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Head-to-head evidence comparison — which supplement is right for you?
Iron vs VSL#3 / Visbiome: Iron has the stronger overall evidence (9 vs 6.5/10); the best pick depends on your goals. Take the 60-second quiz for a pick tailored to your goals.
Iron wins 2 of 3 categories. Both are solid choices — the best pick depends on your specific goals.
Verdict
Likely helps
11 of 15 studies with measurable effects showed benefit.
Top outcomes
Verdict
Mostly mechanism / observational
Top outcomes
18-45mg elemental iron for deficiency (varies by severity)
On empty stomach if tolerated, Away from tea, coffee, dairy
Ferrous bisglycinate (gentle, well-absorbed) or iron protein succinylate
Prevention and maintenance are DIFFERENT doses and are often conflated. Preventing the first onset of acute pouchitis used 900 billion CFU/day (1 sachet). Maintaining remission in established chronic or refractory pouchitis — where the effect size is largest — used 6 g/day, which at 5 x 10^11 viable bacteria per gram is about 3 trillion CFU/day, in both maintenance trials. As a ulcerative colitis add-on, 3.6 trillion CFU daily; the active-UC induction trial went highest at 3.6 trillion CFU TWICE daily (7.2 trillion/day), and the paediatric trial lowest at 450 billion/day weight-based
any
Refrigerated sachet of the De Simone Formulation
2-4 weeks
4-8 weeks
4-12 weeks
9-12 months
12 months
8-12 weeks
n/a
Daily oral iron supplementation during pregnancy
The Cochrane database of systematic reviews (2024) · Meta analysis · n=48971
There is probably little to no difference in maternal death (2 versus 4 events, RR 0.57, 95% CI 0.12 to 2.69; 3 trials, 14,060 women; moderate-certainty evidence).
The Prevalence of Anemia among Pregnant Women in China: A Systematic Review and Meta-Analysis
Nutrients (2024) · Meta analysis · n=722
The results showed that the prevalence of anemia, ID, and IDA among pregnant women in China were 30.7% (95% CI: 26.6%, 34.7%), 45.6% (95% CI: 37.0%, 54.2%), and 17.3% (95% CI: 13.9%, 20.7%), respectively.
Treatment for women with postpartum iron deficiency anaemia
The Cochrane database of systematic reviews (2024) · Meta analysis · n=572
Intravenous iron versus oral iron supplementation The evidence is very uncertain about the effect of intravenous iron on mortality (risk ratio (RR) 2.95, 95% confidence interval (CI) 0.12 to 71.96; P = 0.51; I² = not applicable; 3 RCTs; 1 event; 572 women; very low-certainty evidence).
Treatment and prevention of pouchitis after ileal pouch-anal anastomosis for chronic ulcerative colitis.
Cochrane Database Syst Rev (2019) · Meta analysis
Chronic pouchitis maintenance: 85% (34/40) maintained remission at 9-12 months vs 3% (1/36) placebo — RR 20.24 (95% CI 4.28-95.81), low certainty
Oral bacteriotherapy as maintenance treatment in patients with chronic pouchitis: a double-blind, placebo-controlled trial.
Gastroenterology (2000) · Rct · n=40
Relapse in 3/20 (15%) on the probiotic vs 20/20 (100%) on placebo, P<0.001
Once daily high dose probiotic therapy (VSL#3) for maintaining remission in recurrent or refractory pouchitis.
Gut (2004) · Rct · n=36
Remission maintained at 1 year in 17/20 (85%) vs 1/16 (6%) placebo, p<0.0001
Based on meta-analyses showing hemoglobin improvements of 2.01-5.30 g/dL in iron deficient populations. Higher doses show diminishing returns with increased GI side effects. Effectiveness varies significantly by baseline iron status and form used.
AI-estimated from published studies. Interpret as directional guidance.
Iron has a higher evidence score (9/10 vs 6.5/10) and wins in 2 of 3 categories.
No known interactions between Iron and VSL#3 / Visbiome have been documented in our database. However, always consult a healthcare provider before combining supplements.
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The right pick depends on your goals. Answer a few quick questions for a personalised recommendation — or dig into the full evidence on each.