-cohort", "n": null, "nField": "not-reported", "population": "IBD patients and their relatives, a population at high risk for IBD development", "intervention": "none - observational collection of microbial, health and lifestyle data over time (no treatment given)", "comparator": "external IBD cohorts used for validation of findings", "primaryOutcome": "factors influencing the gut microbiota in health and IBD disease, including dysbiosis patterns", "result": "Community gradients correspond strongly with IBD pathologies, physiological manifestations of inflammation (e.g. Bristol stool score, ASCA IgA, ASCA IgG), and genetic risk for IBD. Anthropometric and medical factors influencing fecal transit time strongly modify bacterial communities.", "resultDirection": "unclear", "quality": "low", "qualityWhy": "This is an observational cohort study of IBD patients and relatives looking at microbiome patterns, not a controlled study designed to explain why stool is long.", "directness": "indirect", "limitations": "Abstract does not report participant numbers, follow-up duration, or statistical details, and focuses on IBD-specific microbial dysbiosis rather than stool length in general.", "followUp": "", "plainFinding": "Gut bacteria linked to bowel transit time.", "retracted": false, "expressionOfConcern": false, "hasErratum": false, "url": "https://pubmed.ncbi.nlm.nih.gov/41047557/", "sourceText": "The prospective Kiel Inflammatory Bowel Disease (IBD) Family Cohort Study (KINDRED cohort) was initiated in 2013 to systematically and extensively collect data and biosamples from index IBD patients and their relatives, a population at high risk for IBD development. Regular follow-ups were conducted to collect updated health and lifestyle information, to obtain new biosamples, and to capture the incidence of IBD during development. By combining microbial data collected at successive time points with extensive anthropometric, medical, nutritional, and social information, this study aimed to characterize the factors influencing the microbiota in health and disease via detailed ecological analyses. Using a microbial dysbiosis metric based on the German KINDRED cohort, we identified strong and generalizable gradients within and across different external IBD cohorts for validation. These community gradients correspond strongly with IBD pathologies, physiological manifestations of inflammation (e.g. Bristol stool score, ASCA IgA, ASCA IgG), and genetic risk for IBD. Anthropometric and medical factors influencing fecal transit time strongly modify bacterial communities. Various Enterobacteriaceae (e.g. Klebsiella sp.) and opportunistic Clostridia pathogens (e.g. C. XIVa clostridioforme), characterize in combination with ectopically colonizing oral taxa (e.g. Veillonella sp. Cand. Saccharibacteria sp. Fusobacterium nucleatum) the distinct and chaotic IBD-specific communities. Weak community and physiological changes are further traceable in a small number of individuals, who developed IBD in the study's runtime. Our findings demonstrate broad-scale ecological patterns which indicate drastic state transitions of communities in IBD patients. These patterns appear to be universal across cohorts and influence physiological signs of inflammation, display increased resilience, but show only limited heritability/intrafamily transmission.", "provenance": [ { "field": "population", "quote": "index IBD patients and their relatives, a population at high risk for IBD development" }, { "field": "intervention", "quote": "systematically and extensively collect data and biosamples from index IBD patients and their relatives" }, { "field": "comparator", "quote": "strong and generalizable gradients within and across different external IBD cohorts for validation" }, { "field": "primaryOutcome", "quote": "characterize the factors influencing the microbiota in health and disease via detailed ecological analyses" }, { "field": "result", "quote": "These community gradients correspond strongly with IBD pathologies, physiological manifestations of inflammation (e.g. Bristol stool score, ASCA IgA, ASCA IgG), and genetic risk for IBD." }, { "field": "result", "quote": "Anthropometric and medical factors influencing fecal transit time strongly modify bacterial communities." } ] }, { "id": "pmid:41034384", "pmid": "41034384", "doi": "10.1038/s41598-025-16321-w", "nctId": null, "pmcid": "PMC12488941", "title": "A randomized trial of inulin for bowel symptoms, depression and quality of life in constipation predominant IBS", "firstAuthor": "Akçalı", "multipleAuthors": true, "journal": "Sci Rep", "year": 2025, "design": "rct", "n": 34, "nField": "reported", "population": "adults aged 21 to 63 with constipation-predominant IBS", "intervention": "inulin/oligofructose prebiotic supplement", "comparator": "maltodextrin placebo", "primaryOutcome": "bowel symptoms, quality of life, and depression scores", "result": "IBS quality of life score rose and symptom severity score fell in the inulin group, with improved constipation and psychological state ratings", "resultDirection": "benefit", "quality": "low", "qualityWhy": "This was a small, single-blind trial of only 34 people over just 8 weeks, so the results are an early signal rather than strong proof.", "directness": "indirect", "limitations": "small sample size, single-blind design (not double-blind), short 8-week intervention period", "followUp": "8 weeks", "plainFinding": "Eased constipation symptoms in IBS.", "retracted": false, "expressionOfConcern": false, "hasErratum": false, "url": "https://pubmed.ncbi.nlm.nih.gov/41034384/", "sourceText": "This study was conducted to evaluate the effect of inulin on bowel symptoms, depression and quality of life in individuals with constipation-predominant irritable bowel syndrome. This study was designed as a randomized, single-blind, placebo-controlled clinical trial with a parallel design and a 1:1 allocation ratio. Individuals (n = 34) aged between 21 and 63 years with constipation-predominant IBS were included in the study. Individuals were randomly assigned to two groups: the prebiotic group (n = 17), which received a 50%/50% mixture of inulin/oligofructose (4.6 g twice daily, for a total daily dose of 9.2 g), and the placebo group (n = 17), which total received 9.2 g of maltodextrin per day. The intervention period was 8 weeks. Bristol Stool Scale, IBS-Visual Analogue Scale (IBS-VAS), IBS-Symptom Severity Score Scale (IBS-SSS), IBS-Quality of Life Scale (IBS-QoL) and Beck Depression Scale were administered to the participants at the beginning, 1st month and 2nd month. As a result, total IBS-QoL score increased in the prebiotic group (61.0 ± 19.4 to 77.4 ± 15.1; p < 0.006), whereas total IBS-SSS score decreased (267.3 ± 56.0 to 195.8 ± 59.0; p < 0.026). In the prebiotic group, significant improvement was observed in the IBS-VAS parameters of constipation status (2.2 ± 2.3 to 4.9 ± 2.5; p < 0.042group×time), psychological state (7 (2-10) to 9 (5-10); p < 0.006). It is thought that inulin may have beneficial effects on reducing symptom severity and frequency and on quality of life in individuals with IBS in whom constipation is predominant.", "provenance": [ { "field": "n", "quote": "Individuals (n = 34) aged between 21 and 63 years with constipation-predominant IBS were included in the study" }, { "field": "population", "quote": "Individuals (n = 34) aged between 21 and 63 years with constipation-predominant IBS were included in the study" }, { "field": "intervention", "quote": "the prebiotic group (n = 17), which received a 50%/50% mixture of inulin/oligofructose (4.6 g twice daily, for a total daily dose of 9.2 g)" }, { "field": "comparator", "quote": "the placebo group (n = 17), which total received 9.2 g of maltodextrin per day" }, { "field": "primaryOutcome", "quote": "This study was conducted to evaluate the effect of inulin on bowel symptoms, depression and quality of life in individuals with constipation-predominant irritable bowel syndrome" }, { "field": "result", "quote": "total IBS-QoL score increased in the prebiotic group (61.0 ± 19.4 to 77.4 ± 15.1; p < 0.006), whereas total IBS-SSS score decreased (267.3 ± 56.0 to 195.8 ± 59.0; p < 0.026)" }, { "field": "followUp", "quote": "The intervention period was 8 weeks" } ] }, { "id": "pmid:41000790", "pmid": "41000790", "doi": "10.1101/2024.06.05.597641", "nctId": null, "pmcid": "PMC12458959", "title": "Early life gut microbial and metabolic shifts reflected in stool consistency- a gut transit time proxy", "firstAuthor": "Aatsinki", "multipleAuthors": true, "journal": "bioRxiv", "year": 2025, "design": "prospective-cohort", "n": 618, "nField": "reported", "population": "infants and young children aged 2.5 to 30 months from a birth cohort study", "intervention": "breastfeeding status (exclusive vs partial) and gut microbial/metabolite composition", "comparator": "partial versus exclusive breastfeeding", "primaryOutcome": "stool water content and parent-reported stool consistency", "result": "breastfeeding had the strongest association with stool consistency and water content, and certain bacterial metabolites (bile acid amidates, SCFAs) were linked to firmer or looser stools", "resultDirection": "mixed", "quality": "low", "qualityWhy": "This is an observational, correlational study in infants from a preprint that has not yet been peer reviewed, so its findings are preliminary and not about adults or stool length specifically.", "directness": "indirect", "limitations": "Preprint not peer-reviewed; observational/correlational design; studies infants aged 2.5-30 months, not adults; does not address stool length specifically.", "followUp": "", "plainFinding": "Breastfeeding and gut bacteria shape infant stool firmness.", "retracted": false, "expressionOfConcern": false, "hasErratum": false, "url": "https://pubmed.ncbi.nlm.nih.gov/41000790/", "sourceText": "Transit time, fluid intake, diet, and overall gut health all influence stool consistency. However, the relationships between the gut microbiota, metabolome (microbial metabolites), and stool consistency in infants and young children remain poorly understood. In this study, we analyzed the microbiota and metabolome of 618 stool samples from children aged 2.5 months (n = 360), 6 months (n = 229), 14 months (n = 274), and 30 months (n = 169) from the FinnBrain Birth Cohort Study, correlating these data with stool water content and parent-reported stool consistency. We found that breastfeeding had the strongest association with both stool consistency and fecal water content. We observed that the concentrations of newly discovered microbial bile acid amidates were associated with constipation and negatively correlated with stool water content. Partial versus exclusive breastfeeding was further linked to higher levels of specific bile acid amidates through mediation by constipation. Bile salt hydrolase, an enzyme involved in deconjugating primary bile acids and generating novel microbial bile acids, was also predicted to be negatively associated with stool water content. In addition, short-chain fatty acids (SCFAs), particularly acetic acids, were positively associated with stool water content, whereas branched SCFAs showed a negative association. These findings suggest longer transit time appeared to allow more extensive bacterial metabolism of microbial metabolites, including the transformation of bile acid amidates. Here, we also observed that the relative abundances of specific genera such as Clostridium, Hungatella, and Lactobacillus were associated with firmer stool consistency. Overall, our results highlight the importance of documenting stool consistency in fecal metabolomics and microbiome research, and provide new insights into how breastfeeding, microbial metabolism, and gut transit time shape early-life gut development.", "provenance": [ { "field": "n", "quote": "618 stool samples" }, { "field": "population", "quote": "618 stool samples from children aged 2.5 months (n = 360), 6 months (n = 229), 14 months (n = 274), and 30 months (n = 169) from the FinnBrain Birth Cohort Study" }, { "field": "intervention", "quote": "breastfeeding had the strongest association with both stool consistency and fecal water content" }, { "field": "comparator", "quote": "Partial versus exclusive breastfeeding was further linked to higher levels of specific bile acid amidates through mediation by constipation" }, { "field": "primaryOutcome", "quote": "correlating these data with stool water content and parent-reported stool consistency" }, { "field": "result", "quote": "We found that breastfeeding had the