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Gut health

Everything in the library studied for it, medical and holistic together. Within each kind, what was shown to help comes first, strongest evidence first. What was tested and not shown to help stays on the list.

Strong several reviews agree · Moderate one review or consistent trials · Limited one or a few small studies · Untested no study in people, listed with what it rests on

Medication27 Peptides and SARMs3 Supplements30 Therapies11 Food and drink4 Diets2 Lab markers1

Medication

H2 blockersStrong

Stress ulcer bleeding in intensive care

Shown to lower clinically important gut bleeding in critically ill patients, about 3 to 5 fewer per 100 at higher bleeding risk, with no clear effect on deaths.

Compared with placebo or no prophylaxis [6][7]; proton pump inhibitors [7]

The numbers and sources

Effect: Against placebo or no prophylaxis, H2 blockers reduced clinically important gut bleeding (OR 0.46, 95% CI 0.27 to 0.79), 4.6% fewer in the highest-risk and 3.1% fewer in high-risk patients, with no effect on mortality (OR 0.96) [6]. An updated analysis found the same direction (RR 0.67, 95% CI 0.48 to 0.94), a larger reduction with proton pump inhibitors than H2 blockers (RR 0.69), and no mortality difference (RR 0.98) [7].
Population: 72 trials with 12,660 patients [6]; 74 trials with 39,569 patients [7].
Sources: [6], [7]
Caveats: Both analyses come from the same research group, and the second updates the first. Results apply to critically ill patients only.

OndansetronStrong

Nausea and vomiting after surgery

Shown to lower vomiting in the 24 hours after surgery by about 45% against placebo, though several other antiemetics and combinations ranked higher.

Compared with placebo [1][2][3]; dexamethasone, droperidol, granisetron, aprepitant and drug combinations, in network comparisons [1]

The numbers and sources

Effect: In a network meta-analysis, ondansetron reduced vomiting within 24 hours against placebo (RR 0.55, 95% CI 0.51 to 0.60, high certainty), ranking 13th of 28 single drugs. Combinations of drugs generally reduced vomiting more [1]. An earlier Cochrane review found eight drugs, ondansetron among them, prevented postoperative nausea and vomiting with relative risks of 0.60 to 0.80, and estimated that where 80 of 100 people would be sick, about 28 benefit from a drug [2]. In two label trials in women, a single 16 mg dose before anesthesia reduced nausea and vomiting more than placebo [3].
Population: 97,516 adults in 585 studies, 246 of them of ondansetron [1]; 103,237 people in 737 studies [2]; 865 women having inpatient surgery [3].
Sources: [1], [2], [3]
Caveats: Most studies were small and 83% of participants were women [1]. The label states no trials of the tablet were done in men [3]. Low doses showed no clinically important benefit [1].

OndansetronStrongStudied in children

Vomiting in children with stomach bugs

Shown to raise the share of children who stopped vomiting and to cut the need for IV fluids by about half against placebo in children with gastroenteritis.

Compared with placebo [4][5][6]

The numbers and sources

Effect: Oral ondansetron raised the share who stopped vomiting (RR 1.34, NNT 5), and lowered IV rehydration in the emergency department (RR 0.41, NNT 5) and immediate hospital admission (RR 0.40, NNT 17) [4]. A later review found fewer oral rehydration failures (RR 0.5, 95% CI 0.37 to 0.69), less IV rehydration (RR 0.45, 95% CI 0.31 to 0.63) and fewer admissions (RR 0.53, 95% CI 0.29 to 0.97), with no difference in vomiting cessation after 4, 24 or 48 hours [5]. A single dose lowered oral rehydration failure (RR 0.43, 95% CI 0.34 to 0.55), IV hydration (RR 0.44, 95% CI 0.34 to 0.57) and hospitalization within 8 hours (RR 0.49, 95% CI 0.32 to 0.75) [6].
Population: 1,020 children in seven trials [4]; 1,215 children in 10 trials [5]; 2,146 children and adolescents in 13 trials [6].
Sources: [4], [5], [6]
Caveats: Return visits to the emergency department did not differ (RR 1.14) [5][6]. Diarrhea was reported as a side effect in four of five ondansetron studies [4].

H2 blockersModerate

Heartburn relief in reflux disease

Shown to relieve heartburn more often than placebo in adults with reflux symptoms, and less often than proton pump inhibitors.

Compared with placebo [1][2]; proton pump inhibitors [1]

The numbers and sources

Effect: In people treated without an endoscopy first, the risk ratio for heartburn remission against placebo was 0.77 (95% CI 0.60 to 0.99) for H2 blockers, a value below 1 favoring the drug. In people with a normal endoscopy it was 0.84 (95% CI 0.74 to 0.95). Proton pump inhibitors did better than H2 blockers (RR 0.66 and 0.78) [1]. In a label trial in reflux without erosions, 82% improved on famotidine 20 mg twice daily, 69% on 40 mg at bedtime and 62% on placebo at 6 weeks [2].
Population: 34 randomized trials of short-term treatment in adults with reflux symptoms [1]; 376 adults with reflux symptoms and no erosions on endoscopy [2].
Sources: [1], [2]
Caveats: Only two placebo-controlled trials of H2 blockers in each group of the review [1]. Famotidine 40 mg at bedtime was not shown to beat placebo in the label trial [2].

H2 blockersModerateVery common

Healing erosive esophagitis

Shown to heal erosive esophagitis more often than placebo, 69% against 29% at 12 weeks on famotidine 40 mg twice daily, but less often than proton pump inhibitors.

Compared with placebo [3][2]; proton pump inhibitors [3]; ranitidine [2]

The numbers and sources

How common: Very common: more than 1 in 10 people.
Effect: H2 blockers healed esophagitis more often than placebo (RR 0.74, 95% CI 0.66 to 0.84, a value below 1 favoring the drug), and proton pump inhibitors healed it more often than H2 blockers (RR 0.51, 95% CI 0.44 to 0.59) [3]. In a US label trial, healing at 12 weeks was 69% on famotidine 40 mg twice daily, 54% on 20 mg twice daily and 29% on placebo. In an international trial, 12-week healing was 71% on famotidine 40 mg twice daily and 60% on ranitidine 150 mg twice daily [2].
Population: 10 trials with 1,241 people comparing H2 blockers with placebo, within a review of 134 trials [3]; 318 adults in the US trial and 440 in the international trial [2].
Sources: [3], [2]
Caveats: Cochrane withdrew the 2007 review in 2011 [3]. Symptom relief did not differ between famotidine and ranitidine [2].

H2 blockersModerateVery common

Healing duodenal and gastric ulcers

Shown to heal more duodenal and gastric ulcers than placebo. In one trial, 83% of duodenal ulcers healed on famotidine by 8 weeks against 45% on placebo.

Compared with placebo [2]

The numbers and sources

How common: Very common: more than 1 in 10 people.
Effect: In a US duodenal ulcer trial, 70% healed by week 4 on famotidine 40 mg at bedtime and 67% on 20 mg twice daily, against 31% on placebo. By week 8, 83% on famotidine and 45% on placebo had healed. In two gastric ulcer trials, 8-week healing was 78% and 80% on famotidine 40 mg at bedtime against 64% and 54% on placebo [2].
Population: 270 adult outpatients with duodenal ulcer, and 149 and 294 adults with gastric ulcer, in double-blind trials [2].
Sources: [2]
Caveats: Label trials. Pain relief at week 8 did not differ from placebo in the gastric ulcer trials, though pain resolved sooner on famotidine [2].

H2 blockersModerateVery common

Keeping duodenal ulcers from returning

Shown to halve duodenal ulcer return over 12 months on famotidine 20 mg at bedtime, 23% against 57% on placebo in one trial and 36% against 76% in another.

Compared with placebo [2]

The numbers and sources

How common: Very common: more than 1 in 10 people.
Effect: In the US trial, cumulative duodenal ulcer recurrence within 12 months was 23% on famotidine and 57% on placebo. In the international trial it was 36% and 76% [2].
Population: 178 and 632 adults with healed duodenal ulcers in two randomized double-blind trials [2].
Sources: [2]
Caveats: Controlled trials did not go beyond one year [2].

H2 blockersModerateCommon

Preventing ulcers in people taking NSAIDs or aspirin

Shown to prevent ulcers in people on NSAIDs or low-dose aspirin. With aspirin, gastric ulcers developed in 3.4% on famotidine against 15.0% on placebo over 12 weeks.

Compared with placebo [4][5]

The numbers and sources

How common: Common: between 1 in 100 and 1 in 10 people.
Effect: In NSAID users, standard-dose H2 blockers reduced endoscopic duodenal ulcers (RR 0.36, 95% CI 0.18 to 0.74) but not gastric ulcers (RR 0.73, 95% CI 0.50 to 1.09). Double-dose H2 blockers reduced gastric ulcers (RR 0.44, 95% CI 0.26 to 0.74) [4]. In people taking low-dose aspirin, at 12 weeks gastric ulcers developed in 3.4% on famotidine and 15.0% on placebo (OR 0.20), duodenal ulcers in 0.5% and 8.5% (OR 0.05), and erosive esophagitis in 4.4% and 19.0% (OR 0.20) [5].
Population: 40 randomized trials of NSAID ulcer prevention [4]; 404 adults taking aspirin 75 to 325 mg a day, without ulcers at the start [5].
Sources: [4], [5]
Caveats: Endoscopic ulcers stand in for bleeding ulcers. In the aspirin trial, 82 people without a final endoscopy were counted as normal [5].

