Differential Growth Patterns Among Healthy Infants Fed Protein Hydrolysate or Cow-Milk Formulas

Abstract

WHAT'S KNOWN ON THIS SUBJECT:The different classes of formulas, and different brands within each class, vary in composition and flavor profiles, both of which may influence feeding and growth patterns. Because recent evidence suggests that, relative to intact proteins, hydrolyzed proteins are absorbed and metabolized in a way that promotes greater satiation, we conducted a randomized study on healthy, formula-fed infants to determine whether growth patterns and feeding behaviors differ on the basis of formula type. WHAT THIS STUDY ADDS:Not all formulas are alike. On the basis of World Health Organization standards, z-score trajectories indicate that cow-milk formula-fed infants' weight gain was accelerated, whereas protein-hydrolysate formula-fed infants' weight gain was normative.abstract OBJECTIVE: Infant formulas differ considerably in composition and sensory profiles. In this randomized study, we examined whether healthy infants fed an extensively protein hydrolysate formula (PHF) would differ in feeding behavior and growth from those fed cow-milk formula (CMF). PATIENTS AND METHODS: Infants were randomly assigned to be fed CMF or PHF between 0.5 and 7.5 months of age. Each month for 7 months, infants were weighed and measured and then videotaped while being fed their assigned formula. Anthropometric z scores were calculated by using World Health Organization growth standards. Multilevel linear growth and piecewise mixed-effects models compared trajectories for growth measures and formula acceptance. RESULTS: When compared with infants fed CMF, infants fed PHF had significantly lower weight-for-length z scores across ages 2.5 to 7.5 months. There were no differences in length-for-age z scores, which indicate that group differences resulted from gains in weight, not length. Infants fed PHF also had significantly slower weight gain velocity compared with infants fed CMF. During the monthly assessments, PHF-fed infants consumed less formula to satiation than did CMF-fed infants across the study period. Maternal ratings of infants' acceptance of the formula did not differ at any age. CONCLUSIONS: z-score trajectories indicate that CMF-fed infants' weight gain was accelerated, whereas PHF-fed infants' weight gain was normative. Whether such differences in growth are because of differences in the protein content or amino acid profile of the formulas and, in turn, metabolism is unknown. Research on the long-term consequences of these early growth differences is needed. This trial has been registered at www.clinicaltrials.gov (identifier NCT00994747).

Protein needs early in life and long-term health

“…Mennella et al (30) found that infants randomly assigned to an infant formula with hydrolyzed cow-milk protein, which has a high content of FAAs, ingested less formula compared with those receiving a normal cow-milkbased infant formula and had a growth pattern closer to that of breastfed infants. In another study, glutamate, one of the most abundant FAAs in hydrolyzed infant formula, was added to a cow-milk whole-protein infant formula (31).…”

Biological Determinants Linking Infant Weight Gain and Child Obesity: Current Knowledge and Future Directions

“…Hydrolyzed protein may be more easily absorbed, metabolized differently, and exert different satiety responses than the modified cow's milk protein of standard formulas. A recent study that randomized healthy infants to receive either standard (cow's milk based) or hydrolyzed formula from 0.5 to 7.5 mo found higher WAZ starting at 3.5 mo, and higher WLZ starting at 2.5 mo among infants receiving standard formula, but no differences in LAZ (104). Individual amino acid composition may affect infant metabolism as well.…”

Early Origins of Overeating: Tracking Between Early Food Habits and Later Eating Patterns

“…Finally, mode of milk feeding may also be associated with growth curves: breastfed babies are less likely to be overweight or obese at 4 years than formula-fed babies [9]. The type of formula may also matter in relation to growth since in an experimental study, weight gain at ages 2.5 to 7.5 months in infants fed an extensively hydrolyzed protein formula was more normative than that of infants fed cow's milk formula [14]. However, a recent epidemiological report did not show a significant impact of type of formula used and growth at 4 months [15].…”