Gut Health
Gut health products — probiotics, digestive enzymes, collagen peptides — sit in one of the youngest fields in this catalog. Probiotic effects in particular are strain-specific: a strain shown to help one condition in one trial doesn't automatically transfer its evidence to a different strain, dose, or use case. Individual variation in baseline gut microbiome composition also makes broad claims harder to support than the marketing usually implies.
6 products · sorted by evidence grade
Common questions
Which gut health supplement has the best evidence?
Psyllium husk is the only Grade A product in this category. A 2025 dose-response meta-analysis of 41 RCTs supports it for lowering LDL cholesterol, and a separate 2022 meta-analysis of 16 RCTs (1,251 adults) supports it for relieving chronic constipation — both uses are graded A, and it carries an FDA-authorized heart-health claim at 7 g/day of soluble fiber. Probiotics are Grade B overall but earn a Grade A for one narrow use: preventing antibiotic-associated diarrhea with specific strains like Saccharomyces boulardii and Lactobacillus rhamnosus GG. Digestive enzymes and bovine colostrum are Grade B, and trendy Akkermansia is only Grade C — its metabolic benefit mostly showed up in people already low in the bacterium, and the live US product is dosed far below the clinical trials. So the honest answer is psyllium husk.
I just want less bloating — what should I actually take, and is Akkermansia worth it?
Start with the unglamorous option: psyllium husk is Grade A for constipation and Grade B for global IBS symptoms, though you should build the dose up slowly with plenty of water to avoid gas. Probiotics are Grade B for IBS symptoms including bloating, but the effect is strain-specific, so a labeled strain like Lactobacillus rhamnosus GG (Culturelle) beats a vague multi-strain blend. Digestive enzymes are only Grade C for general bloating in healthy people — they hit Grade A only for a diagnosed deficiency, like lactase for lactose intolerance. Akkermansia isn't where a beginner should start: it's Grade C, its benefit was largely conditional on already having low gut levels, and the live US capsules are orders of magnitude below the pasteurized dose used in the trials.
When the evidence changes, we’ll tell you.
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Medical disclaimer. The information on this site is provided for educational purposes only and is not intended as medical advice. It does not constitute a diagnosis, treatment plan, or recommendation for any specific health condition. Always consult a qualified healthcare professional before making changes to your supplement regimen, diet, or lifestyle — especially if you are pregnant, nursing, taking medications, or managing a medical condition.
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