MirtazapineModerate

Nausea and stomach symptoms

Shown to cut nausea and vomiting after surgery by about half against placebo across three trials, with far more sedation.

The numbers and sources

Effect: Mirtazapine given before surgery reduced postoperative nausea and vomiting against placebo (RR 0.44, 95% CI 0.32 to 0.62) and gave rates similar to ondansetron in one trial (RR 0.96, 95% CI 0.48 to 1.94). Sedation was more frequent (RR 22.47, 95% CI 5.61 to 89.93) [8]. In people with functional dyspepsia not helped by standard drugs, 8 weeks of mirtazapine improved dyspepsia symptom scores, including fullness after meals, early satiation, nausea and vomiting, and increased weight against a control group [9]. In depression trials, mirtazapine caused less nausea or vomiting than SSRIs [2].
Population: Three placebo-controlled trials in surgical patients [8]; 120 patients with functional dyspepsia [9]; 2,626 participants in 12 trials against SSRIs [2].
Sources: [8], [9], [2]
Caveats: Not an approved use. Evidence quality for the surgery analysis was rated moderate to low, and the dyspepsia trial was single-center. No trial in chemotherapy nausea or pregnancy nausea was sourced for this page.

OndansetronModerate

Nausea and vomiting with chemotherapy

Shown to prevent vomiting with chemotherapy in controlled trials, with no vomiting over 3 days in 61% on ondansetron against 6% on placebo in one trial.

Compared with placebo [3]; a historical placebo group [3]

The numbers and sources

Effect: In a placebo-controlled trial with a cyclophosphamide and doxorubicin regimen, 61% on ondansetron 8 mg had no vomiting over 3 days, against 6% on placebo, and 21% against 71% had more than 2 episodes or withdrew. With cisplatin regimens, 66% on a single 24 mg dose had no vomiting and no rescue medicine over 24 hours, better than a historical placebo group in which more than 90% vomited [3].
Population: 67 adults in the placebo-controlled trial and 357 adults in the cisplatin trial, as reported in the label [3].
Sources: [3]
Caveats: The cisplatin trials compared with a historical control, not a concurrent placebo group [3].

OndansetronModerate

Irritable bowel syndrome with diarrhea

Shown to firm stools and reduce diarrhea symptoms against placebo in pooled trials, with about 5 treated for one extra stool responder, but not to relieve abdominal pain.

Compared with placebo [8]

The numbers and sources

Effect: In the TRITON trial, 40.5% on ondansetron and 27.9% on placebo met the FDA composite endpoint, a difference that was not significant, while stool consistency improved (adjusted mean difference -0.7). Pooled with two similar trials, ondansetron improved the composite endpoint (RR of not responding 0.86, 95% CI 0.75 to 0.98, NNT 9) and stool response (RR 0.65, 95% CI 0.52 to 0.82, NNT 5), but not abdominal pain response (RR 0.95, 95% CI 0.74 to 1.20) [8].
Population: 80 adults in TRITON over 12 weeks, and 327 in the pooled analysis of three trials [8].
Sources: [8]
Caveats: TRITON recruited 80 of a planned 400 patients [8].

Proton pump inhibitorsModerate

Heartburn relief in reflux disease

Shown to relieve heartburn more often than placebo or H2 blockers in adults with reflux symptoms, with a larger effect when treated without an endoscopy first.

Compared with placebo [1]; H2 blockers and prokinetic drugs [1]

The numbers and sources

Effect: In people treated for reflux symptoms without an endoscopy first, the risk ratio for heartburn remission against placebo was 0.37 (95% CI 0.32 to 0.44) for proton pump inhibitors and 0.77 (95% CI 0.60 to 0.99) for H2 blockers, a value below 1 favoring the drug. Against H2 blockers directly, proton pump inhibitors had a risk ratio of 0.66 (95% CI 0.60 to 0.73). In people with heartburn and a normal endoscopy, the risk ratio against placebo was 0.71 (95% CI 0.65 to 0.78) [1].
Population: 34 randomized trials of short-term treatment in adults with reflux symptoms, 15 treating without endoscopy, 15 in people with a normal endoscopy and 4 in both [1].
Sources: [1]
Caveats: Short-term trials only. The placebo comparison in people treated without endoscopy rests on two trials [1].

Proton pump inhibitorsModerateVery common

Healing erosive esophagitis

Shown to heal erosive esophagitis more often than placebo or H2 blockers. In one label trial, 92.6% healed on pantoprazole 40 mg by 8 weeks against 39.7% on placebo.

Compared with placebo [2][3]; H2 blockers [2]; nizatidine [3]

The numbers and sources

How common: Very common: more than 1 in 10 people.
Effect: Standard-dose proton pump inhibitors healed esophagitis more often than placebo (RR 0.22, 95% CI 0.15 to 0.31, a value below 1 favoring the drug) and more often than H2 blockers alone or with prokinetics (RR 0.51, 95% CI 0.44 to 0.59). H2 blockers also beat placebo (RR 0.74) [2]. In a US placebo-controlled trial, 8-week healing was 66.0% on pantoprazole 10 mg, 83.5% on 20 mg and 92.6% on 40 mg against 39.7% on placebo. Against nizatidine 150 mg twice daily, 8-week healing was 79.2% and 82.9% on pantoprazole 20 and 40 mg and 41.4% on nizatidine [3].
Population: 134 trials with 35,978 people with esophagitis, of which 5 trials with 965 people compared a standard dose with placebo [2]; 603 adults with grade 2 or higher esophagitis in the placebo trial and 243 in the nizatidine trial [3].
Sources: [2], [3]
Caveats: Cochrane withdrew the 2007 review in 2011 [2]. The label trials were analyzed per protocol, and the placebo group had 68 people [3].

Proton pump inhibitorsModerateVery common

Keeping esophagitis healed

Shown to keep healed esophagitis from returning more often than ranitidine, with 83% to 86% still healed at 12 months on pantoprazole 40 mg against 35% to 37%.

Compared with ranitidine 150 mg twice daily [3]

The numbers and sources

How common: Very common: more than 1 in 10 people.
Effect: In two identical 12-month trials, the share still healed at 12 months was 86% and 83% on pantoprazole 40 mg, 70% and 72% on 20 mg, and 35% and 37% on ranitidine. Daytime heartburn episodes in month 12 averaged 2.9 on pantoprazole 40 mg against 17.5 on ranitidine [3].
Population: 386 and 404 adults with endoscopically healed erosive esophagitis [3].
Sources: [3]
Caveats: The comparison was an H2 blocker, not placebo. Controlled studies did not extend beyond 12 months [3].

Proton pump inhibitorsModerate

Esomeprazole against other proton pump inhibitors

Shown to heal slightly more erosive esophagitis with esomeprazole than with other proton pump inhibitors, about 1 extra healed for every 25 treated, more in severe disease.

Compared with other proton pump inhibitors [4]

The numbers and sources

Effect: At 8 weeks, esomeprazole raised the chance of healing by 5% relative to other proton pump inhibitors (RR 1.05, 95% CI 1.02 to 1.08), an absolute difference of 4% and a number needed to treat of 25. By severity grade A to D, the numbers needed to treat were 50, 33, 14 and 8. Symptom relief at 4 weeks was 8% more likely (RR 1.08, 95% CI 1.05 to 1.11) [4].
Population: 10 randomized trials with 15,316 people with erosive esophagitis [4].
Sources: [4]
Caveats: The abstract does not name the comparator drugs or doses one by one. The trials were published from 1995 to 2005. The gap was small in milder disease [4].

Proton pump inhibitorsModerate

Rebleeding from stomach and duodenal ulcers

Shown to cut rebleeding, surgery and repeat endoscopy after ulcer bleeding, about 1 rebleed prevented per 13 treated, with no overall change in deaths.

Compared with placebo or H2 blockers [5]

The numbers and sources

Effect: Proton pump inhibitors cut rebleeding (OR 0.49, 95% CI 0.37 to 0.65, number needed to treat 13), surgery (OR 0.61, 95% CI 0.48 to 0.78, number needed to treat 34) and repeat endoscopic treatment (OR 0.32, 95% CI 0.20 to 0.51). Deaths did not differ overall (OR 1.01, 95% CI 0.74 to 1.40). Deaths fell in Asian trials (OR 0.35) and in people with active bleeding or a visible vessel (OR 0.53) [5].
Population: 24 randomized trials with 4,373 people with bleeding peptic ulcers [5].
Sources: [5]
Caveats: Heterogeneity was present for rebleeding. The mortality benefit appeared only in subgroups [5].

Proton pump inhibitorsModerateCommon

Preventing ulcers in people taking NSAIDs

Shown to prevent stomach and duodenal ulcers seen on endoscopy in people taking NSAIDs, with gastric ulcers in about 5% on esomeprazole against 12% to 17% on placebo.

Compared with placebo [6][7]

The numbers and sources

How common: Common: between 1 in 100 and 1 in 10 people.
Effect: Proton pump inhibitors lowered the risk of endoscopic gastric ulcers (RR 0.40, 95% CI 0.32 to 0.51) and duodenal ulcers in long-term NSAID users. The review found ulcer complications such as bleeding were shown to fall only with high-dose misoprostol [6]. In two 26-week trials in people aged 60 or older or with a past ulcer, 95.4% and 94.7% stayed free of gastric ulcers on esomeprazole 20 mg against 88.2% and 83.3% on placebo [7].
Population: 40 randomized trials of drugs to prevent NSAID ulcers [6]; 1,429 adults taking NSAIDs, median age 66, in two trials [7].
Sources: [6], [7]
Caveats: Endoscopic ulcers are a stand-in for bleeding ulcers. The esomeprazole trials did not show a drop in duodenal ulcers because there were too few [7].

