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Head-to-head evidence comparison — which supplement is right for you?
AREDS2 Formula vs Saccharomyces Boulardii: Saccharomyces Boulardii has the stronger overall evidence (8.5 vs 7/10); the best pick depends on your goals. Take the 60-second quiz for a pick tailored to your goals.
Saccharomyces Boulardii wins 3 of 3 categories. Both are solid choices — the best pick depends on your specific goals.
Verdict
Mostly mechanism / observational
Top outcomes
Verdict
Likely helps
13 of 15 studies with measurable effects showed benefit.
Top outcomes
Shared outcomes (1)
Outcomes where both AREDS2 Formula and Saccharomyces Boulardii have evidence — compare verdict strength side-by-side.
One AREDS2 daily regimen, usually split into two servings: vitamin C 500 mg, vitamin E 400 IU, lutein 10 mg, zeaxanthin 2 mg, zinc 80 mg (as zinc oxide) and copper 2 mg (as cupric oxide)
with-meals
A product matching the AREDS2 composition exactly: vitamin C 500 mg, vitamin E 400 IU, lutein 10 mg, zeaxanthin 2 mg, zinc 80 mg, copper 2 mg
250-500mg (5-10 billion CFU) daily
With or without food, At least 2 hours away from antifungals
Capsules (lyophilized)
Years — average follow-up was 6.3 years
Years
Long-term
Years
During use
1-3 days
1-2 weeks
Lutein + zeaxanthin and omega-3 fatty acids for age-related macular degeneration: the Age-Related Eye Disease Study 2 (AREDS2) randomized clinical trial.
JAMA (2013) · Rct · n=4203
Primary analysis was NULL: lutein/zeaxanthin HR 0.90 (98.7% CI 0.76-1.07, P=.12); DHA+EPA HR 0.97 (0.82-1.16, P=.70); both together HR 0.89 (0.75-1.06, P=.10)
A randomized, placebo-controlled, clinical trial of high-dose supplementation with vitamins C and E, beta carotene, and zinc for age-related macular degeneration and vision loss: AREDS report no. 8.
Arch Ophthalmol (2001) · Rct · n=3640
Antioxidants plus zinc vs placebo for advanced AMD: OR 0.72 (99% CI 0.52-0.98). Zinc alone OR 0.75 (0.55-1.03); antioxidants alone OR 0.80 (0.59-1.09) — neither significant on its own
Long-term Outcomes of Adding Lutein/Zeaxanthin and ω-3 Fatty Acids to the AREDS Supplements on Age-Related Macular Degeneration Progression: AREDS2 Report 28.
JAMA Ophthalmol (2022) · Cohort · n=3882
10-year lung cancer odds ratio: 1.82 (95% CI 1.06-3.12, P=.02) for beta-carotene assignment vs 1.15 (0.79-1.66, P=.46) for lutein/zeaxanthin
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.
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 7/10) and wins in 3 of 3 categories.
No known interactions between AREDS2 Formula and Saccharomyces Boulardii have been documented in our database. However, always consult a healthcare provider before combining supplements.
The right pick depends on your goals. Answer a few quick questions for a personalised recommendation — or dig into the full evidence on each.