digestive · Outcome
Absence of bloating, gas, abdominal pain, and stool irregularity. Subjective but high-impact, daily comfort and energy track gut state closely.
How to measure: Symptom diary (frequency of bloating, gas, pain on a 0-10 scale). Bristol stool chart for stool form. SIBO breath test or stool calprotectin if symptoms persist.
Three levers, one stack. Each works through a different mechanism. They compound.
55% less GI distress
10-30B CFU multi-strain (or strain-specific where indicated) · Daily with food, ideally morning
Evidence
Effect size
Research
95 papers
range 16–81 · n=14 quantitative claims
“Multi-species synbiotic supplementation reduced bloating and gas symptoms compared to placebo, with 72.3% of participants reporting never/rarely experiencing bloating versus 55.9% in the placebo group.”
Why: Effect is strain-specific. Bifidobacterium infantis 35624 has the strongest IBS evidence; Lactobacillus rhamnosus GG for antibiotic-associated diarrhea. Generic 'probiotic' is a coin flip; pick a studied formulation.
Evidence pending
25-35 g fiber daily, mixed soluble and insoluble · Spread across meals
Evidence
Effect size
Research
None
Evidence pending
150-250 ml daily · Breakfast or snack
Evidence
Effect size
Research
None
More strain diversity than yogurt. Most people tolerate kefir even when they react to milk because lactose is largely fermented out.
Everything we found, ranked by how strongly we recommend it. Tap any to see the studies.
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Every pick has two signals. They answer different questions and we never bundle them into one number.
Effect size
How big is the change on gut comfort, in the units that matter for this outcome.
Confidence
How sure are we the effect is real for gut comfort, given the studies we have.
For every pick, the “papers” number is how many studies we've cataloged that test this entity for gut comfort. “Favorable” means the study reported the direction you want.
The tier badge (S, A, B…) on the entity itself is its overall research confidence across all outcomes. It's the same letter wherever you see this entity on the site, not specific to gut comfort.
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Why: Ramp slowly (5 g per week) to avoid worsening symptoms. People with IBS-D may need to start with soluble fiber only. Whole food first, supplements second.