Antigen-reduced infant formulas versus human milk: growth and metabolic parameters in the first 6 months of life

OBJECTIVE: To compare growth and metabolic parameters of infants fed special formulas for atopy prevention to breast-fed infants. METHODS: Eighty-two infants with family history of IgE-mediated diseases completed a 6-month nutritional follow-up within a clinical trial to assess the effectiveness of the dietary intervention in preventing atopy. Infants were subdivided according to the type of milk feeding from the end of the first month of life up to sixth month: human milk (HM) group (29 infants); soy formula (SF) group (15 infants); whey-based low-degree hydrolysate (WHy) group (15 infants); casein-based high-degree hydrolysate (CHy) group (13 infants); soy plus collagen-based high-degree hydrolysate group (10 infants). Anthropometric indices were determined at 0, 3 and 6 months of life and a fasting blood sample for hematochemical parameters was obtained at 5 months of life before beginning the introduction of solid foods. RESULTS: Lower values of body mass index and higher blood urea nitrogen were displayed by the CHy group at 3 months. Plasma aminoacidograms showed higher essential amino acids (AA)/total AA in SF, WHy and CHy groups but lower branched chain AA/essential AA in all formula-fed infants in comparison with the HM group. CONCLUSIONS: Special formulas (in particular high-degree protein hydrolysates) should be carefully evaluated when used for prolonged periods of time in healthy infants at familial risk of atopy.