strongest association with both stool consistency and fecal water content." } ] }, { "id": "pmid:40780410", "pmid": "40780410", "doi": "10.1016/j.clnesp.2025.08.003", "nctId": null, "pmcid": null, "title": "Impact of prebiotics and postbiotics in the management of constipation: Analysis of their differentiated modulation of intestinal microbiota", "firstAuthor": "Culqui Lévano", "multipleAuthors": true, "journal": "Clin Nutr ESPEN", "year": 2025, "design": "rct", "n": 24, "nField": "reported", "population": "adults with constipation", "intervention": "a dextran prebiotic (NextDext™) or a prebiotic-postbiotic combination (ABB C24)", "comparator": "the two supplement types compared against each other", "primaryOutcome": "stool consistency (Bristol Stool Form Scale) and gut microbiome composition", "result": "significant improvement in stool consistency after taking NextDext™ from constipated to normal, with only a trend toward improvement after ABB C24", "resultDirection": "benefit", "quality": "low", "qualityWhy": "Very small study (24 people) over just two weeks, which limits how much confidence can be placed in the results.", "directness": "indirect", "limitations": "Abstract does not report dropout, blinding success, or statistical details beyond 'significant' and 'trend'; sample size is very small.", "followUp": "two weeks", "plainFinding": "Improved stool consistency with prebiotic supplement", "retracted": false, "expressionOfConcern": false, "hasErratum": false, "url": "https://pubmed.ncbi.nlm.nih.gov/40780410/", "sourceText": "Chronic constipation represents a burden in the modern world and is most prevalent in the elderly. Constipation has been linked to alterations in the gut microbiota, especially to an increase in methanogenic microorganisms. Prebiotics and some probiotics have already shown beneficial effects in constipation through improving stool consistency and modulating the gut microbiota. In the current double-blind, randomized and parallel-arm clinical study, 24 subjects with constipation were supplemented with NextDext™, a dextran prebiotic, or ABB C24, a prebiotic-postbiotic combination of NextDext™ and ABB C22®, for two weeks to evaluate their effects on stool consistency (Bristol Stool Form Scale) and gut microbiome. The results showed a significant improvement in stool consistency after taking NextDext™ from constipated to normal (Bristol Scale) and a trend to improvement after ABB C24 supplementation. Consumption of NextDext™ increased the presence of some beneficial bacterial groups, such as Bifidobacterium longum and Roseburia hominis, and reduced the presence of microorganisms associated with constipation, such as Blautia obeum, Escherichia coli and Collinsella aerofaciens. Consumption of ABB C24 reduced the presence of Blautia obeum and the methanogenic bacteria Methanobrevibacter smithii, while increased beneficial Clostridium leptum and Coprococcus spp. There were no significant alterations in gut diversity indexes of richness and evenness, even if ABB C24 seemed to increase diversity in a greater number of volunteers. Although NextDext™ influenced more microbial groups and restored microbial groups associated with opioid use, the species modulated by ABB C24 reverted microbial alterations consistently reported in constipation, suggesting an added value of the postbiotic ABB C22®. Both could benefit different profiles of constipation sufferers. This study was registered in ClinicalTrials.gov: NCT06738433.", "provenance": [ { "field": "n", "quote": "24 subjects with constipation" }, { "field": "population", "quote": "subjects with constipation" }, { "field": "intervention", "quote": "NextDext™, a dextran prebiotic, or ABB C24, a prebiotic-postbiotic combination of NextDext™ and ABB C22®, for two weeks" }, { "field": "comparator", "quote": "double-blind, randomized and parallel-arm clinical study" }, { "field": "primaryOutcome", "quote": "to evaluate their effects on stool consistency (Bristol Stool Form Scale) and gut microbiome" }, { "field": "result", "quote": "a significant improvement in stool consistency after taking NextDext™ from constipated to normal (Bristol Scale) and a trend to improvement after ABB C24 supplementation" }, { "field": "followUp", "quote": "for two weeks" } ] }, { "id": "pmid:40713395", "pmid": "40713395", "doi": "10.1016/j.dld.2025.07.011", "nctId": null, "pmcid": null, "title": "Multiomics insights into functional constipation: Exploring microbiome, metabolome, and lipidome independent of transit time", "firstAuthor": "Ryu", "multipleAuthors": true, "journal": "Dig Liver Dis", "year": 2025, "design": "case-control", "n": null, "nField": "not-reported", "population": "patients with functional constipation and healthy controls", "intervention": "fecal sampling before and after laxative administration", "comparator": "healthy controls", "primaryOutcome": "differences in gut microbiome, metabolome, and lipidome profiles", "result": "certain gut bacteria and metabolites differed between constipation patients and healthy controls, but lipid levels did not differ before and after laxative use", "resultDirection": "mixed", "quality": "low", "qualityWhy": "This is a small exploratory lab-style profiling study without a reported sample size, so its findings are not yet reliable evidence.", "directness": "indirect", "limitations": "No participant numbers given, and the abstract does not address stool length or size, only microbiome/metabolome/lipidome composition.", "followUp": "", "plainFinding": "Altered gut bacteria and metabolites in constipation.", "retracted": false, "expressionOfConcern": false, "hasErratum": false, "url": "https://pubmed.ncbi.nlm.nih.gov/40713395/", "sourceText": "BACKGROUND/AIMS: Functional constipation (FC) is a prevalent form of functional gastrointestinal disorder with an elusive etiology. Despite numerous investigations into the role of the gut microbiome in FC, no study has yet integrated microbiome, metabolome, and lipidome profiling to characterize FC. METHODS: In this study, fecal samples were collected from patients with FC both before and after laxative administration to minimize the impact of intestinal transit time and to identify the characteristics unique to patients with FC. These samples underwent comprehensive microbiome, metabolome, and lipidome analyses to discern the unique properties of FC. RESULTS: Beneficial microbiota such as Anerobutyricum hallii, Blautia luti, Blautia wexlerae, Collinsella aerofaciens, and Fusicatenibacter saccharivorans were predominantly found in healthy controls (HC), while harmful microbiota, Blautia faecis, was prevalent in patients with FC. Metabolome profiling showed that chenodeoxycholic acid, glucose, glycine, malic acid, phenylalanine, ribose, serine, and uracil decreased in patients with FC, suggesting a decreased energy metabolism and a reduced nutrient utilization for energy production compared to HCs. In terms of lipidome profiling, no significant differences in lipid levels were observed between pre- and post-laxative FC samples. CONCLUSIONS: Our findings offer novel insights into FC-specific alterations in the gut microbiota and metabolome and potentially lead to the development of targeted therapeutic approaches for FC.", "provenance": [ { "field": "population", "quote": "fecal samples were collected from patients with FC both before and after laxative administration" }, { "field": "intervention", "quote": "fecal samples were collected from patients with FC both before and after laxative administration to minimize the impact of intestinal transit time" }, { "field": "comparator", "quote": "Beneficial microbiota such as Anerobutyricum hallii, Blautia luti, Blautia wexlerae, Collinsella aerofaciens, and Fusicatenibacter saccharivorans were predominantly found in healthy controls (HC)" }, { "field": "primaryOutcome", "quote": "These samples underwent comprehensive microbiome, metabolome, and lipidome analyses to discern the unique properties of FC." }, { "field": "result", "quote": "Beneficial microbiota such as Anerobutyricum hallii, Blautia luti, Blautia wexlerae, Collinsella aerofaciens, and Fusicatenibacter saccharivorans were predominantly found in healthy controls (HC), while harmful microbiota, Blautia faecis, was prevalent in patients with FC." }, { "field": "result", "quote": "In terms of lipidome profiling, no significant differences in lipid levels were observed between pre- and post-laxative FC samples." } ] }, { "id": "pmid:40349171", "pmid": "40349171", "doi": "10.1002/advs.202503247", "nctId": null, "pmcid": "PMC12376671", "title": "AI-Driven Defecation Analysis by Smart Healthcare Toilet: Exploring Biometric Patterns and Eu-Tenesmus", "firstAuthor": "Song", "multipleAuthors": true, "journal": "Adv Sci (Weinh)", "year": 2025, "design": "prospective-cohort", "n": 11, "nField": "reported", "population": "11 people using a smart toilet system that tracked their bowel movements", "intervention": "smart toilet sensor monitoring of defecation behavior (stool duration, thickness, timing)", "comparator": "stool consistency type measured by the Bristol Stool Form Scale", "primaryOutcome": "how stool dropping duration and thickness relate to stool consistency (constipation score)", "result": "Stools that took longer than 5 seconds to drop were linked to lower Bristol scores (more constipated), and stool thickness decreased as Bristol scores rose", "resultDirection": "unclear", "quality": "very-low", "qualityWhy": "Only 11 people and 45 bowel movements were studied using a new device, so the findings are preliminary and not yet validated.", "directness": "indirect", "limitations": "Very small number of participants and events, no mention of controlling for diet, hydration, or health conditions, and this is an exploratory technology-validation study rather than a clinical trial.", "followUp": "", "plainFinding": "Slower pooping linked to constipation, not length.", "retracted": false, "expressionOfConcern": false, "hasErratum": false, "url": "https://pubmed.ncbi.nlm.nih.gov/40349171/", "sourceText": "Defecation, a fundamental physiological process, remains underexplored despite its importance in human health. To address this gap, a smart toilet system is developed that enables real-time monitoring of defecation behaviors. Analyzing 45 defecation events from 11 participants, key defecation parameters are identified, including stool dropping duration, stool thickness, and eu-tenesmus interval. Stool dropping duration follows a log-normal distribution, with longer durations (>5 s) linked to lower Bristol Stool Form Scale (BSFS) scores, suggesting constipation (p = 0.008 for BSFS1/2/3 vs BSFS5/6/7). Stool thickness decreases with increasing BSFS scores (p = 5 × 10⁻⁶ for BSFS1/2/3 vs BSFS5/6/7), validating its role as an objective marker for bowel function. Eu-tenesmus is introduced, defined as the interval between the last stool drop and cleansing, averaging 74.8 s. It shows significant gender differences (p = 0.014) but no correlation with stool consistency, suggesting its potential as an independent biomarker for gut health. Defecation behaviors between humans and animals is also compared in detail. Longitudinal monitoring demonstrates the potential for personalized health tracking and dietary recommendations. Furthermore, the feasibility of biometric identification is established using 11 defecation-related parameters, including stool properties and cleansing behavior. These features enable high participant differentiation, supporting non-invasive identity verification.", "provenance": [ { "field": "n", "quote": "Analyzing 45 defecation events from 11 participants" }, { "field": "population", "quote": "Analyzing 45 defecation events from 11 participants" }, { "field": "intervention", "quote": "a smart toilet system is developed that enables real-time monitoring of defecation behaviors" }, { "field": "comparator", "quote": "longer durations (>5 s) linked to lower Bristol Stool Form Scale (BSFS) scores" }, { "field": "primaryOutcome", "quote": "key defecation parameters are identified, including stool dropping duration, stool thickness, and eu-tenesmus interval" }, { "field": "result", "quote": "Stool dropping duration follows a log-normal distribution, with longer durations (>5 s) linked to lower Bristol Stool Form Scale (BSFS) scores, suggesting constipation (p = 0.008 for BSFS1/2/3 vs BSFS5/6/7). Stool thickness decreases with increasing BSFS scores (p = 5 × 10⁻⁶ for BSFS1/2/3 vs BSFS5/6/7)" } ] }, { "id": "pmid:40312033", "pmid": "40312033", "doi": "10.1163/18762891-bja00074", "nctId": null, "pmcid": null, "title": "Effects