Gut health
Check what applies to you and the best-matched supplements move to the top.
Nothing checked yetDefault order, by strength of evidence.
Bottom line
For gut health, start with Probiotics, Fiber, Digestive enzymes. The first one to look at is Probiotics — 1 capsule of 5–10 billion CFU a day, with a strain that matches your symptoms (HN019 for constipation, S. boulardii for diarrhea); Before breakfast (after a meal is fine if it upsets your stomach).
Supplements ranked for this concern
AWell researchedBSome evidenceCLimited evidence
| # | Supplement | Evidence | When | How much | Caution | |
|---|---|---|---|---|---|---|
| 1 | ProbioticsMatches your checks Change your gut environment. They may help most with diarrhea and IBS, and play a supporting role for constipation. |
A | Before breakfast (after a meal is fine if it upsets your stomach) | 1 capsule of 5–10 billion CFU a day, with a strain that matches your symptoms (HN019 for constipation, S. boulardii for diarrhea) | If gas or stomach pain lasts more than 2–4 weeks, or you get hives, switch to a different strain. | Compare products |
| 2 | FiberMatches your checks Soaks up water and swells in the gut to help push stool along. It's the most basic ingredient for managing constipation and gas. |
A | On an empty stomach or between meals, with 1–2 glasses of water | About 5 g per serving, 1–2 times a day (start with half a scoop) | If you don't drink enough water, it can actually cause constipation or stomach pain. For IBS, choose a low-FODMAP fiber. | Compare products |
| 3 | Digestive enzymesMatches your checks Break food down into smaller pieces, which may help ease bloating and frequent indigestion. |
B | Just before to right after a meal. Don't take on an empty stomach. | 1–2 capsules per meal, up to 2–3 times a day | With stomach ulcers or severe gastritis they can cause heartburn, so start with a mild product. | Compare products |
| 4 | PrebioticsMatches your checks Feed good bacteria and increase their variety. Good to add for constipation that probiotics alone don't fix. |
B | After meals, with water | 2–8 g a day (start with 1–2 small scoops) | They're a type of sugar, so taking a lot can lead to weight gain. | Details |
| 5 | GlutamineMatches your checks An energy source for gut lining cells that helps the lining recover. Added for gut trouble with diarrhea. |
B | On an empty stomach, split between morning and evening, for 3–6 months | 2–5 g a day | Too much can cause headaches, restlessness or trouble sleeping. If you're being treated for cancer, talk to your doctor. | Details |
| 6 | MagnesiumMatches your checks A gentle constipation aid that draws water into the bowel to soften stool. Also used to ease gut cramps. |
B | After meals (if you take 2+ capsules, split them up) | 200–400 mg a day (magnesium oxide for constipation) | If you get diarrhea, lower the dose or switch to a chelated form. If you have kidney disease, talk to your doctor. | Compare products |
| 7 | Peppermint oilMatches your checks Relaxes gut muscles, which may help ease cramping stomach pain and gurgling. |
B | As directed on the label | The labeled dose of an enteric-coated capsule | It only makes sense as an enteric-coated product that dissolves in the intestine. | Details |
| 8 | ColostrumMatches your checks Its immunoglobulins and growth factors may help strengthen the gut lining. Paired with probiotics for frequent diarrhea and stomach bugs. |
C | 1–2 times a day, with probiotics | 1–2 capsules a day with about 200 mg of immunoglobulins | Some argue it gets digested and doesn't work as is, so judge by how you feel. | Details |
Medications to watch out for
If you take any medication, talk to your doctor or pharmacist before starting.
ImmunosuppressantsProbioticsWith a weakened immune system, bacteria may pass into the blood. Talk to your doctor first.
AntibioticsProbioticsBacterial probiotics work less well. Space them at least 2 hours apart. S. boulardii (a yeast) is less affected.
Blood thinners such as warfarin (Coumadin) and anti-clotting drugsDigestive enzymesSome enzymes are absorbed and may raise bleeding risk. Talk to your doctor.
Iron supplements and multivitaminsFiberTaking a lot of fiber over time can bind minerals and lower their absorption. Take them at different times.
Undergoing cancer treatmentGlutamineIt's a nutrient cells use to grow, so it's best to avoid high doses. Talk to your doctor.
Being treated for kidney diseaseMagnesiumYour body may not clear it well, so it can build up. Talk to your doctor before taking it.
Before supplements: daily habits
- 01Overeating, eating fast, and drinking water or cold drinks with meals can weaken digestion.
- 02Once you find a probiotic that works for you, stick with it instead of switching.
- 03When you add more fiber, drink more water too, or constipation can get worse.
- 04If your stomach is sensitive, just cutting back on habitual coffee can make a big difference.
- 05If diarrhea or constipation drags on, or you have blood in your stool or weight loss, see a doctor first.