Proton pump inhibitorsModerate

Stress ulcer bleeding in intensive care

Shown to lower clinically important upper gut bleeding in critically ill adults, 1.0% against 3.5% in one trial, with no difference in deaths at 90 days.

Compared with placebo [10][11]

The numbers and sources

Effect: In ventilated adults, clinically important upper gut bleeding occurred in 1.0% on pantoprazole and 3.5% on placebo (HR 0.30, 95% CI 0.19 to 0.47). Deaths at 90 days were 29.1% and 30.9% (HR 0.94, 95% CI 0.85 to 1.04) [10]. In adults with an unplanned ICU admission, clinically important bleeding occurred in 2.5% on pantoprazole and 4.2% on placebo. Deaths at 90 days were 31.1% and 30.4% (RR 1.02, 95% CI 0.91 to 1.13), and a composite of bleeding, pneumonia, C. difficile infection and heart ischemia did not differ [11].
Population: 4,821 adults on invasive ventilation in 68 ICUs [10]; 3,298 adults at risk of gut bleeding in European ICUs [11].
Sources: [10], [11]
Caveats: Both trials used intravenous pantoprazole in critically ill adults. The results do not apply to people outside intensive care.

Proton pump inhibitorsModerate

Helicobacter pylori ulcers, as part of eradication therapy

Shown, as part of eradication therapy with antibiotics, to heal more duodenal ulcers than ulcer-healing drugs alone, with 12.4% of ulcers persisting against 18.7%.

Compared with ulcer-healing drugs alone or no treatment [12]

The numbers and sources

Effect: In duodenal ulcer healing, eradication therapy plus an ulcer-healing drug left ulcers persisting in 12.4% against 18.7% on the ulcer-healing drug alone (RR 0.66, 95% CI 0.58 to 0.76), and in 21.7% against 58.5% with no treatment (RR 0.37). Differences for gastric ulcer healing were imprecise (RR 1.23, 95% CI 0.90 to 1.68) [12].
Population: 55 randomized trials in people with peptic ulcer and H. pylori infection [12].
Sources: [12]
Caveats: Eradication regimens combine an acid reducer with antibiotics, so this block does not isolate the proton pump inhibitor. The evidence was rated low to very low quality [12].

Proton pump inhibitorsModerate

Functional dyspepsia

Shown to relieve overall indigestion symptoms slightly more than placebo in functional dyspepsia, with about 11 treated for one extra person helped.

Compared with placebo [13]; H2 blockers and prokinetic drugs [13]

The numbers and sources

Effect: Proton pump inhibitors lowered the risk of persisting dyspepsia symptoms against placebo (RR 0.88, 95% CI 0.82 to 0.94), a number needed to treat of 11. Against H2 blockers the difference was not clear (RR 0.88, 95% CI 0.74 to 1.04). Low and standard doses performed similarly [13].
Population: 25 randomized trials with 8,453 participants, 18 trials with 6,172 people for the placebo comparison [13].
Sources: [13]
Caveats: Moderate-quality evidence. Results did not differ by H. pylori status [13].

AmitriptylineLimited

Irritable bowel syndrome

One trial found low-dose amitriptyline improved irritable bowel syndrome symptoms more than placebo over 6 months in primary care.

Compared with placebo [10]

The numbers and sources

Effect: At 6 months, symptom severity scores improved by 27.0 points more on amitriptyline than placebo (95% CI -46.9 to -7.10). 20% stopped amitriptyline, 13% for adverse events, against 26% and 9% on placebo [10].
Population: 463 adults with irritable bowel syndrome still symptomatic after first-line treatments, in 55 English general practices [10].
Sources: [10]
Caveats: One trial. The difference was below the trial's 35-point threshold for a clinically important change [10].

OndansetronLimited

Nausea and vomiting with radiotherapy

Small trials found ondansetron prevented vomiting from radiotherapy better than placebo, metoclopramide and prochlorperazine.

Compared with placebo, metoclopramide and prochlorperazine [3]

The numbers and sources

Effect: Ondansetron 8 mg prevented vomiting from total body irradiation more than placebo, and gave more complete control of vomiting than metoclopramide with single high-dose abdominal radiotherapy and than prochlorperazine with daily fractionated abdominal radiotherapy [3].
Population: 20, 105 and 135 patients in three trials, as reported in the label [3].
Sources: [3]
Caveats: The label gives no rates for these trials, and the placebo-controlled trial had 20 patients [3].

OndansetronLimitedStudied in pregnancy

Nausea and vomiting in pregnancy

One small trial in pregnancy found ondansetron eased nausea more than doxylamine with pyridoxine over 5 days.

Compared with doxylamine with pyridoxine [7]

The numbers and sources

Effect: Median nausea scores fell 51 mm on a 100 mm scale on ondansetron 4 mg against 20 mm on doxylamine with pyridoxine, and vomiting scores fell 41 against 17 mm. Sedation and constipation did not differ [7].
Population: 36 pregnant women with nausea and vomiting, 30 completing follow-up [7].
Sources: [7]
Caveats: A very small trial with uneven follow-up (72% and 94%) and no placebo group [7]. Use in pregnancy is off-label.

Proton pump inhibitorsModerate

Stomach protection with aspirin, clopidogrel or blood thinners

Mixed results: omeprazole cut stomach bleeding events in people on aspirin and clopidogrel, while pantoprazole did not cut overall upper gut events in people on aspirin or rivaroxaban.

Compared with placebo [8][9]

The numbers and sources

Effect: In people on aspirin and clopidogrel, upper gut events over 180 days were 1.1% on omeprazole and 2.9% on placebo (HR 0.34, 95% CI 0.18 to 0.63), and overt upper gut bleeding fell (HR 0.13) [8]. In people with stable heart or artery disease on low-dose rivaroxaban, aspirin or both, upper gut events did not differ (102 of 8,791 on pantoprazole against 116 of 8,807 on placebo, HR 0.88, 95% CI 0.67 to 1.15). Bleeding from stomach and duodenal lesions fell (HR 0.52, 95% CI 0.28 to 0.94), with 982 needing treatment to prevent one [9].
Population: 3,761 patients with coronary disease on dual antiplatelet therapy [8]; 17,598 patients with stable cardiovascular or peripheral artery disease, median 3 years [9].
Sources: [8], [9]
Caveats: The first trial ended early with fewer people than planned [8]. The two trials enrolled different populations at different bleeding risk.

Proton pump inhibitorsModerate

Throat reflux (laryngopharyngeal reflux)

Mixed results: two meta-analyses found throat reflux symptom scores improved more than on placebo, but disagreed on response rates, and throat exam findings did not differ.

Compared with placebo [14][15]

The numbers and sources

Effect: One meta-analysis found a higher response rate on a proton pump inhibitor (risk difference 0.15, 95% CI 0.01 to 0.30) and better reflux symptom index scores (SMD 1.65), with no difference in the reflux finding score seen on laryngoscopy (SMD 0.62, 95% CI -0.96 to 2.19) [14]. A second found better symptom index scores (SMD 3.65, 95% CI 1.56 to 5.75) but no significant difference in response rate or the reflux finding score [15].
Population: 14 randomized trials with 771 participants [14]; 13 randomized trials with 831 participants [15].
Sources: [14], [15]
Caveats: Small trials with differing definitions of response. The two analyses overlap in the trials they include.

Low-dose naltrexoneLimited

Crohn's disease

Small trials found more clinical and endoscopic responses than placebo in Crohn's disease, while remission did not differ significantly. Evidence was rated low quality.

The numbers and sources

Effect: A Cochrane review found 2 RCTs (46 participants). In 34 adults, 4.5 mg a day for 12 weeks led to clinical remission in 30% against 18% on placebo (RR 1.48, 95% CI 0.42 to 5.24). A 70-point clinical response occurred in 83% against 38% (RR 2.22, 95% CI 1.14 to 4.32), and endoscopic response in 72% against 25% (RR 2.89, 95% CI 1.18 to 7.08). Endoscopic remission did not differ significantly [9].
Population: 34 adults with active Crohn's disease and 12 children [9].
Sources: [9]
Caveats: The review rated the evidence as low quality because of sparse data and found it insufficient for firm conclusions [9].

BuspironeModerate

Indigestion and gastroparesis symptoms

Not shown to improve functional dyspepsia or gastroparesis symptoms more than placebo. Bloating alone improved in two small trials.

The numbers and sources

Effect: Across three trials, buspirone did not improve functional dyspepsia or gastroparesis symptoms against placebo (SMD -0.14, 95% CI -0.44 to 0.17). Bloating severity improved (SMD -0.41, 95% CI -0.77 to -0.04, 2 studies) [12]. In a 4-week trial in people with gastroparesis symptoms, early fullness scores did not differ from placebo (difference -0.11, 95% CI -0.68 to 0.45) [13].
Population: 283 people in 10 studies, 5 of them RCTs [12]; 96 patients, 92% women [13].
Sources: [12], [13]
Caveats: Small trials, most lasting 4 weeks. Not an approved use.

Peptides and SARMs

CJC-1295 and ipamorelinGrey marketLimited

Bowel recovery after surgery

One trial found intravenous ipamorelin did not significantly shorten time to the first solid meal after bowel surgery, 25.3 against 32.6 hours.