of Traditional Asian Diet on dietary fibre requirement, gut microbiome composition, and faecal and urine metabolomes in healthy Asian women: a pilot study", "firstAuthor": "Sahran", "multipleAuthors": true, "journal": "Benef Microbes", "year": 2025, "design": "rct", "n": 22, "nField": "reported", "population": "healthy Asian women", "intervention": "Traditional Asian Diet (high fibre diet program)", "comparator": "control diet", "primaryOutcome": "meeting fibre needs, gut microbiome, faecal/urine chemicals, and stool form", "result": "higher fibre intake, lower fat intake, and better stool form with the Traditional Asian Diet compared to control", "resultDirection": "benefit", "quality": "low", "qualityWhy": "This was a very small, short, pilot trial (11 per group over 4 weeks), so its findings are not very reliable on their own.", "directness": "indirect", "limitations": "Small pilot study with only 11 participants per group, short 4-week duration, and only healthy women studied, so findings may not generalize.", "followUp": "four-week", "plainFinding": "High-fibre diet improved stool form", "retracted": false, "expressionOfConcern": false, "hasErratum": false, "url": "https://pubmed.ncbi.nlm.nih.gov/40312033/", "sourceText": "The Traditional Asian Diet (TAD) is characterised by high dietary fibre and functional foods. This study investigated TAD's effects on meeting fibre requirements, gut microbiome, and faecal and urine metabolomes. A four-week randomised controlled trial was conducted among healthy Asian women allocated into the TAD group (n = 11) following a newly developed TAD program and the control group (n = 11). Assessments included dietary intake, gut health (symptoms, faecal form, frequency), serum fatty acids binding protein-2 (FABP-2) levels, faecal microbiome via 16s rRNA sequencing, and faecal and urine metabolites which were analysed using gas chromatography-mass spectrometry (GC-MS) and nuclear magnetic resonance (NMR), respectively. The TAD group showed significant increases in dietary fibre ( P < 0.001), reduced fat ( P < 0.05), and improved faecal form ( P = 0.009) compared to the control group. The TAD group was enriched with Parabacteroides merdae, while Bacteroides uniformis was more abundant in the control group. Individuals with baseline Prevotella copri showed its enrichment following TAD and higher butyrate levels, unlike the control group. The TAD led to lower urine levels of creatinine, dimethylamine, and phenethylamine compared to the control diet. In conclusion, the TAD program has proven beneficial effects in achieving dietary fibre, enriching the beneficial microbiota and metabolites, reducing harmful metabolites, and improving faecal form compared to a control diet. Clinical trial registration: NCT04885959, clinicaltrials.gov.", "provenance": [ { "field": "n", "quote": "TAD group (n = 11) following a newly developed TAD program and the control group (n = 11)" }, { "field": "population", "quote": "healthy Asian women" }, { "field": "intervention", "quote": "Traditional Asian Diet (TAD)" }, { "field": "comparator", "quote": "control group" }, { "field": "primaryOutcome", "quote": "This study investigated TAD's effects on meeting fibre requirements, gut microbiome, and faecal and urine metabolomes." }, { "field": "result", "quote": "The TAD group showed significant increases in dietary fibre ( P < 0.001), reduced fat ( P < 0.05), and improved faecal form ( P = 0.009) compared to the control group." } ] }, { "id": "pmid:39697209", "pmid": "39697209", "doi": "10.3389/fmed.2024.1473847", "nctId": null, "pmcid": "PMC11652177", "title": "Efficacy of acupuncture for functional constipation in elderly: a systematic review and meta-analysis", "firstAuthor": "Song", "multipleAuthors": true, "journal": "Front Med (Lausanne)", "year": 2024, "design": "meta-analysis", "n": 469, "nField": "reported", "population": "elderly people with functional constipation", "intervention": "acupuncture treatment for constipation", "comparator": "control group (standard care/medication)", "primaryOutcome": "treatment effectiveness and bowel movement measures (e.g., complete spontaneous bowel movements, Bristol Stool Scale, Clinic Constipation Score)", "result": "Acupuncture improved some constipation measures (treatment effectiveness, complete spontaneous bowel movements, Bristol Stool Scale, CCS) but showed no significant difference in spontaneous bowel movements, Defecation Difficulty Score, or PAC-QOL", "resultDirection": "mixed", "quality": "low", "qualityWhy": "The authors themselves state the evidence is low-to-moderate quality and call for more high-quality research.", "directness": "indirect", "limitations": "Small number of trials (8 RCTs, 469 participants) with mixed outcome significance and author-acknowledged low-to-moderate quality evidence.", "followUp": "", "plainFinding": "Mixed results for constipation relief.", "retracted": false, "expressionOfConcern": false, "hasErratum": false, "url": "https://pubmed.ncbi.nlm.nih.gov/39697209/", "sourceText": "BACKGROUND: Numerous clinical studies have shown that patients suffering from functional constipation can benefit by combining medication with acupuncture. There have been no published reviews or meta-analyses regarding the use of acupuncture in treating functional constipation in older adults. Therefore, we carried out a meta-analysis to assess the impact of acupuncture on elderly patients dealing with functional constipation. METHODS: This study retrieved randomized controlled trials (RCTs) on acupuncture therapy for functional constipation in the elderly from several electronic databases, including Embase, PubMed, Cochrane Library, Wanfang Database, Chinese BioMedical Literature Database, and China National Knowledge Infrastructure. In these databases, clinical investigators evaluated the effectiveness of acupuncture as a primary treatment for elderly people with functional constipation. The Cochrane Handbook for Systematic Reviews of Interventions was used by researchers to evaluate the quality of the study. RESULTS: A total of 469 elderly individuals were included in 8 RCTs. The meta-analysis yielded compelling findings: the application of acupuncture has significantly elevated the rates of treatment effectiveness compared to the control group. Compared with the control group, the treatment group exhibited a statistically significant difference in complete spontaneous bowel movements after treatment. The two groups showed no significant difference in spontaneous bowel movements. However, there was a significant difference in the Bristol Stool Scale scores. The Defecation Difficulty Score and Patient Assessment of Constipation Quality of Life (PAC-QOL) showed p-values that indicated no significant effect. However, acupuncture improved bowel movements, demonstrating a significant difference in the Clinic Constipation Score (CCS) when comparing the two groups. The Nitric Oxide Synthase (NOS) and 5-Hydroxytryptamine (5-HT) contents changed significantly after intervention in both groups. An article reported that the improvement of traditional Chinese medicine (TCM) symptom scores was better in the treatment group than in the control group. CONCLUSION: The analysis results indicated that acupuncture can be beneficial for elderly people with functional constipation; however, strong and comprehensive data are not yet obtainable. Given that our study is based on evidence that is of a low-to-moderate quality, further high-quality research is necessary to enhance the feasibility and practicability of this treatment. SYSTEMATIC REVIEW REGISTRATION: https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42024533215.", "provenance": [ { "field": "n", "quote": "A total of 469 elderly individuals were included in 8 RCTs." }, { "field": "population", "quote": "elderly patients dealing with functional constipation" }, { "field": "intervention", "quote": "the application of acupuncture has significantly elevated the rates of treatment effectiveness compared to the control group" }, { "field": "comparator", "quote": "Compared with the control group, the treatment group exhibited a statistically significant difference in complete spontaneous bowel movements after treatment." }, { "field": "primaryOutcome", "quote": "the treatment group exhibited a statistically significant difference in complete spontaneous bowel movements after treatment" }, { "field": "result", "quote": "The two groups showed no significant difference in spontaneous bowel movements. However, there was a significant difference in the Bristol Stool Scale scores." }, { "field": "result", "quote": "The Defecation Difficulty Score and Patient Assessment of Constipation Quality of Life (PAC-QOL) showed p-values that indicated no significant effect." } ] }, { "id": "pmid:39543202", "pmid": "39543202", "doi": "10.1038/s41598-024-78779-4", "nctId": null, "pmcid": "PMC11564695", "title": "Impact of L-carnitine supplementation on gastric emptying and bowel function in pediatric ketogenic diet therapy: a clinical trial", "firstAuthor": "Nassar", "multipleAuthors": true, "journal": "Sci Rep", "year": 2024, "design": "rct", "n": 30, "nField": "reported", "population": "children aged 12 months to 18 years with drug-resistant epilepsy starting a ketogenic diet", "intervention": "ketogenic diet plus L-carnitine supplement", "comparator": "ketogenic diet without L-carnitine", "primaryOutcome": "stomach emptying speed (measured as antral length) and bowel habits", "result": "L-carnitine group had longer antral length, better stool consistency scores, and more frequent bowel movements than the diet-only group", "resultDirection": "benefit", "quality": "low", "qualityWhy": "Very small trial (30 children) over just 3 months in a specific epilepsy population, not patients with everyday constipation or stool-size concerns.", "directness": "indirect", "limitations": "Small sample size, short 3-month duration, and population limited to children with drug-resistant epilepsy on a strict ketogenic diet rather than general bowel complaints.", "followUp": "3 months", "plainFinding": "More frequent, easier bowel movements.", "retracted": false, "expressionOfConcern": false, "hasErratum": false, "url": "https://pubmed.ncbi.nlm.nih.gov/39543202/", "sourceText": "Ketogenic diet (KD) is an excess fat, enough protein, and minimal carbohydrate diet. The high fat content in KD lowers the oesophageal sphincter tone, slows gastric emptying, and decreases intestinal transit time. The primary aim of the current clinical trial was to study the effect of L-carnitine supplementation on gastric emptying in children with drug resistant epilepsy (DRE) on KD. Assessment of the protective effect of L-carnitine on bowel function and habits in those patients was a secondary aim. The current study recruited 30 patients aged 12 months to 18 years newly diagnosed with DRE assigned to start KD who were following up at the Pediatric Clinical Nutrition and Neurology Outpatient Clinics or were admitted due to DRE at the Pediatric Neurology Inpatient Department, Children's Hospital, Ain Shams University (Egypt). Participants were assigned randomly into 2 arms; arm I: received KD with L-carnitine supplementation, arm II: received KD only. Patients were assessed at baseline and after 3 months of starting KD, the assessments of children included: 24-hour dietary recall, Chalfont Seizures Severity Scale, gastrointestinal symptoms score and Bristol stool chart, frequency of defecation per week, anthropometric measurements assessment, fasting serum lipid profile and measurement of the antral length by ultrasound. There was significant increase in antral length in the patients who received KD with L-carnitine supplementation compared to the non-supplemented group. The antral length showed a significant negative correlation with GI symptoms score in all cases and the L-carnitine supplemented group. It also showed a significant positive correlation with Bristol stool score in all patients and a significant positive correlation with stool frequency in the L-carnitine supplemented group only. L-carnitine supplementation to children with DRE on KD has a significant role in improving gastric motility and it increases the frequency of defecation. Further studies are recommended to explore additional benefits, meanwhile it is prudent to advise L-carnitine supplementation for such patients.", "provenance": [ { "field": "n", "quote": "The current study recruited 30 patients aged 12 months to 18 years" }, { "field": "population", "quote": "newly diagnosed with DRE