Effect of Partially Hydrolyzed, Whey-based Infant Formulas on Growth and Tolerability in Healthy Term Infants

This study evaluates the growth and tolerability of partially hydrolyzed, whey-based infant formulas in healthy, full-term babies who are exclusively formula-fed. Partially hydrolyzed formulas break down the milk proteins into smaller pieces, which can make them easier to digest and potentially better tolerated — reducing symptoms like fussiness, gas, and spit-up compared to standard formulas. This research aims to confirm that these formulas support normal infant growth while being gentle on developing digestive systems. Eligible infants must be born at or after 37 weeks of gestation, weigh between 2.5 and 4.5 kg at birth, be less than 28 days old at enrollment, be singletons, and have already stopped breastfeeding at their mother's own decision. Infants with metabolic diseases, significant birth defects, known cow's milk protein allergy or lactose intolerance, or those already enrolled in another trial are excluded. Participants will be fed the assigned formula and followed with regular measurements of weight, length, and head circumference, along with parent-reported digestive tolerance. This research matters because the first months of life are a critical window for growth and gut microbiome development, and ensuring infant formula options are both nutritionally complete and well-tolerated supports healthy foundations for lifelong health.