The numbers and sources

Effect: In a randomized, double-blind, placebo-controlled phase 2 trial of intravenous ipamorelin after bowel resection, median time to the first tolerated solid meal was 25.3 hours on ipamorelin and 32.6 hours on placebo (p = 0.15). No key or secondary efficacy measure differed between the groups [4].
Population: 117 adults having open or laparoscopic small or large bowel resection, 114 of them analyzed, treated twice daily for up to 7 days or until discharge [4].
Sources: [4]
Caveats: A small proof-of-concept trial that enrolled patients with a broad range of underlying conditions, as its authors note [4]. It tested hospital use after surgery, not the uses people take ipamorelin for.

BPC-157Grey marketUntested

Gut healing

Not studied in people. Rat studies report colitis counteracted, and surgical joins in the intestine and fistulas healed.

No study in people. This rests on animal studies.

The numbers and sources

Effect: A 2012 review reports that in animal studies BPC-157 healed intestinal anastomoses, reversed short bowel syndrome and healed fistulas, and describes an antiulcer effect [22]. A 2024 review of rat studies reports that BPC-157 healed surgical joins at several points along the gut, counteracted colitis, esophagitis and short bowel syndrome, and healed fistulas running from the colon, stomach, esophagus or duodenum to the skin [23].
Population: Rats [22][23].
Sources: [22], [23]
Caveats: The 2012 review states that BPC-157 was tested in inflammatory bowel disease in a phase II clinical trial [22]. No published results of that trial were located for this page, so it is not graded here. FDA found no studies giving BPC-157 to humans by mouth [3].

KPVGrey marketUntested

Gut inflammation and colitis

Not studied in people. In mice and rats with induced colitis, KPV reduced colon inflammation and weight loss.

No study in people. This rests on animal studies, lab studies.

The numbers and sources

Effect: In human intestinal and immune cell lines, KPV entered cells through the PepT1 transporter, inhibited NF-kappaB and MAP kinase inflammatory signaling, and reduced pro-inflammatory cytokine secretion. Given in drinking water, it reduced DSS- and TNBS-induced colitis in mice, with lower pro-inflammatory cytokine expression [8]. In two mouse colitis models, KPV-treated mice recovered earlier, regained more body weight and had fewer inflammatory cells in the colon. In mice with a nonfunctional melanocortin-1 receptor, KPV kept all treated animals alive through DSS colitis [9]. KPV delivered by mouth in nanoparticles reduced mucosal damage and TNF-alpha in a mouse model of ulcerative colitis [10]. KPV in a rectal hydrogel reduced weight loss, disease activity scores, colon shortening and inflammatory cytokines in rats with TNBS colitis [11].
Population: Mice and rats with chemically induced or transfer colitis, and human cell lines in the lab [8][9][10][11].
Sources: [8], [9], [10], [11]
Caveats: Colitis induced in rodents does not show what happens in people with inflammatory bowel disease. Two of the studies gave KPV inside a delivery system, nanoparticles or a hydrogel, rather than on its own [10][11]. FDA found no clinical studies or human exposure data for KPV by any route [3].

Supplements

GingerStrong

Nausea in pregnancy

Shown to improve nausea scores in pregnant women over placebo. Vomiting episodes did not differ significantly.

The numbers and sources

Effect: In 12 RCTs (1,278 pregnant women), ginger improved nausea scores against placebo (MD 1.20, 95% CI 0.56 to 1.84, I² 0%). Vomiting episodes did not differ significantly (MD 0.72, 95% CI -0.03 to 1.46) [1]. In 6 placebo-controlled trials (508 women), about 1 g a day for at least 4 days was associated with 5 times the odds of improvement [2].
Population: Pregnant women with nausea and vomiting [1][2].
Sources: [1], [2]
Caveats: Review [1] rated the evidence low quality with variable outcome reporting. Review [2] notes heterogeneity among trials. Review [1] included English-language trials only.

ProbioticsStrong

Side effects and cure rates during H. pylori treatment

Shown to cut side effects during H. pylori treatment about in half with S. boulardii, and to raise cure rates slightly, 1 more per 18 treated.

The numbers and sources

Effect: Added to eradication therapy, Saccharomyces boulardii raised eradication in 15 adult RCTs (RR 1.07, 95% CI 1.03 to 1.10, number needed to treat 18) and cut overall adverse events from 36.0% to 19.7% (RR 0.51, 95% CI 0.39 to 0.66) [1]. With bismuth quadruple therapy, 11 RCTs (2,295 patients) found higher eradication (RR 1.12, 95% CI 1.06 to 1.18) and fewer adverse events (RR 0.46, 95% CI 0.28 to 0.74) [2]. Lactobacillus added to therapy raised eradication in 32 RCTs (RR 1.10, 95% CI 1.05 to 1.14) and lowered adverse events (RR 0.70, 95% CI 0.58 to 0.84) [3]. A review of 14 Lactobacillus RCTs found higher eradication (RR 1.04) and less diarrhea (RR 0.45), with no significant change in other side effects [4].
Population: Adults and children with H. pylori infection [1][3]. Adults [2][4].
Sources: [1], [2], [3], [4]
Caveats: Certainty was low for adverse events in [1]. Eradication gains with Lactobacillus appeared only with triple therapy [3]. The Lactobacillus reviews disagree on side effects other than diarrhea [3][4].

TurmericStrong

Ulcerative colitis

Shown to raise clinical remission about twofold added to standard treatment in adults with ulcerative colitis. Reviews differ on endoscopic remission.

The numbers and sources

Effect: Across 8 RCTs (482 patients), curcumin added to standard treatment raised clinical remission against placebo (RR 2.33, 95% CI 1.25 to 4.34, I² 80%). Endoscopic remission did not differ significantly (RR 4.17, 95% CI 0.63 to 27.71) [22]. A meta-analysis of 6 RCTs (385 participants) found more clinical remission (RR 2.10, 95% CI 1.13 to 3.89) and no significant difference in endoscopic remission [23]. Another of 6 RCTs (349 patients) found more clinical remission (OR 5.18, 95% CI 1.84 to 14.56) and endoscopic remission (OR 5.69, 95% CI 1.28 to 25.27) with curcumin added to mesalamine [24].
Population: Adults with ulcerative colitis, mostly on mesalamine [22][23][24].
Sources: [22], [23], [24]
Caveats: Heterogeneity was high and the trials overlap across the reviews [22]. Some trials gave curcumin as an enema rather than by mouth [24].

Fiber supplementsModerateVery common

Chronic constipation

Shown to help more adults with chronic constipation, 66% against 41% on control, mostly at more than 10 g a day.

The numbers and sources

How common: Very common: more than 1 in 10 people.
Effect: Across 16 RCTs (1,251 adults), 66% responded to fiber and 41% to control (RR 1.48, 95% CI 1.17 to 1.88, I² 57%). Fiber raised stool frequency (SMD 0.72, 95% CI 0.36 to 1.08, I² 86%) and improved stool consistency (SMD 0.32). Psyllium and pectin had significant effects, and response was higher only above 10 g a day [3].
Population: Adults with chronic constipation [3].
Sources: [3]
Caveats: Heterogeneity was considerable. The stool frequency gain appeared only at higher doses and at 4 weeks or more [3].

Fiber supplementsModerate

Irritable bowel syndrome

Shown to lower persistent IBS symptoms in adults, with soluble fiber helping one extra person for every 7 treated. Bran did not differ from control.

The numbers and sources

Effect: Across 14 RCTs (906 patients), fiber lowered the risk of persistent IBS symptoms (RR 0.86, 95% CI 0.80 to 0.94, number needed to treat 10). Soluble fiber showed RR 0.83 (95% CI 0.73 to 0.94, number needed to treat 7), and bran did not differ from control (RR 0.90, 95% CI 0.79 to 1.03) [4].
Population: Adults with IBS [4].
Sources: [4]
Caveats: No significant heterogeneity, but the search ended in December 2013.

GingerModerate

Nausea after surgery

Shown to lower nausea scores in the 12 hours after surgery. Vomiting and anti-nausea drug use did not differ outside the recovery room.

The numbers and sources

Effect: In 14 RCTs (1,506 patients), nausea scores were lower with ginger than placebo at 2, 6 and 12 hours after surgery (SMD -1.10, -1.54 and -2.04). Outside the recovery room, vomiting, combined nausea and vomiting, and use of anti-nausea drugs did not differ [3].
Population: 1,506 surgical patients [3].
Sources: [3]
Caveats: Confidence intervals were wide, for example -3.67 to -0.41 at 12 hours [3].

ProbioticsModerate

C. difficile diarrhea during antibiotics

Shown to halve C. difficile diarrhea during antibiotics, 1.6% against 3.2%, with benefit only where baseline risk was above 5% in one analysis.

The numbers and sources

Effect: In the 2025 Cochrane update, 38 trials (13,179 participants) found C. difficile-associated diarrhea in 1.6% on probiotics and 3.2% on control (RR 0.50, 95% CI 0.38 to 0.64, low certainty, number needed to treat 65) [11]. The 2017 version found 1.5% against 4.0% in 31 trials (RR 0.40) [12]. In its trials with baseline risk above 5%, rates were 3.1% versus 11.6% (RR 0.30), and trials with baseline risk of 5% or less showed no difference [12]. A 2025 review of 4 studies in hospitalized patients found no significant difference (OR 0.99, 95% CI 0.56 to 1.7) [13].
Population: Adults and children on antibiotics, 47 studies with 15,260 participants [11]. Hospitalized patients, 4 studies [13].
Sources: [11], [12], [13]
Caveats: Detection of C. difficile in stool did not differ (RR 0.87, 95% CI 0.68 to 1.11) [11]. 28 studies had authors linked to probiotic companies or company funding [11]. The baseline-risk subgroup in [12] was post hoc. The small hospital review had high heterogeneity [13].