assigned to start KD who were following up at the Pediatric Clinical Nutrition and Neurology Outpatient Clinics" }, { "field": "intervention", "quote": "arm I: received KD with L-carnitine supplementation" }, { "field": "comparator", "quote": "arm II: received KD only" }, { "field": "primaryOutcome", "quote": "The primary aim of the current clinical trial was to study the effect of L-carnitine supplementation on gastric emptying" }, { "field": "result", "quote": "There was significant increase in antral length in the patients who received KD with L-carnitine supplementation compared to the non-supplemented group." }, { "field": "result", "quote": "L-carnitine supplementation to children with DRE on KD has a significant role in improving gastric motility and it increases the frequency of defecation." }, { "field": "followUp", "quote": "Patients were assessed at baseline and after 3 months of starting KD" } ] }, { "id": "pmid:39214074", "pmid": "39214074", "doi": "10.1093/ismejo/wrae168", "nctId": null, "pmcid": "PMC11406467", "title": "Interplay between particle size and microbial ecology in the gut microbiome", "firstAuthor": "Letourneau", "multipleAuthors": true, "journal": "ISME J", "year": 2024, "design": "lab", "n": 76, "nField": "reported", "population": "76 people who gave stool samples, plus germ-free and antibiotic-treated mice and human fecal microbiota used in lab cultures", "intervention": "a behavioral program to make 41 volunteers chew their food more, plus lab experiments with mouse gut microbiomes and human stool bacteria grown outside the body", "comparator": "people before vs after the chewing intervention, germ-free/antibiotic-treated mice vs normally colonized mice, and different human stool-bacteria donors in lab culture", "primaryOutcome": "the size of particles found in feces (fecal particle size)", "result": "Fecal particle size varied a lot between people but was not changed by better chewing or by diet; it was linked instead to gut transit time and to the mix of gut bacteria, and mice without gut bacteria had larger fecal particles than mice with normal bacteria", "resultDirection": "unclear", "quality": "low", "qualityWhy": "the human findings are mostly correlations from a modest number of people, and the clearest cause-and-effect evidence comes from mouse and lab-dish experiments rather than from people's actual bowel movements.", "directness": "indirect", "limitations": "human associations are correlational, chewing intervention did not change outcome, mechanistic evidence relies on mouse and ex vivo models rather than direct human testing", "followUp": "", "plainFinding": "Gut bacteria shape food particle size.", "retracted": false, "expressionOfConcern": false, "hasErratum": false, "url": "https://pubmed.ncbi.nlm.nih.gov/39214074/", "sourceText": "Physical particles can serve as critical abiotic factors that structure the ecology of microbial communities. For non-human vertebrate gut microbiomes, fecal particle size (FPS) has been known to be shaped by chewing efficiency and diet. However, little is known about what drives FPS in the human gut. Here, we analyzed FPS by laser diffraction across a total of 76 individuals and found FPS to be strongly individualized. Contrary to our initial hypothesis, a behavioral intervention with 41 volunteers designed to increase chewing efficiency did not impact FPS. Dietary patterns could also not be associated with FPS. Instead, we found evidence that human and mouse gut microbiomes shaped FPS. Fecal samples from germ-free and antibiotic-treated mice exhibited increased FPS relative to colonized mice. In humans, markers of longer transit time were correlated with smaller FPS. Gut microbiota diversity and composition were also associated with FPS. Finally, ex vivo culture experiments using human fecal microbiota from distinct donors showed that differences in microbiota community composition can drive variation in particle size. Together, our results support an ecological model in which the human gut microbiome plays a key role in reducing the size of food particles during digestion. This finding has important implications for our understanding of energy extraction and subsequent uptake in gastrointestinal tract. FPS may therefore be viewed as an informative functional readout, providing new insights into the metabolic state of the gut microbiome.", "provenance": [ { "field": "n", "quote": "we analyzed FPS by laser diffraction across a total of 76 individuals" }, { "field": "population", "quote": "we analyzed FPS by laser diffraction across a total of 76 individuals and found FPS to be strongly individualized" }, { "field": "intervention", "quote": "a behavioral intervention with 41 volunteers designed to increase chewing efficiency did not impact FPS" }, { "field": "comparator", "quote": "Fecal samples from germ-free and antibiotic-treated mice exhibited increased FPS relative to colonized mice" }, { "field": "primaryOutcome", "quote": "fecal particle size (FPS) has been known to be shaped by chewing efficiency and diet" }, { "field": "result", "quote": "Contrary to our initial hypothesis, a behavioral intervention with 41 volunteers designed to increase chewing efficiency did not impact FPS. Dietary patterns could also not be associated with FPS. Instead, we found evidence that human and mouse gut microbiomes shaped FPS." }, { "field": "result", "quote": "In humans, markers of longer transit time were correlated with smaller FPS." } ] }, { "id": "pmid:39064725", "pmid": "39064725", "doi": "10.3390/nu16142282", "nctId": null, "pmcid": "PMC11280028", "title": "Does Microbiome Matter in Chronic Intestinal Failure Due to Type 1 Short Bowel Syndrome in Adults?", "firstAuthor": "Ossola", "multipleAuthors": true, "journal": "Nutrients", "year": 2024, "design": "case-series", "n": 44, "nField": "reported", "population": "adults with short bowel syndrome and chronic intestinal failure (missing part of the small intestine, with a stoma)", "intervention": "gut bacteria (microbiome) composition and diet", "comparator": "none; patients compared to each other based on clinical features", "primaryOutcome": "link between gut bacteria/diet and stomal output or hyperphagia (excessive eating)", "result": "higher levels of certain gut bacteria were linked to more stoma output, and fiber intake was linked to hyperphagia", "resultDirection": "unclear", "quality": "very-low", "qualityWhy": "This is a small observational study of a very specific surgical patient group looking only at correlations, not an experiment, so it can't show cause and effect and doesn't apply to typical stool length questions.", "directness": "indirect", "limitations": "Observational and correlational design, no control group, specific to patients with surgically short bowels and stomas rather than general bowel function.", "followUp": "", "plainFinding": "Not relevant to normal stool length.", "retracted": false, "expressionOfConcern": false, "hasErratum": false, "url": "https://pubmed.ncbi.nlm.nih.gov/39064725/", "sourceText": "The exact microbiome composition and function of patients with Short Bowel Syndrome (SBS) and Chronic Intestinal Failure (CIF) are still unknown. Patients with type I SBS-CIF (end-jejunostomy/ileostomy) are little represented in available studies. The aim of this study is to evaluate the microbiome characteristics of adult type 1 SBS-CIF patients according to their clinical features. Fecal microbiota was studied by amplicon-based sequencing and volatile organic compounds (VOCs) were assessed by solid-phase microextraction and gas chromatography-mass spectrometry. A total of 44 adult type 1 SBS-CIF patients were enrolled. At the family level, Lactobacillaceae (38% of the relative frequency) and Streptococcaceae (24%) were predominant; at the genus level, Streptococcus (38% of the relative frequency) and Lactobacillus (24%) were the dominant amplicon sequence variants (ASVs). Patients with increased stomal output showed higher ASVs for Lactobacillus (Rho = +0.38; p = 0.010), which was confirmed after adjusting for small bowel length (OR = 1.04; 95% CI 1.01-1.07, p = 0.023). Hyperphagia was associated with higher concentrations of short-chain fatty acid (SCFA) esters, such as butanoic acid ethyl ester (p = 0.005) and hexanoic acid ethyl ester (p = 0.004). Dietary fiber intake was directly correlated with most VOCs. Hyperphagia was associated with dietary fiber, after adjusting for small bowel length (OR = 1.35; 95% CI 1.01-1.81; p = 0.040). In type 1 SBS-CIF patients, a greater frequency of Lactobacilli was associated with increased stomal outputs, while increased fiber intake and concentrations of SCFA esters were associated with hyperphagia. These results might have implications for clinical practice.", "provenance": [ { "field": "population", "quote": "A total of 44 adult type 1 SBS-CIF patients were enrolled." }, { "field": "intervention", "quote": "Fecal microbiota was studied by amplicon-based sequencing and volatile organic compounds (VOCs) were assessed by solid-phase microextraction and gas chromatography-mass spectrometry." }, { "field": "comparator", "quote": "Patients with increased stomal output showed higher ASVs for Lactobacillus" }, { "field": "primaryOutcome", "quote": "The aim of this study is to evaluate the microbiome characteristics of adult type 1 SBS-CIF patients according to their clinical features." }, { "field": "result", "quote": "Patients with increased stomal output showed higher ASVs for Lactobacillus (Rho = +0.38; p = 0.010), which was confirmed after adjusting for small bowel length (OR = 1.04; 95% CI 1.01-1.07, p = 0.023)." }, { "field": "n", "quote": "A total of 44 adult type 1 SBS-CIF patients were enrolled." } ] }, { "id": "pmid:39051756", "pmid": "39051756", "doi": "10.1002/jsfa.13772", "nctId": null, "pmcid": null, "title": "Effects of Lactocaseibacillus paracasei subsp. paracasei NTU 101 on gut microbiota: a randomized, double-blind, placebo-controlled clinical study", "firstAuthor": "Lin", "multipleAuthors": true, "journal": "J Sci Food Agric", "year": 2024, "design": "rct", "n": null, "nField": "not-reported", "population": "Healthy adults", "intervention": "Probiotic supplement (Lactocaseibacillus paracasei NTU 101, Vigiis 101-LAB)", "comparator": "Placebo", "primaryOutcome": "Gut microbiota composition, bowel movement frequency and stool quality", "result": "Probiotic significantly shifted gut microbiota, improved peristalsis, and shortened time between bowel movements compared to placebo", "resultDirection": "benefit", "quality": "low", "qualityWhy": "Although randomized and placebo-controlled, the abstract does not report how many people were studied or how it measured 'poop length', making it hard to judge reliability.", "directness": "indirect", "limitations": "Abstract does not report participant number, and the study focuses on gut microbiota, peristalsis, and defecation interval rather than stool length specifically", "followUp": "6 weeks", "plainFinding": "Improved bowel regularity, not length", "retracted": false, "expressionOfConcern": false, "hasErratum": false, "url": "https://pubmed.ncbi.nlm.nih.gov/39051756/", "sourceText": "BACKGROUND: Lactocaseibacillus paracasei subsp. paracasei NTU 101 (NTU101) is a well-known commercial probiotic with multiple health beneficial effects. In this study, the gut microbiota modulation effect of an NTU 101 product, Vigiis 101-LAB, on healthy human was investigated in a randomized, double-blind, placebo-controlled human trial. RESULTS: Vigiis 101-LAB significantly modulated human gut microbiota at fourth and sixth weeks of trial (anosim analysis, P = 0.001). It also significantly improved peristalsis (P = 0.003) and shortened defecation interval of subjects. The shift of gut microbiota is significantly fit with defecation interval (P = 0.009) and stool shape (P = 0.001) of subjects. CONCLUSION: Our results suggest that Vigiis 101-LAB promotes human intestinal health with improvement of peristalsis and fecal quality. The gut modulation effects of Vigiis 101-LAB subsequently raised the abundance of vitamin B7, vitamin K, pyrimidine and purine biosynthesis pathways. Vigiis 101-LAB may promote peristalsis via purinergic pathway and possibly conferring prophylactic benefits against irritable bowel syndrome with constipation. © 2024 Society of Chemical Industry.", "provenance": [ { "field": "population", "quote": "gut microbiota modulation effect of an NTU 101 product, Vigiis 101-LAB, on healthy human" }, { "field": "intervention", "quote": "Vigiis 