Abstract
Background: Medium- and long-chain triacylglycerols (MLCTs) and sn-2 palmitate constitute approximately 70~80% of total breast milk fat. The structured lipid MLCTs and sn-2 palmitate, mimicking human milk, have demonstrated improvement in lipid absorption and energy metabolism in vitro and in animal experiments. However, clinical trials on infant formula supplied with MLCTs and sn-2 palmitate have yet to be conducted. Objectives: This study was designed to evaluate the effects on growth and lipid absorption of a novel formula with structured lipid MLCTs and sn-2 palmitate on healthy infants born at term. Methods: Infants were enrolled at 30 d postpartum and assigned to three groups based on their feeding conditions: (1) a novel formula with MLCTs and sn-2 palmitate (Novel-F group, n = 65); (2) a control formula with vegetable oils and no structured lipids (Contr-F group, n = 46); or (3) breastfeeding (BF group, n = 66). Growth measurements (including weight, length, and head circumference), stool characteristics, and fecal lipid composition (both soap and non-soap fatty acids) were analyzed at both baseline (30 d postpartum) and endline visits (90 d postpartum). Results: The Novel-F group had significantly higher weight gains (2195 ± 595 g) during the intervention compared to the Contr-F group (1897 ± 483 g) but similar weight gains to the BF group (2081 ± 614 g), with the changes in Z(w/a) following a similar pattern. Z(l/a) increased in the Novel-F group (0.04, (95% CI: -0.21 to 0.28)) and decreased in both the Contr-F (-0.23 (95% CI: -0.52 to 0.06)) and BF groups (-0.20 (95% CI: -0.44 to 0.05)). The stools of infants in the Novel-F group had similar undigested triacylglycerols and total fatty acids compared to breastfed infants but had significantly lower levels than infants fed with the control formula at both baseline and endline visits. Conclusions: The novel infant formula with MLCTs and sn-2 palmitate is safe and well tolerated, and supports adequate weight gain and improves lipid absorption.