Effects of infant formula supplemented with prebiotics compared with synbiotics on growth up to the age of 12 mo: a randomized controlled trial.

BACKGROUND: Growth is an essential outcome measure for evaluating the safety of infant formulas (IF). We investigated the effects of consumption of IF supplemented with prebiotics (fructooligosaccharides, FOS, and galactooligosaccharides, GOS) compared with synbiotics (FOS/GOS and Lactobacillus paracasei ssp. paracasei strain F19) on the growth of healthy infants.

METHODS: 182 full-term infants who were weaned completely from breast milk to IF at 28 d of age were randomly assigned to receive prebiotic- or synbiotic-supplemented, otherwise identical, IF until 6 mo of age (intervention period).

RESULTS: A total of 146 (80%) infants were included in the intention-to-treat analysis at 6 mo. Anthropometric parameters were similar in the two groups during the intervention and follow-up period until 12 mo of age. Compared with the prebiotic group, a significant reduction in the cumulative incidence of lower respiratory tract infections was found in the synbiotic group; however, the confidence interval of the estimate was wide, resulting in uncertainty.

CONCLUSION: The lack of a significant difference between the formula-fed groups in growth, or the occurrence of serious adverse events, supports the safety of using IF supplemented with synbiotics. Further studies are needed to evaluate the effects of such formula on lower-respiratory tract infections.