101-LAB" }, { "field": "comparator", "quote": "randomized, double-blind, placebo-controlled" }, { "field": "primaryOutcome", "quote": "gut microbiota modulation effect of an NTU 101 product, Vigiis 101-LAB, on healthy human was investigated" }, { "field": "result", "quote": "Vigiis 101-LAB significantly modulated human gut microbiota at fourth and sixth weeks of trial (anosim analysis, P = 0.001). It also significantly improved peristalsis (P = 0.003) and shortened defecation interval of subjects." } ] }, { "id": "pmid:39032787", "pmid": "39032787", "doi": "10.1016/j.ajcnut.2024.06.025", "nctId": null, "pmcid": "PMC11393394", "title": "Plant-based diet in hyperkalemic chronic kidney disease patients receiving sodium zirconium cyclosilicate: a feasibility clinical trial", "firstAuthor": "Avesani", "multipleAuthors": true, "journal": "Am J Clin Nutr", "year": 2024, "design": "prospective-cohort", "n": 26, "nField": "reported", "population": "adults with stage 4-5 chronic kidney disease and high blood potassium taking a potassium-lowering drug", "intervention": "switching to a high-potassium plant-based diet while continuing the potassium binder", "comparator": "a low-protein, low-potassium diet plus the same potassium binder", "primaryOutcome": "change in stool type and frequency (Bristol stool scale) after diet change", "result": "stool type and frequency did not change after starting the plant-based diet", "resultDirection": "no-benefit", "quality": "low", "qualityWhy": "this was a small, 6-week, non-randomized feasibility trial with only 26 patients and no control group, so it gives weak evidence on stool changes.", "directness": "indirect", "limitations": "Abstract does not mention randomization, blinding, or a separate control group; stool outcome was secondary to the study's main focus on potassium control.", "followUp": "6-wk trial", "plainFinding": "No change in stool pattern.", "retracted": false, "expressionOfConcern": false, "hasErratum": false, "url": "https://pubmed.ncbi.nlm.nih.gov/39032787/", "sourceText": "BACKGROUND: Plant-based diets (PBD) may induce hyperkalemia in chronic kidney disease (CKD) patients. OBJECTIVES: We explored the safety and feasibility of PBD in hyperkalemic CKD patients receiving the potassium binder sodium zirconium cyclosilicate (SZC). METHODS: In the current 6-wk trial, 26 hyperkalemic patients with CKD stage 4-5 not on dialysis received a low-protein low-potassium diet plus SZC for 3 wk and then a PBD with high potassium content delivered as a weekly food basket while continuing SZC for subsequent 3 wk. Plasma potassium was monitored weekly and SZC was titrated to achieve normokalemia. The 24-h urine excretion of potassium and sodium, 24-h food records, dietary quality, nutritional status, Bristol stool scale, Quality of life (QoL), and renal treatment satisfaction were assessed at baseline (week 0), week 3, and week 6. RESULTS: Mean plasma potassium decreased from 5.5 to 4.4 mEq/L within 48-72 h after baseline, then rose to 4.7-5.0 mEq/L throughout the remaining study period following dose adjustments of SZC that matched the increased potassium intake of PBD from week 3 to week 6. Over the study period, 24-h urinary potassium excretion decreased from week 0 to week 3 and increased from week 3 to week 6. During the study, 58% of patients had fasting plasma potassium between 3.5 and 5.0 mEq/L and there was no episode of plasma potassium >6.5 mEq/L or <3.0 mEq/L during the study. P-carbon dioxide increased from baseline until week 6 (21 ± 2 to 23 ± 2 mEq/L; P = 0.002; mean ± SD), whereas remaining laboratory values remained unchanged. Fiber intake, dietary quality, the domain physical functioning from QoL, and 1 question of renal treatment satisfaction improved, whereas stool type and frequency did not change after starting PBD. CONCLUSIONS: PBD in hyperkalemia-prone CKD patients receiving SZC improved dietary quality and increased the intake of healthy foods, whereas plasma potassium concentration remained stable within normal values for most patients. TRIAL REGISTRATION NUMBER: This trial was registered at the https://clinicaltrials.gov/study/NCT04207203 as NCT04207203.", "provenance": [ { "field": "n", "quote": "26 hyperkalemic patients with CKD stage 4-5 not on dialysis" }, { "field": "population", "quote": "hyperkalemic patients with CKD stage 4-5 not on dialysis received a low-protein low-potassium diet plus SZC" }, { "field": "intervention", "quote": "a PBD with high potassium content delivered as a weekly food basket while continuing SZC" }, { "field": "comparator", "quote": "a low-protein low-potassium diet plus SZC for 3 wk" }, { "field": "primaryOutcome", "quote": "Bristol stool scale, Quality of life (QoL), and renal treatment satisfaction were assessed at baseline (week 0), week 3, and week 6" }, { "field": "result", "quote": "stool type and frequency did not change after starting PBD" }, { "field": "followUp", "quote": "6-wk trial" } ] }, { "id": "pmid:38830472", "pmid": "38830472", "doi": "10.1016/j.tjnut.2024.05.028", "nctId": null, "pmcid": "PMC11375456", "title": "Honey Added to Yogurt with Bifidobacterium animalis subsp. lactis DN-173 010/CNCM I-2494 Supports Probiotic Enrichment but Does Not Reduce Intestinal Transit Time in Healthy Adults: A Randomized, Controlled, Crossover Trial", "firstAuthor": "Mysonhimer", "multipleAuthors": true, "journal": "J Nutr", "year": 2024, "design": "rct", "n": 66, "nField": "reported", "population": "healthy adults", "intervention": "yogurt with honey and a probiotic (Bifidobacterium animalis)", "comparator": "heat-treated yogurt plus sugar (and plain yogurt plus sugar)", "primaryOutcome": "how fast food moves through the gut (intestinal transit time)", "result": "Honey yogurt boosted probiotic levels but did not speed up or slow down gut transit time compared to control yogurts", "resultDirection": "no-benefit", "quality": "moderate", "qualityWhy": "It was a well-controlled crossover trial but used healthy adults, not people with bowel symptoms, and was modest in size.", "directness": "indirect", "limitations": "Participants were healthy adults, not people with constipation or long stools, and the extension arm was not randomized.", "followUp": "2 weeks per condition", "plainFinding": "No change in gut transit time.", "retracted": false, "expressionOfConcern": false, "hasErratum": false, "url": "https://pubmed.ncbi.nlm.nih.gov/38830472/", "sourceText": "BACKGROUND: Honey improves probiotic survival in vitro. However, if this effect translates to humans has not been investigated. OBJECTIVES: We aimed to determine effects of honey plus yogurt containing the probiotic Bifidobacterium animalis subsp. lactis DN-173 010/CNCM I-2494 (B. animalis) on intestinal transit time, probiotic enrichment, digestive health, mood, and cognition in adults. METHODS: Sixty-six healthy adults (34 female; 33.6 ± 9.8 y; 24.6 ± 3.0 kg/m2) in a crossover trial were randomly assigned to 2-wk yogurt conditions in a counterbalanced order with ≥4-wk washout: 1) Honey (HON): yogurt plus honey and 2) Negative Control (NC): heat-treated yogurt plus sugar. Of the participants, n = 62 completed the trial, and n = 37 (17 female; 32.0 ± 8.3 y; 25.0 ± 2.9 kg/m2) elected to enroll in a third condition (a nonrandomized study extension) after ≥4-wk washout with a reference Positive Control (PC): yogurt plus sugar. At baseline and end of each of the 3 conditions, intestinal transit time was measured with dye capsules; probiotic abundance with fecal DNA 16S sequencing; digestive health with symptom/function records, Bristol stool consistency, Gastrointestinal Tolerability, and Gastrointestinal Quality of Life Index; mood with Positive and Negative Affect Schedule-Short Form, Depression Anxiety Stress Scales-42, Patient-Reported Outcomes Measurement Information System questionnaires, and an emotional image task; and cognition with a spatial reconstruction task. Data were analyzed using linear mixed-effects models (LMMs) with significance at P ≤ 0.05. Baseline and end data were included in the LMM, with fixed effects being treatment, time, treatment by time interaction, and baseline covariate, and the random effect being the participant. RESULTS: B. animalis was enriched in HON (d = 3.54; P = 0.0002) compared to controls with linear discriminant analysis effect size. Intestinal transit time, gastrointestinal health, mood, and cognition did not differ between conditions (LMM: Ps > 0.05). CONCLUSIONS: Yogurt + honey enriched B. animalis but did not reduce intestinal transit time or have other functional gastrointestinal, mood, or cognitive effects in adults. This trial was registered at www. CLINICALTRIALS: gov as NCT04187950 and NCT04901390.", "provenance": [ { "field": "n", "quote": "Sixty-six healthy adults (34 female; 33.6 ± 9.8 y; 24.6 ± 3.0 kg/m2) in a crossover trial were randomly assigned" }, { "field": "population", "quote": "healthy adults" }, { "field": "intervention", "quote": "yogurt plus honey and" }, { "field": "comparator", "quote": "heat-treated yogurt plus sugar" }, { "field": "primaryOutcome", "quote": "intestinal transit time, probiotic enrichment, digestive health, mood, and cognition" }, { "field": "result", "quote": "Intestinal transit time, gastrointestinal health, mood, and cognition did not differ between conditions" } ] }, { "id": "pmid:38829940", "pmid": "38829940", "doi": "10.1097/MEG.0000000000002786", "nctId": null, "pmcid": null, "title": "Clinical effects of chemical drugs, fecal microbiota transplantation, probiotics, dietary fiber, and acupuncture in the treatment of chronic functional constipation: a systematic review and network meta-analysis", "firstAuthor": "Tan", "multipleAuthors": true, "journal": "Eur J Gastroenterol Hepatol", "year": 2024, "design": "meta-analysis", "n": 17118, "nField": "reported", "population": "adults with chronic functional constipation", "intervention": "fecal microbiota transplantation, probiotics, dietary fiber, or acupuncture", "comparator": "chemical drugs (laxatives) and the treatments compared against each other", "primaryOutcome": "improvement in constipation symptoms, stool form, and quality of life", "result": "fecal microbiota transplantation ranked best for symptom improvement, stool form score, and quality of life, while electroacupuncture had the fewest side effects", "resultDirection": "benefit", "quality": "low", "qualityWhy": "this is a network meta-analysis combining many different trials and treatments indirectly, which makes the comparisons less certain than a single head-to-head trial.", "directness": "indirect", "limitations": "abstract does not report study quality, risk of bias, or heterogeneity across the 45 pooled trials", "followUp": "", "plainFinding": "Fecal transplant most effective for constipation", "retracted": false, "expressionOfConcern": false, "hasErratum": false, "url": "https://pubmed.ncbi.nlm.nih.gov/38829940/", "sourceText": "Currently, there are increasingly diverse treatment modalities for chronic functional constipation (CFC). This study aims to compare the relative efficacy and safety of chemical drugs, fecal microbiota transplantation (FMT), probiotics, dietary fiber, and acupuncture in the treatment of patients with CFC. We searched relevant randomized controlled trials (RCTs) published in five databases up to November 2023. Network meta-analysis (NMA) was carried out using R Studio 4.2.1. Cumulative ranking probability plots, assessed through the surface under the cumulative ranking (SUCRA), were employed to rank the included drugs for various outcome measures. We included a total of 45 RCT studies with 17 118 patients with CFC. From the SUCRA values and NMA results FMT showed the best utility in terms of clinical efficacy, Bristol stool form scale scores, patient assessment of constipation quality of life scores, and the treatment modality with the lowest ranked incidence of adverse effects was electroacupuncture. Subgroup analysis of the chemotherapy group showed that sodium A subgroup analysis of the chemical group showed that sodium picosulfate 10 mg had the highest clinical efficacy. FMT is more promising in the treatment of CFC and may be more effective in combination with the relatively safe treatment of acupuncture.", "provenance": [ { "field": "n", "quote": "17 118 patients with CFC" }, { "field": "population", "quote": "patients with CFC" }, { "field": "intervention", "quote": "chemical drugs, fecal microbiota transplantation (FMT), probiotics, dietary fiber, and acupuncture in the treatment of patients with CFC" }, { "field": "comparator", "quote": "compare the relative efficacy and safety of chemical drugs, fecal microbiota