ProbioticsModerate

Antibiotic-associated diarrhea

Shown to lower antibiotic-associated diarrhea, from 19% to 8% in children and 27% to 23% overall, with low to moderate certainty.

The numbers and sources

Effect: Across 33 studies (6,352 children), antibiotic-associated diarrhea occurred in 8% on probiotics and 19% on control (RR 0.45, 95% CI 0.36 to 0.56, I² 57%, number needed to treat 9, moderate certainty). At 5 billion CFU a day or more, rates were 8% versus 23% (RR 0.37) [14]. In 40 trials (13,419 adults and children), antibiotic-associated diarrhea occurred in 23% on probiotics and 27.4% on control (RR 0.67, 95% CI 0.57 to 0.78, low certainty) [11].
Population: Children 0 to 18 on antibiotics [14]. Adults and children on antibiotics [11].
Sources: [14], [11]
Caveats: 20 of 33 pediatric studies were at high risk of bias [14]. Certainty in [11] was downgraded for few events or publication bias.

ProbioticsModerate

Ulcerative colitis

Shown to raise remission in active ulcerative colitis over placebo, with low certainty. Effect on keeping remission was uncertain.

The numbers and sources

Effect: A Cochrane review of 14 studies (865 participants) found more clinical remission in active disease on probiotics than placebo (RR 1.73, 95% CI 1.19 to 2.54, 9 studies, 594 participants, low certainty, number needed to treat 5). Remission did not differ from 5-ASA (RR 0.92, 95% CI 0.73 to 1.16, 1 study) [20]. For keeping remission, a Cochrane review of 12 studies (1,473 participants) found it uncertain whether relapse differed from placebo (RR 0.87, 95% CI 0.63 to 1.18) and little or no difference from 5-ASA (RR 1.01, 95% CI 0.84 to 1.22) [21].
Population: Mostly adults with mild to moderate ulcerative colitis [20][21].
Sources: [20], [21]
Caveats: Risk of bias was high in all but two or three studies in each review, and certainty ranged from moderate to very low [20][21].

ProbioticsModerate

Irritable bowel syndrome

Shown to lower IBS symptom severity scores in adults, with effects differing by strain and no clear change in quality of life.

The numbers and sources

Effect: Across 40 RCTs, probiotics lowered the IBS symptom severity score by 33.42 points (95% CI 10.88 to 55.96) and did not significantly change IBS quality of life (MD 1.79, 95% CI -3.00 to 6.57) [24]. In 12 RCTs (1,303 patients), multistrain products lowered the score by 43.66 points (95% CI 21.44 to 65.89), and IBS-specific quality of life and abdominal pain scores did not change significantly [25]. A strain-level review found benefit for Bifidobacterium longum 35624, Lactobacillus rhamnosus GG, Lactiplantibacillus plantarum 299v, Saccharomyces cerevisiae CNCM I-3856 and Bacillus coagulans Unique IS2, and none for E. coli Nissle 1917, L. gasseri BNR17 or L. casei Shirota [26]. In 53 RCTs (5,545 patients), adverse events were no more common than placebo [27]. In children with IBS, 3 RCTs found less abdominal pain (SMD -0.95, 95% CI -1.63 to -0.27) [28].
Population: Adults with IBS [24][25][26][27]. 604 children in 6 RCTs [28].
Sources: [24], [25], [26], [27], [28]
Caveats: Certainty was low, mainly from inconsistency, and trial sequential analysis found the evidence had not reached the required information size [24]. Heterogeneity was 99% in [25]. Effects differ by strain [26][27].

Vitamin B6ModerateStudied in pregnancy

Nausea and vomiting in pregnancy

Shown to ease nausea in pregnancy slightly, under 1 point on nausea scales. Vomiting did not differ significantly in one trial.

The numbers and sources

Effect: Pooled, pyridoxine alone or with another agent improved nausea scores by 0.78 points on the Rhodes scale (95% CI 0.26 to 1.31) and 0.75 points on the PUQE scale (95% CI 0.28 to 1.22) [1]. In a Thai trial, nausea scores fell more on 30 mg a day than on placebo over 5 days (P = 0.0008). Vomiting episodes did not significantly differ (P = 0.055) [2].
Population: 18 studies [1]; 342 women at 17 weeks' gestation or earlier [2].
Sources: [1], [2], [3]
Caveats: Sources disagree on strength. A 2015 Cochrane review of 41 trials found only limited evidence for vitamin B6 and could not pool most outcomes [3]. The 2023 pooled scores mix pyridoxine alone with combinations [1].

ButyrateLimited

Gut health in people without bowel disease

Small trials of butyrate enemas in healthy volunteers found lower gut pain sensitivity and changes in colon antioxidant markers. No trial of oral butyrate in healthy people was located.

The numbers and sources

Effect: In 11 healthy volunteers, a week of nightly butyrate enemas lowered pain, urge and discomfort during rectal balloon stretching, with pain scores 23.9% lower at 50 mmol/L and 42.1% lower at 100 mmol/L than on saline at low pressure [12]. In 16 healthy volunteers, 2 weeks of daily 100 mM butyrate enemas raised glutathione (p < 0.05) and lowered uric acid (p < 0.01) in colon biopsies against saline. CRP, calprotectin, a gut damage marker and inflammation scores on histology did not differ [13].
Population: 11 healthy adults in a crossover trial [12]. 16 healthy adults in a crossover trial [13].
Sources: [12], [13]
Caveats: Both trials gave butyrate into the rectum, not by mouth as supplements are sold. They were small and short, and measured markers and sensitivity, not symptoms in daily life [12][13].

GingerLimited

Indigestion

One trial found a steamed ginger extract improved gut symptom scores over 12 weeks in adults with functional dyspepsia.

The numbers and sources

Effect: In one 12-week placebo-controlled trial of a steamed ginger extract, 480 mg a day improved total gastrointestinal symptom scores and the abdominal pain, constipation, indigestion and reflux sub-scores against placebo. The abstract reports p-values, not effect sizes [10].
Population: 80 adults with mild to moderate functional dyspepsia [10].
Sources: [10]
Caveats: One trial of one branded extract.

GlucomannanLimitedStudied in men

Constipation

One trial found better constipation scores and more frequent bowel movements on konjac glucomannan in male Taekwondo athletes with functional constipation.

The numbers and sources

Effect: In one 8-week double-blind trial, konjac glucomannan improved constipation symptom scores, constipation quality of life, bowel movement frequency and bowel function scores against placebo (p < 0.05 for all) [8].
Population: Elite male Taekwondo athletes with functional constipation by Rome IV criteria, in China [8].
Sources: [8]
Caveats: One trial. The abstract does not give the number enrolled, the dose or effect sizes [8].

ProbioticsLimited

C. difficile recurrence alongside treatment

One trial found fewer C. difficile recurrences, 1.7% against 13.1%, when S. boulardii was added to vancomycin.

The numbers and sources

Effect: In 120 patients with mild to moderate C. difficile infection treated with vancomycin, 500 mg of Saccharomyces boulardii twice a day for 10 days did not change clinical cure (98.4% against 98.3%) and lowered recurrence (1.7% against 13.1%) compared with placebo [43].
Population: 120 patients with toxin-positive C. difficile infection [43].
Sources: [43]
Caveats: One trial. Adverse events did not differ [43].

LactoferrinModerateStudied in children

Diarrhea in young children

Mixed results: a meta-analysis found fewer children with diarrhea, while a 555-child trial found no change in how often it occurred, only shorter episodes.

The numbers and sources

Effect: A 2025 meta-analysis of 14 trials found fewer children with diarrhea on oral lactoferrin than on placebo (OR 0.56, 95% CI 0.41 to 0.75) [2]. In 555 children aged 12 to 18 months followed for 6 months, diarrhea incidence did not differ (5.4 against 5.2 episodes a year). Episodes were shorter (4.8 against 5.3 days), and moderate or severe dehydration was less common (1.0% against 2.6%) [7].
Population: Children under 18 [2]. Weaned children in Peru [7].
Sources: [2], [7]
Caveats: One meta-analysis. Its abstract does not report heterogeneity or certainty of evidence [2]. The 555-child trial was funded by NIH's NICHD, and its first author is the senior author of the review [7][2].

ProbioticsModerate

Acute infectious diarrhea

Mixed results: low-bias trials found no change in diarrhea risk or duration, while Chinese trials found S. boulardii shortened gastroenteritis in children.

The numbers and sources

Effect: In trials at low risk of bias, probiotics did not change the risk of diarrhea lasting 48 hours or more (RR 1.00, 95% CI 0.91 to 1.09, 2 trials, 1,770 participants) or diarrhea duration (MD 8.64 hours shorter, 95% CI 29.4 hours shorter to 12.1 hours longer, very low certainty) [18]. A 2025 review of 10 Chinese trials (1,125 children) found Saccharomyces boulardii CNCM I-745 shortened acute gastroenteritis (SMD -1.63, 95% CI -2.08 to -1.18) and raised the cure rate (RR 1.47) [19].
Population: 82 studies, 12,127 participants, mostly children [18]. Children in China receiving rehydration therapy [19].
Sources: [18], [19]
Caveats: Publication bias appeared on funnel plots, and heterogeneity was marked across all studies [18]. The reviews disagree. The S. boulardii review found no eligible trials outside Chinese databases [19].

Vitamin DModerate

Inflammatory bowel disease

Mixed results: one review found about 36% fewer relapses in inflammatory bowel disease, mostly Crohn's in remission, while another found no change in relapse or activity.

