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Head-to-head evidence comparison — which supplement is right for you?
L. casei Shirota vs Lactoferrin: Lactoferrin has the stronger overall evidence (6.3 vs 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.
Lactoferrin wins 2 of 3 categories. Both are solid choices — the best pick depends on your specific goals.
Verdict
Too few graded studies
Top outcomes
Verdict
Too few graded studies
1 of 1 studies with measurable effects showed benefit.
Top outcomes
Shared outcomes (1)
Outcomes where both L. casei Shirota and Lactoferrin have evidence — compare verdict strength side-by-side.
One 65-100 mL bottle of the fermented milk drink daily, delivering roughly 6.5 x 10^9 to 1 x 10^11 CFU depending on the product. Doses across trials span this whole range with no dose-comparison study to separate them.
Any time of day
Fermented milk drink containing L. casei Shirota (Yakult), 65-100 mL daily
200–300 mg daily for adults; 100–200 mg/day for children (a typical label dose, not the dose used in the cited trials, which used 600 to 3,400 mg a day in adults, and no cited trial states a dose for children)
30–60 minutes before breakfast, Between meals on an empty stomach
Bovine lactoferrin capsule or powder (≥95% purity)
4 weeks
2 weeks
2-12 weeks
8 weeks
4–8 weeks of use
4–8 weeks
4–8 weeks
6–12 weeks
Efficacy of daily intake of Lactobacillus casei Shirota on respiratory symptoms and influenza vaccination immune response: a randomized, double-blind, placebo-controlled trial in healthy elderly nursing home residents.
Am J Clin Nutr (2012) · Rct · n=737
PRIMARY ENDPOINTS ALL NULL: no effect on days with respiratory symptoms, probability of respiratory symptoms, or post-vaccination antibody titre
Probiotics and synbiotics in chronic constipation in adults: A systematic review and meta-analysis of randomized controlled trials.
Clin Nutr (2022) · Meta analysis
Probiotics overall increased stool frequency (SMD 0.71, 95% CI 0.37-1.04, p<0.00001) — but the effect was driven by Bifidobacterium lactis, 'not mixtures of probiotics, Bacillus coagulans Unique IS2 or Lactobacillus casei Shirota'
A study into the effect of Lactobacillus casei Shirota in preventing antibiotic associated diarrhoea including Clostridioides difficile infection in patients with spinal cord injuries: a multicentre randomised, double-blind, placebo-controlled trial.
EClinicalMedicine (2021) · Rct · n=359
PRIMARY ENDPOINT NULL: antibiotic-associated diarrhoea at 30 days 45% vs 42.1% (RR 1.071, 95% CI 0.8-1.4, p=0.639)
Effect of Lactoferrin Supplementation on Inflammation, Immune Function, and Prevention of Respiratory Tract Infections in Humans: A Systematic Review and Meta-analysis.
Advances in Nutrition (2022) · Meta analysis
Lactoferrin significantly reduced IL-6 in adults (mean difference: -24.9 pg/mL; 95% CI: -41.64, -8.08 pg/mL)
Lactoferrin reduces the risk of respiratory tract infections: A meta-analysis of randomized controlled trials.
Clinical Nutrition ESPEN (2021) · Meta analysis · n=1194
Pooled analysis of RCTs showed significant reduction in respiratory tract infection risk with lactoferrin supplementation
Comparative Effects between Oral Lactoferrin and Ferrous Sulfate Supplementation on Iron-Deficiency Anemia: A Comprehensive Review and Meta-Analysis of Clinical Trials.
Nutrients (2022) · Meta analysis
Lactoferrin supplementation had better effects on serum iron (WMD: 41.44 ug/dL; p < 0.00001), ferritin (WMD: 13.60 ng/mL; p = 0.003) and hemoglobin concentration (11.80 g/dL; p < 0.00001), but a reducing effect on fractional iron absorption (WMD: −2.08%; p = 0.02) and IL-6 levels (WMD: −45.59 pg/mL; p < 0.00001) compared with ferrous sulfate.
Lactoferrin has a higher evidence score (6.3/10 vs 5/10) and wins in 2 of 3 categories.
For support immune system, Lactoferrin has a higher relevance score (92 vs 38).
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.