Ranked by evidence
Best supplements for gut health and digestion
"Gut health" is not one problem, so this page is organised by what each supplement actually treats: constipation, IBS, gas, nausea, diarrhoea during antibiotics. Items are ranked by how strong the evidence is in our own grading, not by how popular they are. Anything sold hard for the gut but backed by thin evidence is in the skip list at the bottom, with the reason.
Evidence last reviewed: August 2026
Top picks
| Option | Evidence | Best for | The honest note | |
|---|---|---|---|---|
| Psyllium Husk (fiber) | Strong evidence | constipation and regularity | Gel-forming soluble fiber with decades of consistent trials for constipation; also lowers LDL cholesterol and helps blood sugar and satiety. | View |
| Peppermint Oil (Enteric-Coated) | Strong evidence | IBS symptoms and abdominal pain | Meta-analytic support for IBS: beats placebo for global symptoms and abdominal pain, number needed to treat around 4. Main trade-off is heartburn. | View |
| Saccharomyces Boulardii | Moderate evidence | diarrhoea while on antibiotics | Probiotic yeast with good evidence for preventing antibiotic-associated diarrhoea; being a yeast, it survives the antibiotic itself. | View |
Solid options
| Option | Evidence | Best for | The honest note | |
|---|---|---|---|---|
| Bifidobacterium Infantis | Moderate evidence | IBS when you want one strain | Strain 35624 improved global IBS symptoms in a well-designed dose-finding trial. Real but modest, and specific to that strain rather than the species. | View |
| Lactobacillus Plantarum | Moderate evidence | bloating and pain in IBS | Strain 299v has moderate evidence for less IBS bloating and abdominal pain. Effects are modest and tied to that strain, not to the species in general. | View |
| Magnesium Citrate | Moderate evidence | occasional constipation | Works reliably as an osmotic laxative and is better absorbed than magnesium oxide — the laxative effect is either the point or the side effect. | View |
Situational
| Option | Evidence | Best for | The honest note | |
|---|---|---|---|---|
| Lactase | Moderate evidence | eating dairy with lactose intolerance | Situational: for lactose maldigestion. Breath-hydrogen studies confirm it works, but results depend on the preparation, dose and timing with the meal. | View |
| Alpha-Galactosidase | Moderate evidence | gas from beans and vegetables | Situational: taken with beans and cruciferous vegetables it cuts gas dose-dependently in small trials. No broad benefit for general bloating or IBS. | View |
| Ginger | Moderate evidence | nausea, especially in pregnancy | Situational: solid for nausea — pregnancy and post-operative especially, motion sickness less so. The joint-pain and anti-inflammatory claims are weak. | View |
| Artichoke Extract | Moderate evidence | indigestion after meals | Situational: decent trial support for functional dyspepsia — upper-gut discomfort after meals. The popular IBS claim rests on much weaker evidence. | View |
Popular for this goal — but the evidence says skip
- L-Glutamine Limited evidence
Genuinely useful in severe catabolic illness, but the intestinal permeability and "leaky gut" claims in healthy people remain evidence-limited.
- Digestive Enzymes Limited evidence
Prescription pancreatic enzymes and lactase work for diagnosed problems; over-the-counter multi-enzyme blends for bloating in healthy people do not.
- Betaine HCl Limited evidence
It really does re-acidify the stomach, but relief of bloating, reflux or "poor digestion" in healthy adults is evidence-limited.
- Activated Charcoal Limited evidence
A real emergency-medicine tool for poisoning, but limited evidence for gas and bloating — and it interferes with medications and nutrients.
- Bone Broth Protein Limited evidence
Spray-dried hydrolyzed collagen with broth flavoring, sold on gut-healing claims that have never been tested in a human trial.
- Colon Cleanse Formulas Limited evidence
A systematic review of colon cleansing for general health found no credible benefit and a documented list of harms.
Our verdict
If you take only one thing, psyllium is the best-proven gut supplement there is, and enteric-coated peppermint oil is the clearest win for IBS. Saccharomyces boulardii is the one worth having on hand before you start a course of antibiotics.