The numbers and sources

Effect: Across 7 RCTs (458 patients), vitamin D lowered clinical relapse against placebo (RR 0.64, 95% CI 0.46 to 0.89). In Crohn's disease in remission the RR was 0.47 (95% CI 0.27 to 0.82), and ulcerative colitis had only 2 studies (67 patients) [37]. In adults, the Harvey Bradshaw Index for Crohn's disease fell by 1.47 points (95% CI -2.47 to -0.47) and hs-CRP fell by 1.58 mg/L [38]. A meta-analysis of 17 trials (1,127 patients) found lower CRP (SMD -0.33) and no change in disease activity (SMD -0.13, 95% CI -0.66 to 0.39) or relapse (RR 0.59, 95% CI 0.19 to 1.86) [39].
Population: Adults with Crohn's disease or ulcerative colitis [37][38][39].
Sources: [37], [38], [39]
Caveats: The reviews disagree on relapse. Evidence for ulcerative colitis is thin [37].

BoswelliaLimited

Collagenous colitis

One very small trial in collagenous colitis found more remission than placebo per protocol, 63.6% against 26.7%, but not by intention to treat.

The numbers and sources

Effect: In 31 patients with chronic diarrhea from collagenous colitis, 400 mg three times a day for 6 weeks led to remission in 63.6% against 26.7% on placebo per protocol (p 0.04). By intention to treat, it was 43.8% against 26.7% (p 0.25). Histology and quality of life did not differ [5].
Population: 31 randomized, 26 analyzed per protocol [5].
Sources: [5]
Caveats: Very small. The intention-to-treat result was not significant [5].

GingerLimited

Vomiting with chemotherapy

Limited evidence: one review found 60% lower odds of acute vomiting with chemotherapy at 1 g a day or less, and a larger review found no change.

The numbers and sources

Effect: Across 18 articles, ginger at 1 g a day or less for more than 3 days cut the odds of acute vomiting by 60% (OR 0.4, 95% CI 0.17 to 0.81, 3 studies, 301 participants, moderate certainty). Overall and delayed vomiting and nausea severity showed no significant association with ginger [4]. A 2026 meta-analysis of 13 RCTs (1,265 participants) found no significant change in acute vomiting (RR 0.73, 95% CI 0.51 to 1.06) or delayed vomiting (RR 1.17, 95% CI 0.75 to 1.83). In subgroups, the effect was larger in patients under 50 [5].
Population: Adults receiving chemotherapy [4][5].
Sources: [4], [5]
Caveats: The acute vomiting result in [4] rests on 3 studies, and the larger review [5] did not reproduce it. Review [4] was funded by Cancer Council Queensland.

MagnesiumLimited

Constipation

Limited evidence: magnesium oxide improved stool frequency and consistency in about half of small studies in functional constipation.

The numbers and sources

Effect: A 2026 systematic review of 7 studies (690 people, 5 of them RCTs) found better stool frequency than the comparator in 4 studies and better stool consistency in 4. Both studies that used a validated constipation quality-of-life tool found between-group improvement. No serious adverse events were reported [9].
Population: Infants, children and adults with functional constipation. Magnesium oxide was the most common form in adults [9].
Sources: [9]
Caveats: Narrative synthesis because of heterogeneity, certainty not formally graded, small samples and confounded interventions. Findings apply to magnesium oxide [9].

Fish oilStrong

Crohn's disease and ulcerative colitis

Not shown to prevent relapse of Crohn's disease in the two large low-bias trials, or of ulcerative colitis.

The numbers and sources

Effect: A Cochrane review of 6 studies (1,039 patients) found 39% relapsed on omega-3 at 12 months against 47% on placebo (RR 0.77, 95% CI 0.61 to 0.98). In the two large low risk-of-bias trials (738 patients) it was 37% against 42% (RR 0.88, 95% CI 0.74 to 1.05) [14]. In those two trials, 4 g a day for up to 58 weeks did not change relapse at 1 year (31.6% against 35.7%, HR 0.82, and 47.8% against 48.8%, HR 0.90) [15]. In ulcerative colitis, 3 studies (138 patients) found relapse rates similar to placebo (RR 1.02, 95% CI 0.51 to 2.03) [16]. Across 13 RCTs in people with bowel disease, relapse had RR 0.85 (95% CI 0.72 to 1.01), from low-quality evidence [17].
Population: Patients with Crohn's disease in remission [14][15]. People with ulcerative colitis in remission [16]. Adults in trials of 24 weeks or more [17].
Sources: [14], [15], [16], [17]
Caveats: The Cochrane authors rated the pooled Crohn's result very low quality because of heterogeneity and publication bias [14]. The ulcerative colitis review had few patients [16].

ProbioticsStrongStudied in children

Constipation in children

Not shown to increase bowel movements in children with functional constipation compared with placebo or standard treatment.

The numbers and sources

Effect: In a network meta-analysis of 41 RCTs, probiotics did not increase weekly bowel movements compared with placebo or any conventional treatment [5]. A second network meta-analysis of 15 RCTs (1,087 children) found no difference from placebo in weekly bowel movements for any probiotic, prebiotic or synbiotic [6]. An umbrella review found no effect on stool frequency (WMD 0.22, 95% CI -0.30 to 0.74) [7].
Population: Children with functional constipation [5][6]. Children in pooled meta-analyses [7].
Sources: [5], [6], [7]
Caveats: Confidence in the network estimates ranged from very low to moderate [5][6]. Adults were not studied in these reviews.

GlutamineModerate

Gut permeability

Not shown to change gut permeability in adults with various diseases. A subgroup taking more than 30 g a day showed a reduction.

The numbers and sources

Effect: Across 10 RCTs (352 participants, mean age 46.5, mixed health conditions), glutamine did not change intestinal permeability (WMD -0.00, 95% CI -0.04 to 0.03). A subgroup above 30 g a day showed a reduction [3]. In 10 men running 60 minutes at 30°C, 0.25 to 0.9 g per kg of fat-free mass 2 hours before lowered a permeability marker; GI symptoms did not change [4].
Population: Adults with various diseases [3]; recreationally active men in heat [4].
Sources: [3], [4]
Caveats: The meta-analysis abstract gives the subgroup dose as both 30 g and 30 mg a day, and its confidence interval (-0.10 to -0.08) does not contain its estimate (-0.01) [3]. A lab marker change without a symptom change [4].

LactoferrinModerateStudied in children

Bowel inflammation and death in preterm infants

Not shown to change necrotizing enterocolitis or deaths in preterm infants.

The numbers and sources

Effect: Lactoferrin did not change necrotizing enterocolitis stage II or III (RR 1.10, 95% CI 0.86 to 1.41, 7 studies, 4,874 infants) or all-cause mortality (RR 0.90, 95% CI 0.69 to 1.17, 11 studies, moderate certainty). With probiotics, sepsis fell (RR 0.25) and necrotizing enterocolitis fell in one study (RR 0.04, very low certainty) [1].
Population: Preterm infants [1].
Sources: [1]
Caveats: The combination studies were few and of poor methodological quality [1].

ProbioticsModerate

Crohn's disease

Not shown to bring or keep remission in Crohn's disease, in very small studies.

The numbers and sources

Effect: A Cochrane review of 2 studies (46 participants) found no difference from placebo in inducing remission after 6 months (RR 1.06, 95% CI 0.65 to 1.71, very low certainty) [22]. A Cochrane review of 7 small maintenance studies found no significant reduction in relapse with E. coli Nissle (RR 0.43, 95% CI 0.15 to 1.20) or Lactobacillus GG after surgery (RR 1.58, 95% CI 0.30 to 8.40) or medical treatment (RR 0.83, 95% CI 0.25 to 2.80) [23].
Population: Adults and children with Crohn's disease [22][23].
Sources: [22], [23]
Caveats: Studies were very small and could not be pooled for maintenance [23].

BoswelliaLimited

Crohn's disease remission

One trial found boswellia did not keep more people with Crohn's disease in remission than placebo over 52 weeks, 59.9% against 55.3%.

The numbers and sources

Effect: In 82 patients with Crohn's disease in remission, a boswellia extract at 6 × 400 mg a day for up to 52 weeks kept 59.9% in remission against 55.3% on placebo (p 0.85). Time to relapse was 171 days against 185. Disease activity and inflammation markers did not differ [4].
Population: 82 randomized outpatients at 22 German centers, 66 analyzed [4].
Sources: [4]
Caveats: The trial was stopped early because the drug and placebo did not separate [4].

Licorice rootLimited

Stomach ulcers

Small trials found deglycyrrhizinated licorice healed stomach and duodenal ulcers no better than placebo. Added to antibiotics, licorice raised H. pylori clearance in one trial.

Compared with placebo [9][10][11]; cimetidine [12]; clarithromycin-based triple therapy alone [13]

The numbers and sources

Effect: In 96 people with gastric ulcer, healing after 4 weeks did not differ between deglycyrrhizinated licorice and placebo, by gastroscopy, radiology, ulcer area or symptoms [9]. A crossover trial of 760 mg three times a day for 4 weeks in 38 people found no faster healing than placebo [10]. In 47 people with duodenal ulcer, a month of deglycyrrhizinated licorice showed no advantage over placebo [11]. Against cimetidine in 100 people with gastric ulcer, healing did not differ, about 63% at 6 weeks and 91% at 12 weeks [12]. Added to clarithromycin-based triple therapy for 2 weeks, licorice cleared H. pylori in 83.3% against 62.5% on triple therapy alone [13].
Population: 96 [9], 38 [10] and 100 [12] adults with gastric ulcer. 47 adults with duodenal ulcer [11]. 120 adults with H. pylori and dyspepsia, 30% with peptic ulcer [13].
Sources: [9], [10], [11], [12], [13]
Caveats: The ulcer healing trials are small and were published from 1971 to 1982. The cimetidine comparison was single-blind with no placebo group [12]. The H. pylori trial measured clearance of the infection, not ulcer healing, and the abstract does not describe blinding [13].

