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Head-to-head evidence comparison — which supplement is right for you?
Saccharomyces Boulardii vs Shiitake: they're closely matched on evidence (8.5 vs 4.5/10); they're alternatives for support immune system — the best pick depends on your goals. Take the 60-second quiz for a pick tailored to your goals.
Saccharomyces Boulardii and Shiitake are closely matched across evidence, studies, and safety.
Verdict
Likely helps
4 of 4 studies with measurable effects showed benefit.
Top outcomes
Verdict
Too few graded studies
1 of 1 studies with measurable effects showed benefit.
Top outcomes
Shared outcomes (1)
Outcomes where both Saccharomyces Boulardii and Shiitake have evidence — compare verdict strength side-by-side.
250-500mg (5-10 billion CFU) daily
With or without food, At least 2 hours away from antifungals
Capsules (lyophilized)
5-15g dried mushroom or 1-3g extract daily
With meals, Divided doses if using higher amounts
Shiitake extract (standardized to polysaccharides)
During use
1-3 days
1-2 weeks
4 weeks
8-12 weeks
4-8 weeks
Efficacy and safety of Saccharomyces boulardii as an adjuvant therapy for the eradication of Helicobacter pylori: a meta-analysis
Frontiers in cellular and infection microbiology (2025) · Meta analysis · n=5036
Meta-analysis of 19 studies with 5,036 people with H. pylori infection, adding S. boulardii to standard eradication therapy.
Probiotics for treating acute infectious diarrhoea
The Cochrane database of systematic reviews (2020) · Meta analysis · n=12127
Effect size was similar in the sensitivity analysis and marked heterogeneity persisted.
The use of probiotics and prebiotics in decolonizing pathogenic bacteria from the gut; a systematic review and meta-analysis of clinical outcomes
Gut microbes (2024) · Meta analysis · n=2871
This review aims to analyze available evidence from human-controlled trials to determine the effect size of probiotic interventions in decolonizing AMR pathogenic bacteria from the gut.
Critical Review on the Anti-Tumor Activity of Bioactive Compounds from Edible and Medicinal Mushrooms over the Last Five Years
Nutrients (2025) · Review
In recent years, the incidence rate of cancer has been on the rise all over the world, and the age of cancer patients has shown a younger trend, which seriously endangers patients' health.
Vitamin B12 sources in non-animal foods: a systematic review
Critical reviews in food science and nutrition (2023) · Systematic review
In the last decade, more sensitive method for real B12 determination was used, the liquid chromatography-electrospray ionization tandem mass spectrometry chromatograms.
Anti-Cancer Potential of Edible/Medicinal Mushrooms in Breast Cancer
International journal of molecular sciences (2023) · Review
In this article, we reviewed mushrooms showing antineoplastic activity again breast cancer cells, especially focusing on the possible bioactive compounds involved and their mechanisms of action.
Both points come from a meta-analysis of 10 randomised trials adding S. boulardii to bismuth quadruple therapy (PMID 40251486), whose dose subgroups found the same gain in eradication at 500 mg a day (RR 1.10, 95% CI 1.03 to 1.17) and 1000 mg a day (RR 1.08, 95% CI 1.03 to 1.12). Effectiveness is the relative gain in eradication in percent. Total adverse effects fell with S. boulardii (RR 0.53), so the side effect values are low. The authors recommend 500 mg a day for more than 10 days. The effect is as an add-on to antibiotics only, and doses are in mg of product, not CFU.
AI-estimated from published studies. Interpret as directional guidance.
Both Saccharomyces Boulardii and Shiitake are closely matched — the best choice depends on your specific health goals.
For support immune system, Shiitake has a higher relevance score (75 vs 60).
No documented interaction was found in the data searched. This does not establish that this exact combination is safe.
The right pick depends on your goals. Answer a few quick questions for a personalised recommendation — or dig into the full evidence on each.