transplantation (FMT), probiotics, dietary fiber, and acupuncture" }, { "field": "primaryOutcome", "quote": "clinical efficacy, Bristol stool form scale scores, patient assessment of constipation quality of life scores" }, { "field": "result", "quote": "FMT showed the best utility in terms of clinical efficacy, Bristol stool form scale scores, patient assessment of constipation quality of life scores, and the treatment modality with the lowest ranked incidence of adverse effects was electroacupuncture" } ] }, { "id": "pmid:38618031", "pmid": "38618031", "doi": "10.5187/jast.2023.e93", "nctId": null, "pmcid": "PMC11007456", "title": "Constipation anti-aging effects by dairy-based lactic acid bacteria", "firstAuthor": "Jaafar", "multipleAuthors": true, "journal": "J Anim Sci Technol", "year": 2024, "design": "animal", "n": null, "nField": "not-reported", "population": "aged rats with drug-induced constipation", "intervention": "dairy-derived probiotic bacteria (Lactobacillus fermentum or Lactobacillus plantarum)", "comparator": "sterile saline control", "primaryOutcome": "stool bulk, softness, moisture, and gut lining changes", "result": "probiotic-treated rats had more and softer stool, higher fecal moisture, and more mucus-producing gut cells than controls", "resultDirection": "benefit", "quality": "low", "qualityWhy": "this is an animal study with an induced constipation model, so it may not reflect how human digestion works, and participant numbers aren't given.", "directness": "indirect", "limitations": "study was done in rats, not humans, and does not address stool length specifically", "followUp": "", "plainFinding": "More stool bulk, softer stool, in rats.", "retracted": false, "expressionOfConcern": false, "hasErratum": false, "url": "https://pubmed.ncbi.nlm.nih.gov/38618031/", "sourceText": "Constipation, which refers to difficulties in defecation and infrequent bowel movement in emptying the gastrointestinal system that ultimately produces hardened fecal matters, is a health concern in livestock and aging animals. The present study aimed to evaluate the potential effects of dairy-isolated lactic acid bacteria (LAB) strains to alleviate constipation as an alternative therapeutic intervention for constipation treatment in the aging model. Rats were aged via daily subcutaneous injection of D-galactose (600 mg/body weight [kg]), prior to induction of constipation via oral administration of loperamide hydrochloride (5 mg/body weight [kg]). LAB strains (L. fermentum USM 4189 or L. plantarum USM 4187) were administered daily via oral gavage (1 × 10 Log CFU/day) while the control group received sterile saline. Aged rats as shown with shorter telomere lengths exhibited increased fecal bulk and soften fecal upon administration of LAB strains amid constipation as observed using the Bristol Stool Chart, accompanied by a higher fecal moisture content as compared to the control (p < 0.05). Fecal water-soluble metabolite profiles showed a reduced concentration of threonine upon administration of LAB strains compared to the control (p < 0.05). Histopathological analysis also showed that the administration of LAB strains contributed to a higher colonic goblet cell count as compared to the control (p < 0.05). The present study illustrates the potential of dairy-sourced LAB strains as probiotics to ameliorate the adverse effect of constipation amid aging, and as a potential dietary intervention strategy for dairy foods including yogurt and cheese.", "provenance": [ { "field": "population", "quote": "Rats were aged via daily subcutaneous injection of D-galactose (600 mg/body weight [kg]), prior to induction of constipation via oral administration of loperamide hydrochloride (5 mg/body weight [kg])" }, { "field": "intervention", "quote": "LAB strains (L. fermentum USM 4189 or L. plantarum USM 4187) were administered daily via oral gavage (1 × 10 Log CFU/day)" }, { "field": "comparator", "quote": "the control group received sterile saline" }, { "field": "primaryOutcome", "quote": "Aged rats as shown with shorter telomere lengths exhibited increased fecal bulk and soften fecal upon administration of LAB strains amid constipation as observed using the Bristol Stool Chart, accompanied by a higher fecal moisture content as compared to the control" }, { "field": "result", "quote": "increased fecal bulk and soften fecal upon administration of LAB strains amid constipation as observed using the Bristol Stool Chart, accompanied by a higher fecal moisture content as compared to the control (p < 0.05)" } ] }, { "id": "pmid:38533644", "pmid": "38533644", "doi": "10.5056/jnm22177", "nctId": null, "pmcid": "PMC11238102", "title": "Consistency of Feces Affects Defecatory Function", "firstAuthor": "Sun", "multipleAuthors": true, "journal": "J Neurogastroenterol Motil", "year": 2024, "design": "lab", "n": 12, "nField": "reported", "population": "healthy adult volunteers (10 analyzed, 4 female/6 male, ages 20-48)", "intervention": "simulated artificial feces of varying hardness inserted into the rectum", "comparator": "different stool consistencies compared to each other (softer vs harder simulated stool)", "primaryOutcome": "measures of defecation such as duration, pressure needed, and shape changes during evacuation", "result": "harder simulated stool took longer and needed more pressure to pass than softer stool, with little difference beyond a certain hardness", "resultDirection": "mixed", "quality": "low", "qualityWhy": "Very small study using artificial stool in healthy volunteers, not real patients or real stool, so it may not reflect everyday bowel habits.", "directness": "indirect", "limitations": "Small sample size, one subject excluded for technical issues, used a mechanical device with simulated (not real) stool in healthy subjects rather than patients.", "followUp": "", "plainFinding": "Harder stool is harder to pass.", "retracted": false, "expressionOfConcern": false, "hasErratum": false, "url": "https://pubmed.ncbi.nlm.nih.gov/38533644/", "sourceText": "BACKGROUND/AIMS: It is a common belief that constipated patients have hard feces that contributes to the difficulties defecating. To the best of our knowledge, no studies had been published on controlled evacuation of simulated feces with different consistencies. METHODS: Twelve normal subjects were recruited for studies with the simulated feces device \"Fecobionics\" of different consistency (silicone shore 0A-40A corresponding to Bristol stool form scale types 2-4). The subjects filled out questionnaires and had the balloon expulsion test and anorectal manometry done for reference. The Fecobionics probes were inserted in rectum in random order with +20 minutes between insertions. The bag was filled to urge-to-defecate and evacuations took place in privacy. Non-parametric statistics with median and quartiles are provided. RESULTS: One subject was excluded due to technical issues, and another had abnormal anorectal manometry-balloon expulsion test. The 4 females/6 males subjects were aged 23 (range 20-48) years. Most differences were observed between the 0A and 10A probe (duration, maximum bag pressure, duration x maximum bag pressure, and relaxation of the front pressure and the bend angle during evacuation), eg, the duration was 9 (8-12) seconds at 0A and 18 (12-21) seconds at 10A (P < 0.05), and maximum bag pressure was 107 (96-116) cmH2O at 0A and 140 (117-162) cmH2O at 10A (P < 0.05). The bend angle before evacuation differed between the probes whereas only the 10A differed from 40A during defecation. The 10A was harder to evacuate than the 0A probe. Except for the bend angles, no further significant change was observed from 10A to 40A. CONCLUSION: Fecal consistency affects defecatory parameters.", "provenance": [ { "field": "population", "quote": "Twelve normal subjects were recruited for studies with the simulated feces device" }, { "field": "n", "quote": "Twelve normal subjects were recruited" }, { "field": "intervention", "quote": "The Fecobionics probes were inserted in rectum in random order with +20 minutes between insertions." }, { "field": "comparator", "quote": "Most differences were observed between the 0A and 10A probe" }, { "field": "primaryOutcome", "quote": "duration, maximum bag pressure, duration x maximum bag pressure, and relaxation of the front pressure and the bend angle during evacuation" }, { "field": "result", "quote": "the duration was 9 (8-12) seconds at 0A and 18 (12-21) seconds at 10A (P < 0.05), and maximum bag pressure was 107 (96-116) cmH2O at 0A and 140 (117-162) cmH2O at 10A (P < 0.05)" } ] }, { "id": "pmid:38470623", "pmid": "38470623", "doi": "10.3390/healthcare12050510", "nctId": null, "pmcid": "PMC10931157", "title": "Probiotics and Prebiotics Affecting Mental and Gut Health", "firstAuthor": "İnce Palamutoglu", "multipleAuthors": true, "journal": "Healthcare (Basel)", "year": 2024, "design": "retrospective", "n": 538, "nField": "reported", "population": "young adults at a Turkish university, mostly female", "intervention": "frequent consumption of probiotic foods like yogurt and ayran", "comparator": "infrequent or no consumption of these foods", "primaryOutcome": "gut symptoms and stool consistency (Gastrointestinal Symptom Rating Scale, Bristol Stool Scale) and mental health scores", "result": "People who never ate yogurt had much higher gut symptom scores, and ayran consumption frequency was linked to stool pattern differences, but prebiotic intake did not significantly affect stool scores", "resultDirection": "mixed", "quality": "low", "qualityWhy": "This is a survey-based study without controlled intervention, so it can only show associations, not prove cause and effect.", "directness": "indirect", "limitations": "Observational survey design, self-reported diet and symptoms, mostly female sample, no mention of stool length specifically.", "followUp": "", "plainFinding": "Yogurt linked to fewer gut symptoms.", "retracted": false, "expressionOfConcern": false, "hasErratum": false, "url": "https://pubmed.ncbi.nlm.nih.gov/38470623/", "sourceText": "The effects of the gut microbiota on mental and intestinal health are an area of great interest. This study aimed to reveal the relationship between the intake of probiotic and prebiotic foods and mental and gut health. Data were obtained using an online survey from young adults (n = 538) enrolled at Afyonkarahisar Health Sciences University who agreed to participate in this study in the 2022-2023 academic year. This study included 538 participants, mostly (85.5%) females. Participants who never consumed yogurt had 7.614 times higher Gastrointestinal Symptom Rating Scale scores than those who consumed yogurt daily (p < 0.01). Similarly, the frequency of ayran consumption had a statistically significant effect on Bristol Stool Scale scores (p < 0.05). The ratio of normal defecation to constipation was 68.7% lower in participants who consumed ayran daily, whereas the ratio of diarrhea to constipation was 76.4% lower in participants who never consumed ayran. However, the frequency of prebiotic consumption did not have a significant effect on Bristol Stool Scale scores (p > 0.05). The consumption of probiotic and prebiotic foods exerted a significant effect on GSRS total scores and subfactors of the Depression Anxiety Stress Scale-42, namely depression, anxiety, and stress.", "provenance": [ { "field": "population", "quote": "Data were obtained using an online survey from young adults (n = 538) enrolled at Afyonkarahisar Health Sciences University who agreed to participate in this study in the 2022-2023 academic year." }, { "field": "n", "quote": "This study included 538 participants, mostly (85.5%) females." }, { "field": "intervention", "quote": "Participants who never consumed yogurt had 7.614 times higher Gastrointestinal Symptom Rating Scale scores than those who consumed yogurt daily (p < 0.01)." }, { "field": "comparator", "quote": "Participants who never consumed yogurt had 7.614 times higher Gastrointestinal Symptom Rating Scale scores than those who consumed yogurt daily (p < 0.01)." }, { "field": "primaryOutcome", "quote": "Similarly, the frequency of ayran consumption had a statistically significant effect on Bristol Stool Scale scores (p < 0.05)." }, { "field": "result", "quote": "However, the frequency of prebiotic consumption did not have a significant effect on Bristol Stool Scale scores (p > 0.05)." } ] }, { "id": "pmid:38464992", "pmid": "38464992", "doi": "10.1253/circrep.CR-23-0099", "nctId": null, "pmcid": "PMC10920016", "title": "Open-Label, Single-Center, Single-Arm Study Evaluating the Efficacy