Prebiotic effect of an infant formula supplemented with galacto-oligosaccharides: randomized multicenter trial

The objective of the study was to investigate the effects of a galacto-oligosaccharides (GOS)-supplemented formula on the intestinal microbiota in healthy term infants, with a specific consideration for gastrointestinal symptoms as colic, stool frequency and consistency, regurgitation.

This was a randomized, double-blind, controlled, parallel-group clinical trial performed simultaneously by 6 centers in Italy. Three groups were considered: breastfed, formula-fed, and GOS-supplemented formula-fed infants. Formula-fed infants were randomized to receive either the control or the study formula and consume the assigned formula exclusively until the introduction of complementary feeding. The nutritional composition of the 2 formulas were identical, apart from the supplemented GOS (0.4 g/100 mL) in the study formula. Four different types of bacteria were evaluated in order to assess the efficacy of GOS-supplemented formula on infants: Bifidobacterium, Lactobacillus, and Clostridium, Escherichia coli.

A total of 199 breastfed infants and 163 formula-fed infants were recruited. When considering stool frequency and consistency, GOS-supplemented formula presented normal and soft stools in the majority of episodes (89%). In the supplemented group the incidence of colic was lower with respect to the control group. A significantly lower count of Clostridium and a higher count of Bifidobacterium were found when comparing study formula and control formula in infants with colic. In children with colic the ratio between Clostridium count and Bifidobacterium and Lactobacillus count was in favor of the latter two when considering the GOS-supplemented formula group with respect to the control one.

The prebiotic-supplemented formula mimicked the effect of human milk in promoting Bifidobacterium and Lactobacillus growth and in inhibiting Clostridium growth, resulting in a significantly lower presence of colic.