OBJECTIVE:
Children are vulnerable to diet inadequacies, which may affect immune function. Our objective was to determine if a follow-up formula (FUF) containing DHA, the prebiotics PDX and GOS, and yeast β-glucan affects incidence of respiratory infections and diarrheal disease in healthy children.

METHODS:
In a double-blind, randomized, controlled, prospective trial, 3-4 year old children were fed 3 servings per day of either a FUF with 25 mg DHA, 1.2 g PDX/GOS, and 8.7 mg yeast β-glucan per serving or an unfortified, cow's milk-based beverage (control) for 28 weeks. Fecal and blood samples were collected to assess immune markers and iron/zinc status. Incidence of acute respiratory infections (ARI), diarrheal disease, and antibiotic treatment were obtained from medical records.

RESULTS:
The FUF group had fewer episodes and shorter duration of ARI (mean days [SE]; control = 4.3 [0.2]; FUF = 3.5 [0.2]; P = .007), less antibiotic use (n [%]; control = 21 [14%]; FUF = 8 [5%]; P = .01), and fewer missed days of day care due to illness. No diarrheal disease was diagnosed in either group. The FUF group had higher interleukin-10 and white blood cell count at the end of the study. There were no differences in hemoglobin, serum ferritin and zinc, or fecal secretory immunoglobulin A.

CONCLUSIONS:
Daily consumption of a FUF was associated with fewer episodes and shorter duration of ARI, as well as less antibiotic use. The children who consumed the FUF had increased interleukin-10 and white blood cells, suggesting an antiinflammatory mechanism and/or an increase of effector immune cells.