and Safety of Elobixibat for Chronic Constipation in Patients With Heart Failure", "firstAuthor": "Fujisue", "multipleAuthors": true, "journal": "Circ Rep", "year": 2024, "design": "case-series", "n": 18, "nField": "reported", "population": "heart failure patients with chronic constipation", "intervention": "elobixibat 10 mg/day for 12 weeks", "comparator": "baseline measurements before treatment (no control group)", "primaryOutcome": "frequency of spontaneous bowel movements, stool consistency, and straining during defecation", "result": "straining during defecation and cholesterol levels improved significantly, but bowel movement frequency did not significantly increase", "resultDirection": "mixed", "quality": "low", "qualityWhy": "This was a small, single-arm study with only 18 patients and no comparison group, so it's hard to know if the treatment itself caused the changes.", "directness": "indirect", "limitations": "single-center, single-arm design with no control group, small sample size of 18 patients", "followUp": "12 weeks", "plainFinding": "Less straining, lower cholesterol; stool length not studied.", "retracted": false, "expressionOfConcern": false, "hasErratum": false, "url": "https://pubmed.ncbi.nlm.nih.gov/38464992/", "sourceText": "Background: Neither the efficacy nor safety of elobixibat has been investigated in the treatment of chronic constipation in patients with heart failure (HF). Methods and Results: In this prospective, single-center, single-arm study elobixibat (10 mg/day) was administered for 12 weeks to 18 HF patients with chronic constipation defined according to the Rome IV criteria. Spontaneous bowel movement (SBM), stool consistency as measured by the Bristol Stool Form Scale, and degree of straining during defecation were recorded. In addition, biomarkers, blood pressure (BP) measured by ambulatory monitoring, and adverse events were assessed. Although there was no significant difference, the frequency of SBM increased by 2.0/week from baseline to Week 12. Both the degree of straining during defecation and low-density lipoprotein cholesterol (LDL-C) levels were significantly decreased at Week 12 (straining, -0.79 [95% confidence interval (CI), -1.40 to -0.17]; LDL-C, -10.4 mg/dL [95% CI, -17.9 to -2.9]). Although not significant, the difference in BP before and after defecation tended to decrease from baseline by approximately 10 mmHg at Week 12. Serious adverse events were not observed. Conclusions: Elobixibat reduced the degree of straining during defecation, and improved the lipid profile in HF patients with chronic constipation.", "provenance": [ { "field": "n", "quote": "administered for 12 weeks to 18 HF patients with chronic constipation" }, { "field": "population", "quote": "chronic constipation in patients with heart failure (HF)" }, { "field": "intervention", "quote": "elobixibat (10 mg/day) was administered for 12 weeks" }, { "field": "comparator", "quote": "single-center, single-arm study" }, { "field": "primaryOutcome", "quote": "Spontaneous bowel movement (SBM), stool consistency as measured by the Bristol Stool Form Scale, and degree of straining during defecation were recorded" }, { "field": "result", "quote": "Although there was no significant difference, the frequency of SBM increased by 2.0/week from baseline to Week 12. Both the degree of straining during defecation and low-density lipoprotein cholesterol (LDL-C) levels were significantly decreased at Week 12" } ] }, { "id": "pmid:38455871", "pmid": "38455871", "doi": "10.3389/fnut.2023.1254712", "nctId": null, "pmcid": "PMC10917986", "title": "The differential effect of two cereal foods on gut environment: a randomized, controlled, double-blind, parallel-group study", "firstAuthor": "Yamauchi", "multipleAuthors": true, "journal": "Front Nutr", "year": 2023, "design": "rct", "n": null, "nField": "not-reported", "population": "People eating cereal-based foods as part of their diet", "intervention": "Fruit granola or corn flakes eaten daily for 4 weeks", "comparator": "Fruit granola group compared with corn flakes group", "primaryOutcome": "Changes in bowel movements, gut bacteria, and gut immune markers", "result": "Defecation frequency improved, and the two cereal foods affected gut bacteria differently", "resultDirection": "benefit", "quality": "low", "qualityWhy": "It was a small, double-blind trial but did not report participant numbers and measured bowel frequency and gut bacteria, not stool length.", "directness": "indirect", "limitations": "Abstract does not state number of participants and focuses on bowel frequency and microbiome, not stool size or length.", "followUp": "4 weeks", "plainFinding": "More frequent bowel movements with fiber cereal.", "retracted": false, "expressionOfConcern": false, "hasErratum": false, "url": "https://pubmed.ncbi.nlm.nih.gov/38455871/", "sourceText": "BACKGROUND AND AIMS: Cereal-based foods such as fruit granola (FG) and corn flakes (CF) form part of a fiber-rich diet. Dietary fiber has a good effect on human health. However, changes in gut microbiota and intestinal immunity have not been investigated. We conducted a randomized, double-blind, placebo-controlled trial to investigate the effects of FG and CF intake on gut microbiota, metabolome, and the immune system. METHODS: Subjects continuously consume CF or FG for 4 weeks. Stool samples, and questionnaires on defecation were collected before, 2 weeks after, and 4 weeks after intake. Gut microbiota was analyzed using 16S rRNA gene amplicon sequencing. Fecal metabolomes were analyzed using GC/MS and CE-TOF/MS. Fecal IgA was analyzed using ELISA. RESULTS: The defecation frequency after cereal based food intake was improved. The different cereal-based foods had different effects on gut microbiome. The increase in intestinal IgA levels was positively correlated with the relative abundance of Dialister and the Lachnospiraceae ND3007 group in CF and FG group, respectively. SCFAs showed a positive correlation with Prevotella 9 in the FG group. CONCLUSION: This study showed that the supplement in dietary fiber contained in CF and FG improves bowel movements. CF and FG each had different effects on gut microbes, metabolites and different relationships between fecal IgA or SCFAs and gut microbiota.", "provenance": [ { "field": "population", "quote": "Subjects continuously consume CF or FG for 4 weeks." }, { "field": "intervention", "quote": "Cereal-based foods such as fruit granola (FG) and corn flakes (CF)" }, { "field": "comparator", "quote": "The different cereal-based foods had different effects on gut microbiome." }, { "field": "primaryOutcome", "quote": "Stool samples, and questionnaires on defecation were collected before, 2 weeks after, and 4 weeks after intake." }, { "field": "result", "quote": "The defecation frequency after cereal based food intake was improved." } ] }, { "id": "pmid:38173161", "pmid": "38173161", "doi": "10.5056/jnm21091", "nctId": null, "pmcid": "PMC10774807", "title": "Relationship Between Colonic Transit Response to Eating With Self-reported Constipation Severity in Constipated Patients According to the Phenotype", "firstAuthor": "Deutsch", "multipleAuthors": true, "journal": "J Neurogastroenterol Motil", "year": 2024, "design": "prospective-cohort", "n": 387, "nField": "reported", "population": "adult outpatients with chronic constipation (IBS-C, functional constipation, or defecation disorders)", "intervention": "colonic transit response to eating (CTRE), measured by colonic transit time testing", "comparator": "differences between constipation subtypes (IBS-C, FC, DD)", "primaryOutcome": "relationship between colonic transit response to eating and self-reported constipation severity", "result": "Constipation severity was linked to total colon transit time and bloating in IBS-C and FC, but only linked to how the colon responded to eating (left CTRE) in FC and defecation disorder patients, not in IBS-C", "resultDirection": "mixed", "quality": "low", "qualityWhy": "This is an observational study of one group of patients with no comparison to healthy people or treatment, so it can only show associations, not prove what causes long or large stools.", "directness": "indirect", "limitations": "Abstract does not mention control group, blinding, or adjustment for confounders; study is cross-sectional so cause and effect cannot be determined.", "followUp": "", "plainFinding": "Transit speed tied to severity, varies by type.", "retracted": false, "expressionOfConcern": false, "hasErratum": false, "url": "https://pubmed.ncbi.nlm.nih.gov/38173161/", "sourceText": "BACKGROUND/AIMS: Eating is the major synchronizer of gastrointestinal motility and secretions. The present study aims to evaluate the interplay between self-perceived constipation severity (CS) and colonic response to eating in constipated patients according to the phenotype. METHODS: We included 387 consecutive outpatients complaining of Rome IV chronic idiopathic constipation. Likert scales for CS, abdominal pain severity, bloating severity, depression and anxiety assessment, total and segmental colonic transit time (CTT), and colonic transit response to eating (CTRE) were performed in all patients. RESULTS: Of the 387 patients included (49.7 ± 16.4 years), 320 (83%) were female, 203 had irritable bowel syndrome with constipation (IBS-C), 184 as functional constipation (FC), and 283 had defecation disorders (DD). The female gender was characterized by increased bloating severity (P = 0.011) and decreased Bristol stool form (P = 0.002). In IBS-C and FC patients, CS was related with bloating severity (P < 0.001 in both groups) and total CTT (P = 0.007 in IBS-constipation, P = 0.040 in FC). In IBS-C patients, CS was also associated with abdominal pain severity (P = 0.003) and Bristol stool form (P = 0.004). In contrast, in FC, CS was only related to left CTRE (P = 0.006), and in patients with DD, CS was associated with total CTT (P < 0.001) and left CTRE (P = 0.002). CONCLUSION: Colonic transit response to eating was not associated to CS in IBS-C patients, but left CTRE was associated with constipation severity in FC and DD patients.", "provenance": [ { "field": "n", "quote": "We included 387 consecutive outpatients complaining of Rome IV chronic idiopathic constipation." }, { "field": "population", "quote": "Of the 387 patients included (49.7 ± 16.4 years), 320 (83%) were female, 203 had irritable bowel syndrome with constipation (IBS-C), 184 as functional constipation (FC), and 283 had defecation disorders (DD)." }, { "field": "intervention", "quote": "total and segmental colonic transit time (CTT), and colonic transit response to eating (CTRE) were performed in all patients" }, { "field": "comparator", "quote": "203 had irritable bowel syndrome with constipation (IBS-C), 184 as functional constipation (FC), and 283 had defecation disorders (DD)" }, { "field": "primaryOutcome", "quote": "The present study aims to evaluate the interplay between self-perceived constipation severity (CS) and colonic response to eating in constipated patients according to the phenotype." }, { "field": "result", "quote": "In contrast, in FC, CS was only related to left CTRE (P = 0.006), and in patients with DD, CS was associated with total CTT (P < 0.001) and left CTRE (P = 0.002)." }, { "field": "result", "quote": "Colonic transit response to eating was not associated to CS in IBS-C patients, but left CTRE was associated with constipation severity in FC and DD patients." } ] }, { "id": "pmid:37926855", "pmid": "37926855", "doi": "10.1186/s40168-023-01691-y", "nctId": null, "pmcid": "PMC10626715", "title": "Gut microbiota response to in vitro transit time variation is mediated by microbial growth rates, nutrient use efficiency and adaptation to in vivo transit time", "firstAuthor": "Minnebo", "multipleAuthors": true, "journal": "Microbiome", "year": 2023, "design": "lab", "n": 6, "nField": "reported", "population": "stool bacteria samples from six people with short, medium or long gut transit times", "intervention": "growing those gut bacteria in an artificial gut model set to different transit speeds (21, 32 or 63 hours)", "comparator": "the same bacteria samples grown at the other transit speeds", "primaryOutcome": "changes in bacterial growth, species makeup and the chemicals (short-chain fatty acids) they produce", "result": "transit time was the biggest factor changing bacterial growth and the mix of species; slower transit increased some fibre-digesting bacteria and overall short-chain fatty acid output, while faster transit let bacteria convert carbs to biomass more