BromelainUntested

Digestion

Not studied in people. In mice, bromelain raised pancreatic trypsin activity and shifted gut bacteria, and high doses loosened a lab model of human gut lining.

No study in people. This rests on animal studies, lab studies.

The numbers and sources

Effect: Healthy young mice fed 1 mg of bromelain a day for 3 days showed higher pancreatic trypsin activity, a thicker ileal lining, fewer Proteobacteria and more Akkermansia muciniphila in the gut. In a reconstructed human intestinal tissue model, the highest dose disrupted the tissue barrier and raised its permeability [12].
Population: C57BL/6 mice and a human 3D intestinal tissue model [12].
Sources: [12]
Caveats: A 3-day mouse study and a tissue model do not show an effect on digestion in people [12]. No trial of bromelain as a digestive aid in people was located. One 8-week trial in 70 people with ulcerative colitis found lower disease activity scores on 400 mg a day than placebo, with no change in quality of life, which is a different question from everyday digestion [13].

DandelionUntested

Digestion

Not studied in people. The EU herbal committee accepts dandelion root with herb for mild digestive symptoms and temporary loss of appetite on the basis of long-standing use.

No study in people. This rests on documented traditional use.

The numbers and sources

Effect: The European Union herbal monograph lists dandelion root with herb as a traditional herbal medicinal product for the relief of symptoms of mild digestive disorders, such as a feeling of fullness, flatulence and slow digestion, and temporary loss of appetite. It states the indication rests exclusively on long-standing use [6].
Population: A regulator's review of traditional use in the EU [6].
Sources: [6]
Caveats: Traditional use records how a herb has been used, not a measured effect. No trial of dandelion for digestion was located.

Therapies

Hypnotherapy and clinical hypnosisStrong

Irritable bowel syndrome, compared with education, support or routine care

Shown to relieve irritable bowel syndrome more than education, supportive therapy or routine care, with adequate relief in about 33% to 41% against 17% in the largest trial.

Compared with education and/or support, or routine care [3]; control conditions the source abstract does not describe [4]; group educational supportive therapy [5]; online self-guided psychoeducation [6]

The numbers and sources

Effect: A network meta-analysis of 41 trials found gut-directed hypnotherapy reduced the chance of remaining symptomatic (RR 0.67, 95% CI 0.49 to 0.91), and in refractory IBS it beat education, support or routine care [3]. Across 8 trials, hypnosis gave adequate symptom relief more often than control at the end of therapy (RR 1.69, 95% CI 1.14 to 2.51, number needed to treat 5) and at long-term follow-up (RR 2.17, number needed to treat 3) [4]. In 354 adults referred from primary or secondary care, adequate relief at 3 months was 40.8% with individual hypnotherapy, 33.2% with group hypnotherapy and 16.7% with educational supportive therapy (OR 2.9, 95% CI 1.2 to 7.4), and 40.8%, 49.5% and 22.6% at 12 months [5]. In 230 people, an abdominal pain response was seen in 48% with in-person hypnotherapy, 33% with a smartphone program and 22% with psychoeducation [6]. The American College of Gastroenterology guideline states: "We suggest that gut-directed psychotherapy be used to treat global IBS symptoms" [7], a conditional recommendation based on very low-quality evidence according to NCCIH [2].
Population: 4,072 adults in 41 trials of psychological therapies [3]. 464 adults in 8 trials, mostly with IBS that had not responded to usual treatment [4]. 354 adults in 11 Dutch hospitals [5]. 230 people aged 16 to 75 [6].
Sources: [3], [4], [5], [6], [7], [2]
Caveats: Trials were at high risk of bias, with funnel plot asymmetry suggesting effects are overestimated [3]. A 2007 Cochrane review of 4 small early trials judged their quality too poor for conclusions [8]. No trial can blind patients to receiving hypnotherapy.

AcupunctureModerate

Nausea and vomiting after surgery

Shown to cut nausea after surgery by about a third compared with sham, with stimulation of one wrist point. It did not differ from antinausea drugs.

Compared with sham treatment [11]; antinausea drugs [11]

The numbers and sources

Effect: Stimulating the PC6 wrist point lowered nausea (RR 0.68, 95% CI 0.60 to 0.77, 40 trials, 4,742 participants), vomiting (RR 0.60, 95% CI 0.51 to 0.71) and the need for rescue drugs (RR 0.64) against sham. It did not differ from six antinausea drugs, including ondansetron and dexamethasone, for nausea (RR 0.91, 95% CI 0.75 to 1.10) or vomiting (RR 0.93). Added to a drug, it lowered vomiting (RR 0.56) and not nausea [11].
Population: 59 trials with 7,667 surgical patients [11].
Sources: [11]
Caveats: The review pooled needles, electrical stimulation, acupressure and wristbands. Heterogeneity was substantial and the sham evidence was rated low in quality [11].

Biofeedback and neurofeedbackModerate

Constipation from pelvic floor dyssynergia, compared with laxatives and other treatment

Shown to improve constipation from pelvic floor dyssynergia more often than laxatives, diazepam or other non-biofeedback treatment, in trials rated low in quality.

Compared with laxatives with diet and lifestyle advice, oral diazepam, and standard care [11]; non-biofeedback therapy [12]

The numbers and sources

Effect: Against non-biofeedback therapy, biofeedback raised the odds of clinical improvement (OR 3.63, 95% CI 1.10 to 11.93, 6 trials), and 63% of treated patients improved [12]. In one trial, 80% given biofeedback improved at 6 and 12 months against 22% given laxatives (RR 3.65). In another, 70% improved against 23% on diazepam (RR 3.00). Some surgical procedures did better than biofeedback [11].
Population: 725 adults in 11 trials [12]. 931 adults in 17 trials, most with dyssynergic defecation [11].
Sources: [12], [11]
Caveats: Sixteen of 17 trials were at high risk of bias for blinding, and heterogeneity was high [11][12].

AcupunctureLimited

Chronic constipation, electroacupuncture

One trial of 1,075 people found electroacupuncture added about one complete bowel movement a week more than sham, through 12 weeks after treatment.

Compared with sham electroacupuncture at non-acupoints [20]

The numbers and sources

Effect: Weekly complete spontaneous bowel movements rose by 1.76 with electroacupuncture and 0.87 with sham over weeks 1 to 8 (difference 0.90, 95% CI 0.74 to 1.10), and by 1.96 and 0.89 over weeks 9 to 20. Three or more a week were reached by 31.3% and 12.1% during treatment [20].
Population: 1,075 people with chronic severe functional constipation at 15 hospitals in China [20].
Sources: [20]
Caveats: Acupuncturists could not be blinded and longer-term follow-up was not assessed [20].
Why limited: This rests on one trial, of 1,075 people. Strength counts independent studies that agree, so one trial is limited at any size.

Biofeedback and neurofeedbackLimited

Constipation from pelvic floor dyssynergia, compared with sham biofeedback

One trial found 4.6 complete bowel movements a week with biofeedback against 2.8 with sham biofeedback at 3 months.

Compared with sham biofeedback [11]

The numbers and sources

Effect: At 3 months, complete spontaneous bowel movements averaged 4.6 a week with manometry biofeedback and 2.8 with sham biofeedback (mean difference 1.80, 95% CI 1.25 to 2.35) [11].
Population: 52 adults with chronic constipation and dyssynergic defecation in one trial [11].
Sources: [11]
Caveats: One small trial, and the Cochrane review rated the evidence low or very low [11].

Colon hydrotherapyLimited

Irritable bowel syndrome

One pilot study of 18 people with irritable bowel syndrome found less abdominal pain and more regular stools after 1 to 4 weeks, with no control group.

Compared with before treatment, in the same people [5]

The numbers and sources

Effect: Abdominal pain, satisfaction and distress scores improved (p < 0.001). In constipation-dominant IBS, bowel movements rose from 1.68 to 3.78 a week and hard stools fell from 45% to 13%. In diarrhea-dominant IBS, loose stools fell from 62% to 28%. Only mild adverse events occurred [5].
Population: 18 patients with IBS, 12 constipation-dominant and 6 diarrhea-dominant, using a self-administered irrigation device [5].
Sources: [5]
Caveats: No control group, so placebo and natural change cannot be separated. The authors call for studies of placebo effects [5].

Hypnotherapy and clinical hypnosisModerateStudied in children

Stomach pain and irritable bowel syndrome in children

Mixed results: pooled trials found more children treated successfully than with no intervention, while a primary care trial found no difference in relief at 12 months.

Compared with no intervention [9]; care as usual [10]

The numbers and sources

Effect: Hypnotherapy led to treatment success more often than no intervention (RR 2.86, 95% CI 1.19 to 6.83, number needed to treat 5), at low certainty [9]. In 152 children aged 7 to 17 treated in primary care, home-based guided hypnotherapy added to usual care did not change adequate relief at 12 months (79.5% against 74.3%, adjusted OR 1.47). More children had relief at 3 months (adjusted OR 2.74) and 6 months (4.26) [10].
Population: 91 children in 2 trials of hypnotherapy against no intervention [9]. 152 children in Dutch primary care [10].
Sources: [9], [10]
Caveats: The pooled result rests on two small trials at risk of bias [9]. Relief was high in both groups by 12 months [10].

