A randomized, double-blinded, placebo controlled parallel-group comparative study by Oda et al. published in 2020 evaluated the efficacy of bovine lactoferrin (bLf) on the prevalence and duration of infectious diseases in adults during the Japanese summer. Healthy adults aged 20-65 years were enrolled in the study and randomised into three groups. 290 people completed study. The control group received a placebo tablet. The second group received tablets with 200mg of lactoferrin. The third group consumed tablets 600mg of lactoferrin a day.

After 12 weeks the duration of total infectious diseases was shorter in the groups consuming 200mg or 600mg than in the placebo group. Of more importance those adults consuming 600mg of lactoferrin a day for 12 weeks experienced a statistically significant (p=0.036) shortened duration of a summer cold.

Oda H et al., Effects of lactoferrin on infectious diseases in Japanese summer: A randomized, double-blinded, placebo-controlled trial, Journal of Microbiology, Immunology and Infection, https://doi.org/10.1016/j.jmii.2020.02.010