The evaluation of secondary parameters of a prospective, randomised, controlled, multicentre intervention trial aimed to analyse gastrointestinal tolerance of an infant formula manufactured from extensively hydrolysed whey protein (eHF) compared to intact cow's milk protein (control formula, CF) in healthy term infants. Infants ≤ 25 days of age, who were exclusively formula-fed, were randomised to receive eHF or CF for at least three months up to 120 days of age. An exclusively breastfed reference group (BF) was included for descriptive comparison. Infants' gastrointestinal tolerance was evaluated based on stool parameters, the Amsterdam Infant Stool Scale (AISS), the Infant Gastrointestinal Symptom Questionnaire (IGSQ), and sleeping patterns. Of 359 infants included, 297 randomised (eHF: n = 149, CF: n = 148) and 41 BF infants completed the study per protocol. All tolerance parameters were comparable between eHF and CF. Stool was predominantly soft and yellow in colour. Stool was more frequently green in eHF than CF. BF infants had more frequent stools, which were mainly watery or soft and yellow, and comparable IGSQ scores (descriptive). Irrespective of group, all gastrointestinal and sleep parameters showed signs of maturation with increasing age. In conclusion, eHF showed gastrointestinal tolerance as good as CF in healthy infants. Both formulae were well-tolerated.
Keywords: IGSQ; breastfed; digestibility; extensively hydrolysed whey protein; gastrointestinal tolerance; infant formula; infant nutrition; protein hydrolysate; sleeping; stool characteristics.