Adequacy and safety of α-lactalbumin-enriched low-protein infant formula: A randomized controlled trial.

OBJECTIVES: The aim of this study was to demonstrate suitability and safety of an infant formula enriched with α-lactalbumin with a reduced protein content of 1.89 g protein/100 kcal. METHODS: This was a randomized, double-blind controlled trial with 80 healthy newborn infants who were assigned to receive either an isocaloric low- or high-protein content formula (1.89 versus 2.1 g/100 kcal). The low-protein content formula was enriched with α-lactalbumin. A breast-fed reference group of 40 infants was studied concurrently. Anthropometric measures were taken at inclusion, after 6 and 12 wk as well as after 6 and 12 mo of follow-up. Primary outcome was weight gain in g/d between study inclusion to 12 wk. Secondary outcomes included anthropometric measures expressed in Z-scores, mean formula consumption, and caloric intake as well as food tolerance. RESULTS: Fifty-two infants in the formula group (low protein: 26, high protein: 26) and 32 in the breast-fed reference group completed the 3-mo intervention period. There was no difference in weight gain among feeding groups at the end of the intervention period. Mean weight gain in g/d was 32 in the low-protein, 31 in the high-protein, and 33 in the breast-fed reference group. No significant difference was found between study groups in Z-scores for weight, length, head circumference, weight-for-length, or body mass index nor for fat percentage at end of intervention and after follow-up. CONCLUSION: α-lactalbumin-enriched formula with a protein content of 1.89 g protein/100 kcal is safe and supports adequate growth.

Infant formula with cow's milk fat and prebiotics affects intestinal flora, but not the incidence of infections during infancy in a double-blind randomized controlled trial.

BACKGROUND: The postnatal intestinal colonization of human milk-fed and formula-fed infants differs substantially, as does the susceptibility to infectious diseases during infancy. Specific ingredients in human milk, such as prebiotic human milk oligosaccharides and a specifically structured fat composition with high proportion of beta-palmitic acid (beta-PA) promote the growth of intestinal bifidobacteria, which are associated with favorable effects on infants' health. The present study investigates whether addition of prebiotic galactooligosaccharides (GOS) in combination with higher amounts of beta-PA from cow's milk fat in infant formula positively affects gut microbiota and the incidence of infections in formula-fed infants. METHODS: In a double-blind controlled trial, formula-fed infants were randomly assigned to either receive an experimental formula containing a higher proportion of beta-PA (20-25%) from natural cow's milk fat, and a prebiotic supplement (0.5 g GOS/100 ml), or a standard infant formula with low beta-PA (< 10%), without prebiotics. A breast-fed reference group was also enrolled. After 12 weeks, fecal samples were collected to determine the proportion of fecal bifidobacteria. The number of infections during the first year of life was recorded. RESULTS: After 12 weeks, the proportion of fecal bifidobacteria was significantly higher in infants receiving formula with high beta-PA and GOS compared to control, and was similar to the breast-fed group (medians 8.8%, 2.5%, and 5.0% respectively; p < 0.001). The incidence of gastrointestinal or other infections during the first year of life did not differ between groups. CONCLUSIONS: The combination of higher amounts of beta-PA plus GOS increased significantly the proportion of fecal bifidobacteria in formula-fed infants, but did not affect the incidence of infections. TRIAL REGISTRATION: The study protocol was registered with Clinical Trials (Protocol Registration and Results System Trial ID: NCT01603719 ) on 05/15/2012 (retrospectively registered).