Product comparison
| Product | Form | Per serving | Count | Cost per day | |
|---|---|---|---|---|---|
| Saccharomyces Boulardii + MOSBest value Jarrow Formulas |
Saccharomyces boulardii (probiotic yeast) + MOS | 1 capsule: 5 billion | 180 | Low | Amazon → |
| Probiotic-10 25 Billion NOW Foods |
Danisco 10-strain capsule | 1 capsule: 25 billion CFU | 100 | Low | Amazon → |
| Colon Health Daily Probiotic Phillips' |
LGG + BB-12 | 1 capsule: 3 billion CFU (through expiration) | 60 | Low | Amazon → |
| Pro Strength Digestive Daily Probiotic 12 Billion Culturelle |
LGG single strain + inulin | 1 capsule: 12 billion CFU | 60 | Average | Amazon → |
| Ultimate Flora Women's Care 25 Billion Renew Life |
12 strains including vaginal strains (GR-1, RC-14) | 1 capsule: 25 billion CFU | 30 | Average | Amazon → |
| Digestive Daily Probiotic 10 Billion Culturelle |
LGG single strain + inulin | 1 capsule: 10 billion CFU | 30 | Average | Amazon → |
| Probiotic 40 Billion CFU BioSchwartz |
Danisco 4-strain capsule | 2 capsules: 40 billion CFU (20 billion guaranteed through expiration) | 120 | Average | Amazon → |
| Ultimate Flora Extra Care 30 Billion Renew Life |
12-strain capsule, mostly Bifidobacteria | 1 capsule: 30 billion CFU | 30 | Average | Amazon → |
Compare all Probiotics products →
| Product | Form | Per serving | Count | Cost per day | |
|---|---|---|---|---|---|
| Whole Psyllium Husks, 16 ozBest value NOW Foods |
Whole psyllium husk (unflavored, psyllium only) | 2 tablespoons (10 g): fiber 7 g | 45 | Low | Amazon → |
| OPTIFIBER (Wheat Dextrin), 25.6 oz x 2 Kirkland Signature |
Wheat dextrin powder (unflavored, single ingredient) | 2 teaspoons (4 g): fiber 3 g | 380 | Low | Amazon → |
| Psyllium Husk Powder, 12 oz NOW Foods |
Psyllium powder (unflavored, psyllium only) | 1 tablespoon (9 g): fiber 7 g | 37 | Low | Amazon → |
| Prebiotic Fiber Powder, Unflavored, 28 Stick Packs Benefiber |
Wheat dextrin powder sticks (unflavored, single ingredient) | 1 stick (4 g): fiber 3 g | 28 | Average | Amazon → |
| Product | Form | Per serving | Count | Cost per day | |
|---|---|---|---|---|---|
| Plant EnzymesBest value NOW Foods |
Plant- and microbe-derived enzyme blend capsule, basic | 1 capsule: protein 15,000 HUT, carbs 2,500 DU, fat 750 FIP, lactose 200 ALU | 240 | Low | Amazon → |
| Super Enzymes (Capsules) NOW Foods |
Pancreatin (pancreatic enzymes) + betaine HCl + ox bile + papain and bromelain capsule | 1 capsule: pancreatin 134 mg (protein 37,000, carbs 37,000, fat 2,960 USP), betaine HCl 200 mg, ox bile 100 mg | 90 | Low | Amazon → |
| Digest Basic, Essential Digestive Enzyme Formula Enzymedica |
Plant- and microbe-derived enzyme blend capsule (Thera-blend), basic | 1 capsule: protein 20,000 HUT, fat 450 FCCFIP, lactose 300 ALU + carb enzymes | 90 | Average | Amazon → |
| Flatter Me Digestive Enzymes HUM Nutrition |
18 plant-based enzymes capsule (+ small amount of herbs) | 1 capsule: protein 57,500 HUT (3 combined), carbs 3,500 DU, fat 350 FIP, lactose 150 ALU, beans 75 GalU | 60 | High | Amazon → |
| Digest (Digest Complete), Complete Digestive Enzyme Formula Enzymedica |
Plant- and microbe-derived enzyme blend capsule (Thera-blend), medium | 1 capsule: protein 42,000 HUT, carbs 12,000 DU, fat 1,500 FCCFIP, lactose 500 ALU | 90 | High | Amazon → |
| Omega-Zyme Ultra Digestive Enzyme Blend Garden of Life |
Plant-based enzyme blend capsule, strong (+ small amounts of herbs and minerals) | 1 capsule: protein 82,000 HUT, carbs 25,000 DU, fat 5,000 FIP | 90 | High | Amazon → |
| Digest Gold with ATPro, Maximum Strength Enzymedica |
Plant- and microbe-derived enzyme blend capsule (Thera-blend), strong | 1 capsule: protein 80,000 HUT, carbs 23,000 DU, fat 4,000 FIP, lactose 900 ALU | 45 | High | Amazon → |
| Digestive Enzymes Ultra Pure Encapsulations |
Plant-based enzyme blend capsule, strong (per 2 capsules) | 2 capsules: protein 80,000 HUT, carbs 24,000 DU, fat 3,000 FIP, lactose 1,600 ALU | 90 | High | Amazon → |
Compare all Digestive enzymes products →
| Product | Form | Per serving | Count | Cost per day | |
|---|---|---|---|---|---|
| Magnesium Citrate 200 mg TabletsBest value NOW Foods |
Citrate | 400 mg | 250 | Low | Amazon → |
| Magnesium Bisglycinate Powder (Albion)Best value NOW Foods |
Bisglycinate powder (Albion) | 250 mg | 91 | Low | Amazon → |
| Magnesium Citrate Pure PowderBest value NOW Foods |
Citrate powder | 435 mg | 76 | Low | Amazon → |
| Natural CALM Magnesium Powder (Raspberry Lemon)Best value Natural Vitality |
Citrate (magnesium carbonate + citric acid, forms when mixed with water) | 325 mg | 100 | Low | Amazon → |
| Magnesium (Citrate) 100 mg Life Extension |
Citrate | 200 mg | 100 | Low | Amazon → |
| High Absorption Magnesium (Glycinate Lysinate Chelate) Doctor's Best |
Glycinate/lysinate chelate (Albion) | 200 mg | 240 | Low | Amazon → |
| Magnesium Citrate Veg Capsules NOW Foods |
Citrate | 400 mg | 240 | Low | Amazon → |
| Magnesium Glycinate 100 mg (Albion) NOW Foods |
Bisglycinate chelate (Albion) | 200 mg | 180 | Average | Amazon → |
Compare all Magnesium products →
Cost per day is relative — compared with other products of the same supplement. Check Amazon for the current price. Some links are affiliate links.