The Preventive Effect of Lactoferrin-Containing Yogurt on Gastroenteritis in Nursery School Children—Intervention Study for 15 Weeks

To evaluate the effects of bovine lactoferrin (LF)-containing yogurt on gastroenteritis in nursery school children during the winter season, we conducted a randomized prospective study. A total of 1296 children were randomized into a group in which LF was provided in yogurt (LF group, n = 661) and a non-LF consumption group (control group, n = 635). The LF group was given LF-containing yogurt (100 mg/day) on all 5 weekdays for approximately 15 weeks, and the control group consumed fruit jelly instead of the yogurt. The final totals of 578 children as the LF group and 584 as the control group were analyzed. The total number of children who were absent from school due to vomiting was significantly lower in the LF group compared to the control, accounting for ≥3 days in any week: 10/234 (4.3%) vs. 49/584 (8.4%), respectively; p = 0.04. Regarding the relationship between absences due to vomiting and the consumption of the LF-containing yogurt, the adjusted odds ratio for absence due to vomiting was 2.48 (95% CI: 1.19–5.14) in the LF children who consumed LF-containing yogurt ≤2 days/week compared to the LF children who consumed the yogurt ≥ 3 days/week. The consumption of LF-containing yogurt (100 mg/day) for ≥3 days/week might help alleviate the symptom of vomiting in nursery school children during the winter.