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Head-to-head evidence comparison — which supplement is right for you?
Saccharomyces Boulardii wins 2 of 3 categories. Both are solid choices — the best pick depends on your specific goals.
Verdict
Likely helps
6 of 8 studies with measurable effects showed benefit.
Top outcomes
Verdict
Likely helps
13 of 15 studies with measurable effects showed benefit.
Top outcomes
Shared outcomes (1)
Outcomes where both L-Lysine and Saccharomyces Boulardii have evidence — compare verdict strength side-by-side.
500-3000mg daily; higher for active outbreaks
Empty stomach for better absorption, Divided doses throughout day, Away from high-arginine foods
L-Lysine HCl (capsules or powder)
250-500mg (5-10 billion CFU) daily
With or without food, At least 2 hours away from antifungals
Capsules (lyophilized)
2-4 weeks prevention; acute treatment faster
4-8 weeks
Ongoing
During use
1-3 days
1-2 weeks
The Impact of Amino Acids on Postprandial Glucose and Insulin Kinetics in Humans: A Quantitative Overview
Nutrients (2020) · Systematic review · n=55
Oral ingestion of most individual AAs induced an insulin response, but did not alter glucose concentrations in healthy participants.
Nutraceuticals and phytoceuticals in the treatment of schizophrenia: a systematic review and network meta-analysis "Nutra NMA SCZ"
Molecular psychiatry (2025) · Meta analysis · n=50
Change (Standardized Mean Difference = SMD) in total symptomatology and acceptability (Risk Ratio = RR) were co-primary outcomes.
A Dietary Supplement in the Management of Patients with Lumbar Osteochondrosis: A Randomized, Double-Blinded, Placebo-Controlled Study
Nutrients (2024) · Rct
Despite no significance regarding the distribution of Pfirrmann grade changes (improvement, no change, worsening; p = 0.259), in the supplement group, one patient achieved a three-grade improvement, and worsening of Pfirrmann grades were only detected in the placebo group (9.1%).
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
S. boulardii supplementation in traditional eradication therapy significantly improves the H. pylori eradication rate and reduces the total adverse effects and incidence of diarrhea, bloating, constipation, and nausea.
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.
Safety profile based on systematic review of 71 studies (n=2619). Risk analysis showed no statistically significant increase in GI symptoms (RR 1.02, 95% CI 0.96-1.07, p=0.49). Adverse events were mainly subjective GI symptoms. Short-term use up to 6g appears safe.
Based on multiple meta-analyses showing 1.1-1.6 day reduction in diarrhea duration. Effect size appears to plateau at standard therapeutic doses. Limited data on doses above 20 billion CFU.
AI-estimated from published studies. Interpret as directional guidance.
Saccharomyces Boulardii has a higher evidence score (8.5/10 vs 5.5/10) and wins in 2 of 3 categories.
For support immune system, L-Lysine has a higher relevance score (70 vs 60).
No known interactions between L-Lysine and Saccharomyces Boulardii have been documented in our database. However, always consult a healthcare provider before combining supplements.