An infant formula with large, milk phospholipid-coated lipid droplets containing a mixture of dairy and vegetable lipids supports adequate growth and is well tolerated in healthy, term infants

BACKGROUND: Lipid droplets in human milk have a mode diameter of ∼4 μm and are surrounded by a native phospholipid-rich membrane. Current infant milk formulas (IMFs) contain small lipid droplets (mode diameter ∼0.5 μm) primarily coated by proteins. A concept IMF was developed mimicking more closely the structure and composition of human milk lipid droplets.

OBJECTIVES: This randomized, controlled, double-blind equivalence trial evaluates the safety and tolerance of a concept IMF with large, milk phospholipid-coated lipid droplets (mode diameter 3-5 μm) containing vegetable and dairy lipids in healthy, term infants.

METHODS: Fully formula-fed infants were enrolled up to 35 d of age and randomly assigned to 1 of 2 formulas until 17 wk of age: 1) Control IMF with small lipid droplets containing vegetable oils (n = 108); or 2) Concept IMF with large, milk phospholipid-coated lipid droplets comprised of 48% dairy lipids (n = 115). A group of 88 breastfed infants served as reference. Primary outcome was daily weight gain during intervention. Additionally, number and type of adverse events, growth, and tolerance parameters were monitored.

RESULTS: Equivalence of daily weight gain was demonstrated (Concept compared with Control IMF: -1.37 g/d; 90% CI: -2.71, -0.02; equivalence margin ± 3 g/d). No relevant group differences were observed in growth, tolerance and number, severity, or relatedness of adverse events. We did observe a higher prevalence of watery stools in the Concept than in the Control IMF group between 5 and 12 wk of age (P < 0.001), closer to the stool characteristics observed in the breastfed group.

CONCLUSIONS: An infant formula with large, milk phospholipid-coated lipid droplets containing dairy lipids is safe, well tolerated, and supports an adequate growth in healthy infants. This trial was registered in the Dutch Trial Register (www.trialregister.nl) as NTR3683.