efficiently", "resultDirection": "mixed", "quality": "very-low", "qualityWhy": "this was a small lab experiment using an artificial gut model with only six stool donors, not a study of people or of stool size itself", "directness": "indirect", "limitations": "in vitro artificial gut model, only six donors, does not measure stool size or volume at all", "followUp": "", "plainFinding": "Slower gut transit changes bacteria, raises fermentation.", "retracted": false, "expressionOfConcern": false, "hasErratum": false, "url": "https://pubmed.ncbi.nlm.nih.gov/37926855/", "sourceText": "BACKGROUND: Transit time is an important modulator of the human gut microbiome. The inability to modify transit time as the sole variable hampers mechanistic in vivo microbiome research. We singled out gut transit time in an unprecedented in vitro approach by subjecting faecal microbial communities from six individuals with either short, medium or long in vivo transit times, to three different colonic transit times of 21, 32 and 63 h in the validated human gut in vitro model, SHIME. RESULTS: Transit time was identified as the single most important driver of microbial cell concentrations (52%), metabolic activity (45%) and quantitative (24%) and proportional (22%) community composition. Deceleration of transit was characterised by a significant decrease of specific Bifidobacterium and Veillonella spp. and increase of specific fibre degrading bacteria and nutrient specialists, such as Bacteroides, Prevotella, Ruminococcus, Bilophila and Akkermansia spp. These microbial communities reached a higher population density and net carbohydrate fermentation, leading to an increased SCFA production at longer transit times. In contrast, the carbohydrate-to-biomass production efficiency was increased at shorter transits, particularly in well-adapted faecal microbiomes from donors with short in vivo transit. Said adaptation was also reflected in the carbohydrate-to-SCFA conversion efficiency which varied with donor, but also colon region and SCFA chain length. A long transit time promoted propionate production, whereas butyrate production and butyrate producers were selectively enriched in the proximal colon at medium transit time. CONCLUSION: Microbial growth rates and nutrient utilisation efficiency mediate the species-specific gut microbiota response to in vitro transit time variation, which is the main driver of in vitro microbial load, metabolism and community composition. Given the in vivo transit time variation within and between individuals, the personalisation of in vitro transit time based on in vivo data is required to accurately study intra- and inter-individual differences in gut microbiome structure, functionality and interactions with host and environmental modulators. Video Abstract.", "provenance": [ { "field": "n", "quote": "faecal microbial communities from six individuals" }, { "field": "population", "quote": "faecal microbial communities from six individuals with either short, medium or long in vivo transit times" }, { "field": "intervention", "quote": "three different colonic transit times of 21, 32 and 63 h in the validated human gut in vitro model, SHIME" }, { "field": "comparator", "quote": "three different colonic transit times of 21, 32 and 63 h" }, { "field": "primaryOutcome", "quote": "Transit time was identified as the single most important driver of microbial cell concentrations (52%), metabolic activity (45%) and quantitative (24%) and proportional (22%) community composition." }, { "field": "result", "quote": "These microbial communities reached a higher population density and net carbohydrate fermentation, leading to an increased SCFA production at longer transit times. In contrast, the carbohydrate-to-biomass production efficiency was increased at shorter transits" } ] }, { "id": "pmid:37793306", "pmid": "37793306", "doi": "10.1016/j.ctcp.2023.101801", "nctId": null, "pmcid": null, "title": "Effect of acupressure on alleviating constipation among inpatients with stroke during the acute phase: A randomized controlled trial", "firstAuthor": "Nieh", "multipleAuthors": true, "journal": "Complement Ther Clin Pract", "year": 2023, "design": "rct", "n": 128, "nField": "reported", "population": "hospital patients with acute stroke experiencing constipation", "intervention": "acupressure at three acupoints twice daily for 7 days", "comparator": "sham acupressure", "primaryOutcome": "constipation severity and stool form, measured by Constipation Assessment Scale and Bristol Stool Form Scale", "result": "acupressure group had lower constipation scores, less need for laxatives, and less hard stool over time compared to sham group", "resultDirection": "benefit", "quality": "moderate", "qualityWhy": "it was a randomized trial with a sham control, but it was small and specific to stroke patients, not general constipation.", "directness": "indirect", "limitations": "abstract does not mention blinding of outcome assessors or long-term follow-up beyond the 7-day intervention", "followUp": "7 days", "plainFinding": "Less constipation after stroke.", "retracted": false, "expressionOfConcern": false, "hasErratum": false, "url": "https://pubmed.ncbi.nlm.nih.gov/37793306/", "sourceText": "BACKGROUND AND PURPOSE: This study aimed to explore the effects of acupressure in alleviating constipation among inpatients with stroke in neurological departments. MATERIAL AND METHODS: This was a two-arm, parallel, randomized, controlled trial conducted between September 2020 and August 2021. In total, 128 inpatients with stroke at the acute phase from neurological departments were randomly assigned at a 1:1 ratio to either an acupressure group (ST25, CV12, and CV6) or a sham acupressure group for twice-daily therapy at 4 min per intervention for 7 days. The Bristol Stool Form Scale and Constipation Assessment Scale (CAS) were assessed at the beginning and completion of the study. A generalized estimating equation was used for data analyses. RESULTS: The mean ages were 63.8 ± 19.1 and 66.2 ± 16.0 years, and the average National Institutes of Health Stroke Scale scores were 7.2 ± 5.6 and 8.1 ± 6.3 points for the acupressure and sham acupressure groups, respectively. The acupressure group demonstrated gradually lower scores on the CAS over time than the sham acupressure group. Patients who received acupressure had a lower likelihood of requiring defecation medication and were more likely to have normal bowel movements and a decreased risk of their stool appearing as a hard lump than those who received sham acupressure over time. CONCLUSION: Traditional Chinese medicine-based acupressure can help alleviate constipation and reduce the use of defecation medication among inpatients with stroke who have been admitted to neurological departments. TRIAL AND PROTOCOL REGISTRATION: ClinicalTrials.gov, NCT05612646.", "provenance": [ { "field": "n", "quote": "In total, 128 inpatients with stroke at the acute phase from neurological departments were randomly assigned" }, { "field": "population", "quote": "inpatients with stroke at the acute phase from neurological departments" }, { "field": "intervention", "quote": "acupressure group (ST25, CV12, and CV6) or a sham acupressure group for twice-daily therapy at 4 min per intervention for 7 days" }, { "field": "comparator", "quote": "sham acupressure group" }, { "field": "primaryOutcome", "quote": "The Bristol Stool Form Scale and Constipation Assessment Scale (CAS) were assessed at the beginning and completion of the study." }, { "field": "result", "quote": "The acupressure group demonstrated gradually lower scores on the CAS over time than the sham acupressure group. Patients who received acupressure had a lower likelihood of requiring defecation medication and were more likely to have normal bowel movements and a decreased risk of their stool appearing as a hard lump than those who received sham acupressure over time." } ] } ], "faqs": [ { "q": "Why is my poop so long?", "a": "No study has tested what makes a single stool long. Diet (especially fibre) and how fast food moves through your gut affect stool softness, weight, and frequency, and probably affect its size too, but no study measured length itself. A long stool on its own, with no other symptoms, is not something research has linked to disease." }, { "q": "What does long, thin poop mean?", "a": "Thin stool was described in a small study of people who already had a known narrowing in the bowel after hemorrhoid surgery, and most of them needed a procedure to fix it. No study has tested whether thin stool predicts an undiagnosed narrowing or growth in people without that history, so an occasional thin stool in someone otherwise well hasn't been shown to mean anything concerning." }, { "q": "What happens when you hold your poop too long?", "a": "No study in this review tested delaying a bowel movement and its effect on stool shape or length. Related lab work found that harder stool needs more pressure and time to pass, and that slower transit through the colon changes the gut bacteria that help form stool — but 'holding it in' specifically has not been studied." }, { "q": "Does fibre make your poop longer?", "a": "Fibre has been shown to make stool softer, heavier, and more frequent, and to speed up gut transit in people with normal bowel function. No study measured stool length as an outcome, so whether fibre makes stool specifically longer hasn't been directly tested." }, { "q": "Should I see a doctor about a long stool?", "a": "A single long stool with no other symptoms hasn't been studied as a sign of disease. See a doctor if you notice ongoing changes in bowel habit, persistent thin or pencil-like stool, blood, unexplained weight loss, or pain — these are the situations the available (though indirect) evidence touches on, not stool length by itself." } ], "searchedAs": [ "why is my poop so long", "why is my poop long", "why are my poops so long in length", "what does long thin poop mean", "what happens when you hold your poop too long", "why did my poop come out so long", "why is my poop very long" ], "patientTakeaway": "A long stool by itself, with no other symptoms, has not been studied as a sign of a bowel problem — the research that exists is about treating constipation and gut bacteria, not about why a single stool is long. It most likely reflects normal day-to-day differences in diet, fluid, and gut transit. See a doctor if you also notice persistent thin stool, blood, ongoing changes in your bowel habit, or unexplained weight loss, since those are the situations linked to bowel problems in the studies available.", "methodology": { "databases": [ "PubMed", "ClinicalTrials.gov", "Crossref" ], "searchStrings": { "pubmed": "(\"Feces\"[Mesh] OR stool[tiab] OR stools[tiab]) AND (length[tiab] OR size[tiab] OR caliber[tiab] OR shape[tiab] OR form[tiab] OR \"Bristol stool\"[tiab]) AND (\"Gastrointestinal Transit\"[Mesh] OR transit time[tiab] OR \"Dietary Fiber\"[Mesh] OR fiber intake[tiab] OR defecation[tiab])" }, "pubmedQueryTranslation": "(\"Feces\"[MeSH Terms] OR \"stool\"[Title/Abstract] OR \"stools\"[Title/Abstract]) AND (\"length\"[Title/Abstract] OR \"size\"[Title/Abstract] OR \"caliber\"[Title/Abstract] OR \"shape\"[Title/Abstract] OR \"form\"[Title/Abstract] OR \"Bristol stool\"[Title/Abstract]) AND (\"Gastrointestinal Transit\"[MeSH Terms] OR \"transit time\"[Title/Abstract] OR \"Dietary Fiber\"[MeSH Terms] OR \"fiber intake\"[Title/Abstract] OR \"defecation\"[Title/Abstract])", "searchedOn": "2026-10-13", "inclusion": [ "Human, animal or laboratory studies reporting an outcome relevant to the question" ], "exclusion": [ "Records about a different condition or intervention", "Records reporting no outcome", "Retracted publications, which are listed but excluded from every count" ], "extractionLevel": "abstract", "gradingNote": "Evidence strength is adapted from the GRADE framework. It is not a GRADE assessment and was not produced by a GRADE panel.", "limits": [ "Fields were read from abstracts, not full text, so detail reported only in a paper's methods section is not captured." ] }, "seo": { "title": "Why Is My Poop So Long? What Studies Show", "description": "No study has tested why stool is long or if it signals a problem. See what 34 studies on fibre, transit time, and bowel habits found." }, "lastChecked": "2026-10-13", "lastChanged": "2026-10-13", "nextCheckDue": "2026-11-13", "history": [], "pipeline": { "screenModel": "claude-haiku-4-5", "extractModel": "claude-sonnet-5", "composeModel": "claude-sonnet-5", "promptVersion": "ev-1", "ranOn": "2026-10-13" }, "status": "published" }