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Head-to-head evidence comparison — which supplement is right for you?
Lactoferrin vs Vitamin D3: Vitamin D3 has the stronger overall evidence (7.5 vs 6.3/10); 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.
Vitamin D3 wins 3 of 3 categories. Both are solid choices — the best pick depends on your specific goals.
Verdict
Mostly mechanism / observational
1 of 1 studies with measurable effects showed benefit.
Top outcomes
Verdict
Probably helps
18 of 30 studies with measurable effects showed benefit.
Top outcomes
Shared outcomes (1)
Outcomes where both Lactoferrin and Vitamin D3 have evidence — compare verdict strength side-by-side.
200–300 mg daily for adults; 100–200 mg/day for children
30–60 minutes before breakfast, Between meals on an empty stomach
Bovine lactoferrin capsule or powder (≥95% purity)
2000-4000 IU daily
Morning with breakfast
D3 (cholecalciferol) softgel or liquid
4–8 weeks of use
4–8 weeks
4–8 weeks
6–12 weeks
4-8 weeks
4-8 weeks
2-4 weeks
4-8 weeks
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
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 was non-inferior to ferrous sulfate for increasing hemoglobin and serum ferritin
Vitamin D supplementation vs. placebo and incident type 2 diabetes in an ancillary study of the randomized Vitamin D and Omega-3 Trial
Nature communications (2025) · Meta analysis · n=5205
Mean body mass index (BMI) was 27.5 kg/m2 (SD = 5.3), with 51% female and 17% Black race/ethnicity.
Vitamin D Supplementation for Patients with Dysmenorrhoea: A Meta-Analysis with Trial Sequential Analysis of Randomised Controlled Trials
Nutrients (2024) · Meta analysis · n=687
TSA revealed that the current RCTs provide sufficient information.
Vitamin D and respiratory tract infections
BMJ (2017) · Meta analysis · n=11321
12% reduction in respiratory infections overall
Based on multiple meta-analyses showing OR 0.78 for RTI reduction. Effect more pronounced in children and preterm infants. Conservative estimates due to heterogeneity in populations studied.
Meta-analysis showed 12% overall reduction in respiratory infections, with greater benefits in severely deficient individuals. Daily dosing more effective than bolus. Conservative estimate assumes most users not severely deficient.
AI-estimated from published studies. Interpret as directional guidance.
Vitamin D3 has a higher evidence score (7.5/10 vs 6.3/10) and wins in 3 of 3 categories.
Both Lactoferrin and Vitamin D3 score equally (92) for support immune system.
No known interactions between Lactoferrin and Vitamin D3 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.