Osteopathy and osteopathic manipulative treatmentModerate

Headache, irritable bowel syndrome and other conditions

Mixed results: an overview of 27 reviews found possible relief in migraine and irritable bowel syndrome, and no relief in acute low back pain, fibromyalgia or other headaches.

Compared with no treatment, sham treatment or other non-osteopathic treatment [16]

The numbers and sources

Effect: Osteopathic treatment may relieve symptoms in adults with migraine and irritable bowel syndrome. It did not appear to relieve acute nonspecific low back pain, fibromyalgia, headaches of various causes, lower urinary tract symptoms in women, or cerebral palsy in children. Evidence for vertigo, COPD, high blood pressure and gynecological complaints was insufficient [16]. An earlier overview rated the evidence for children's conditions, headache and irritable bowel syndrome limited and inconclusive [17].
Population: 27 systematic reviews covering nine indications [16]. 9 reviews with 55 trials and 3,740 participants [17].
Sources: [16], [17]
Caveats: Included reviews were rated low or critically low in quality [17], and the trials were heterogeneous and partly of poor quality [16].

Biofeedback and neurofeedbackLimited

Fecal incontinence

Limited evidence: single small trials found biofeedback added to exercises or electrical stimulation improved continence, and the Cochrane review could not draw firm conclusions.

Compared with sphincter exercises alone [14]; electrical stimulation alone [14]; sham training [14]; sacral nerve stimulation [14]

The numbers and sources

Effect: Biofeedback plus exercises beat exercises alone (RR for not reaching full continence 0.70, 95% CI 0.52 to 0.94, one trial), and adding biofeedback to electrical stimulation beat stimulation alone (RR 0.47, one trial). Rectal volume discrimination training improved continence more than sham training in some data. Sacral nerve stimulation gave fewer incontinence episodes than conservative care including biofeedback [14].
Population: 1,525 adults in 21 trials [14].
Sources: [14]
Caveats: Few trials for each comparison and methodological weaknesses [14].

Hypnotherapy and clinical hypnosisModerate

Irritable bowel syndrome, compared with other psychological therapies

Not shown to differ from cognitive behavioral therapy or other psychological therapies for irritable bowel syndrome in a network meta-analysis of 41 trials.

Compared with cognitive behavioral therapy in several formats, and other psychological therapies [3]

The numbers and sources

Effect: Self-guided or minimal-contact CBT (RR 0.61), face-to-face CBT (RR 0.62) and gut-directed hypnotherapy (RR 0.67) all reduced the chance of remaining symptomatic, and none was superior to another. CBT-based therapies and gut-directed hypnotherapy had the largest evidence base and the largest long-term effects [3].
Population: 4,072 adults in 41 trials [3].
Sources: [3]
Caveats: Few trials compared therapies head to head, so most comparisons are indirect [3].

Colon hydrotherapyUntested

General health and detox from colon cleansing

Not studied in people in rigorous controlled trials. The detox idea rests on the old theory of autointoxication, that bowel waste poisons the body.

No study in people. This rests on how it acts in the body, documented traditional use.

The numbers and sources

Effect: A systematic review of conventional and alternative medicine literature found no methodologically rigorous controlled trials of colonic cleansing for general health promotion, and multiple case reports and case series of adverse effects [6]. A history of the practice traces it to autointoxication, the 19th century doctrine that intestinal waste products poison the body, which declined once its scientific rationale was shown to be wrong [7].
Population: No trial population. A systematic review [6] and a historical review [7].
Sources: [6], [7]
Caveats: No study located measured toxins removed from the body by colon cleansing.

Food and drink

Fermented foodsModerate

Bowel habits and gut symptoms in healthy adults

Shown to increase bowel movement frequency and ease gut symptoms in healthy adults, in one meta-analysis of 19 trials rated mostly low in certainty.

Compared with control groups the abstract does not describe [2]

The numbers and sources

Effect: Fermented foods raised bowel movement frequency (MD 0.60, 95% CI 0.04 to 1.16), softened stool on the Bristol scale (MD 0.25, 95% CI 0.03 to 0.47), eased gastrointestinal symptoms (SMD -0.60, 95% CI -1.05 to -0.15) and shortened intestinal transit time (MD -13.65, 95% CI -21.88 to -5.43) [2].
Population: 4,328 healthy adults in 25 studies, 19 randomized trials pooled [2].
Sources: [2]
Caveats: Heterogeneity was high (I² 72% to 95%) and the certainty of evidence was rated mostly low [2]. The trials used different foods.

Fermented foodsModerate

Irritable bowel syndrome

Shown to raise the share of people with irritable bowel syndrome reporting symptom relief by 22%, in one meta-analysis. Pain and bloating scores did not change significantly.

Compared with control groups the abstract does not describe [3]

The numbers and sources

Effect: Symptom relief was more frequent with fermented foods (RR 1.22, 95% CI 1.04 to 1.42, I² 0%, 12 trials), and global symptom scores fell slightly (SMD -0.15, 95% CI -0.29 to -0.02). Abdominal pain and bloating scores did not improve significantly. Fermented milk alone showed RR 1.19 (95% CI 1.01 to 1.39) [3].
Population: 1,264 people with irritable bowel syndrome in 16 randomized trials [3].
Sources: [3]
Caveats: The authors advise caution given limits of the evidence [3]. Many products were fermented milks with added probiotic strains.

Whole grainsModerate

Bowel habits

Shown to raise stool weight by 3.7 g per extra gram of wheat fiber a day, and to shorten slow gut transit, in pooled intervention studies.

Compared with lower intakes of wheat fiber, in a regression across intervention studies [14]

The numbers and sources

Effect: Each extra gram a day of wheat fiber raised total stool weight by 3.7 g a day (95% CI 3.50 to 3.84) and stool frequency by 0.004 times a day. In people whose transit time was over 48 hours, it shortened by 0.78 hours per extra gram (95% CI 0.53 to 1.04). Too few studies of non-wheat cereal fibers allowed analysis [14].
Population: 65 intervention studies in generally healthy people [14].
Sources: [14]
Caveats: Most of the effect came from wheat bran [14]. Fiber in general is on its own page.

Fermented foodsLimited

Gut microbiome diversity

One 17-week trial of 36 adults found a high fermented food diet steadily raised gut microbiome diversity, which a high-fiber diet did not.

Compared with a high-fiber diet, with changes measured over time in each group [8]

The numbers and sources

Effect: The high fermented food diet steadily increased microbiota diversity. The high-fiber diet left community diversity stable. The primary outcome, a cytokine response score, did not change [8].
Population: 36 healthy adults, 18 in each group [8].
Sources: [8]
Caveats: One small trial. Microbiome diversity is not itself a health outcome.

Diets

Carnivore dietLimited

Inflammatory bowel disease

Case reports: 10 people with ulcerative colitis or Crohn's disease, selected because they responded, reported improvement on mostly carnivore ketogenic diets.

Compared with no comparison group [4]

The numbers and sources

Effect: Six people with ulcerative colitis and four with Crohn's disease reported improvement of 72 to 165 points on the Inflammatory Bowel Disease Questionnaire [4].
Population: 10 adults with confirmed inflammatory bowel disease, recruited through a social media survey [4].
Sources: [4]
Caveats: A case series that included only people whose disease responded to the diet, so it cannot show how often it helps. No comparison group [4].

Blood type dietUntested

Digestion

Not studied in people. The diet's idea that food lectins clash with blood types rests on lab work, which found lectins common in foods but no blood-type-specific clumping.

No study in people. This rests on lab studies, how it acts in the body.

The numbers and sources

Effect: A systematic review found no study of any health effect of blood-type diets, digestion included [1]. The diet proposes that lectins, sugar-binding proteins in some foods, cause clumping when they do not suit a person's ABO blood type [2]. In a lab survey, 29 of 88 common foods, including salad ingredients, fresh fruits, roasted nuts and processed cereals, showed lectin activity in agglutination tests [5]. The authors of a 2014 study, citing that survey, wrote that studies to date suggest no ABO-specific agglutination [2].
Population: Food extracts tested in the lab [5]. A systematic review [1] and the background of a study in 1,455 adults [2].
Sources: [1], [2], [5]
Caveats: Lectin activity in a test tube does not show what happens in the gut. No study measured digestive symptoms on a blood-type diet [1].

Lab markers

TriglyceridesLimited

Acute pancreatitis

One cohort of 116,550 Danish adults linked non-fasting triglycerides of 177 mg/dL and above to more acute pancreatitis, about 9 times more at 443 mg/dL or above.

The numbers and sources

Effect: Against triglycerides below 89 mg/dL, multivariable adjusted hazard ratios for acute pancreatitis were 1.6 (95% CI 1.0 to 2.6) at 89 to 176 mg/dL, 2.3 (1.3 to 4.0) at 177 to 265 mg/dL and 8.7 (3.7 to 20.0) at 443 mg/dL or above, where the rate was 12 events per 10,000 person-years. The hazard ratio was 1.17 (95% CI 1.10 to 1.24) per 89 mg/dL higher triglycerides [21]. Guideline bodies place the level of clinically significant pancreatitis risk higher, at 500 mg/dL in a US panel and above 880 mg/dL in European documents [2][5][6].
Population: 116,550 people from two Copenhagen general population studies, median follow-up 6.7 years, 434 cases of acute pancreatitis [21].
Sources: [21], [2], [5], [6]
Caveats: Observational, with few events in the highest band, so its interval is wide. Results were similar after stratifying by alcohol intake and gallstone disease [21].