Benefits
Immune function: stronger results in children than in adults
A pooled analysis of 25 lactoferrin studies found fewer respiratory infections in infants and children (odds ratio 0.78) but no change in adults (odds ratio 1.00). In adults, lactoferrin lowered the inflammatory marker IL-6 but did not change natural killer cell activity or C-reactive protein. These studies tested lactoferrin in general, not Bioferrin specifically.
Days of illness in healthy adults in one 12-week trial
In a placebo-controlled trial of 310 healthy Japanese adults over a summer, 200 or 600 mg a day of lactoferrin shortened the total duration of infectious illness (2 vs 3 days), but did not change how often people got sick or their immune measures, which were the main goals. Most authors worked for the lactoferrin maker.
Seasonal immune support with a lactoferrin and whey blend
In a 90-day placebo-controlled trial in 126 adults who often caught colds, 600 mg a day of a blend of lactoferrin and a whey immunoglobulin fraction was followed by fewer colds (48 vs 112) and fewer cold symptoms. Days sick and severity did not differ significantly. Because it was a blend, the lactoferrin effect alone is unknown.
Iron status in pregnant women with low iron
In a non-randomized study of 295 pregnant women with low iron and an inherited clotting disorder, those choosing 100 mg of bovine lactoferrin twice daily had higher hemoglobin, serum iron and ferritin than those taking ferrous sulfate, with no adverse effects versus 16.5 percent with ferrous sulfate. Both reports come from one Italian research group.
Iron stores when added to iron in children
Pooling 8 controlled trials in children, adding lactoferrin to iron raised serum ferritin slightly more than iron alone (by 3.52 micrograms per liter) but did not improve hemoglobin, serum iron or transferrin receptor levels.
Gut health in children's lactoferrin trials
A pooled analysis of trials in children found fewer children with diarrhea when given oral lactoferrin than placebo (odds ratio 0.56, 14 studies). These trials were in children, not adults, and tested lactoferrin in general rather than Bioferrin.
Mechanism of action
Iron binding
Lactoferrin is a major iron-binding protein and has been proposed as a way to carry iron for absorption. In pregnant women, the rise in blood counts with bovine lactoferrin was linked with a fall in the inflammatory marker IL-6 and a rise in prohepcidin, a precursor of the iron-regulating hormone hepcidin.
Antimicrobial and immune-modulating activity
Lactoferrin has antibacterial, antiviral and immune-modulating properties in laboratory studies, which is the rationale for testing it against infections. In adults, the measured immune effect was a lower IL-6 level, with no change in natural killer cell activity.
Clinical trials
Systematic review and meta-analysis of 25 studies of lactoferrin supplementation, 20 in adults (Berthon et al. 2022, Adv Nutr)
Infants, children and adults across the included studies.
Respiratory infection incidence fell in infants and children (odds ratio 0.78) but not in adults (odds ratio 1.00). In adults, lactoferrin lowered IL-6 but not C-reactive protein or natural killer cell cytotoxicity. The authors called the clinical studies limited.
Randomized, double-blind, placebo-controlled trial of 200 or 600 mg a day of lactoferrin for 12 weeks (Oda et al. 2021, J Microbiol Immunol Infect)
310 healthy adults at a Japanese university; 290 analysed.
Total days of infectious illness were shorter with 200 mg and 600 mg than with placebo (2 vs 3 days), and summer colds were shorter with 600 mg. The primary outcomes of how often people got sick and immune measures did not differ. Five authors were employees of Morinaga Milk Industry.
Double-blind, randomized, placebo-controlled trial of 600 mg a day of a bovine lactoferrin and whey protein immunoglobulin fraction for 90 days (Vitetta et al. 2013, Complement Ther Med)
126 adults reporting frequent colds; 90 completed 90 days.
There were 48 colds in the treatment group versus 112 with placebo, and fewer cold-related symptoms. Total days sick and cold severity were lower but not significantly. The product was a blend, not lactoferrin alone.
Systematic review and meta-analysis of 25 randomized controlled trials of oral lactoferrin in people under 18 (Mayorga et al. 2025, Biochem Cell Biol)
Newborns and children in 10 sepsis, 14 diarrhea and 8 respiratory infection studies.
Lactoferrin was associated with fewer newborns with late-onset sepsis (odds ratio 0.60) and fewer children with diarrhea (odds ratio 0.56), but not significantly fewer children with upper respiratory infections (odds ratio 0.61, confidence interval crossing 1).
Randomized, double-blind, placebo-controlled trial of 150 mg/kg a day of bovine lactoferrin from the first 72 hours of life for 4 weeks or until discharge (Plaza-Astasio et al. 2025, Nutrients)
103 very low birth weight preterm infants in a hospital setting.
Late-onset sepsis was less frequent with lactoferrin (adjusted risk ratio 0.54), with no difference in other illnesses or deaths. Some immune and antioxidant markers stayed steadier with lactoferrin. This is hospital neonatal care, not a use for a consumer supplement.
Non-randomized interventional study in which women chose 100 mg of bovine lactoferrin twice daily or 520 mg of ferrous sulfate once daily until delivery (Paesano et al. 2014, Biometals)
295 pregnant women with hereditary thrombophilia and low iron or iron deficiency anemia.
Red blood cells, hemoglobin, serum iron and ferritin were higher with lactoferrin than with ferrous sulfate, IL-6 fell with lactoferrin, and no adverse effects were seen with lactoferrin versus 16.5 percent with ferrous sulfate. Treatment was chosen by the women, not randomized.
Systematic review and meta-analysis of controlled trials comparing iron plus bovine lactoferrin with iron alone; 8 trials pooled (Zhong et al. 2026, Nutr Rev)
Children with or without anemia.
Adding lactoferrin raised serum ferritin by 3.52 micrograms per liter more than iron alone, with no significant effect on hemoglobin, serum iron or serum transferrin receptor.