Objective: Intestinal microbiota plays an important role in the prevention of certain diseases during
the pediatric years. Thus, there is an increasing interest in the addition of probiotics to infant
formulas. The aim of this study was to evaluate the safety of a follow-on formula with Lactobacillus
salivarius CECT5713 in 6-mo-old children.
Methods: The antibiotic susceptibility of L. salivarius CECT5713 was analyzed by a dilution method.
A double-blinded, randomized, placebo controlled study was performed. Children (n ¼ 80) were
distributed in two groups and consumed the formula supplemented or not with probiotics (2 106
colony-forming units [cfu]/g) during 6 mo. Fecal samples were collected at enrollment, at 3 mo,
and at the end of trial. Clinical and anthropometric evaluations were performed. Depending on the
variable, one-way or two-way repeated measures analysis of variance were used for the statistical
analysis.
Results: The antibiotic susceptibility profile of the strain resulted as safe. No adverse effects associated
with the consumption of the probiotic formula were reported. In addition, clinical parameters
did not differ between groups. Consumption of the probiotic supplemented formula led to an
increase in the fecal lactobacilli content (7.6 0.2 versus 7.9 0.1 log cfu/g, P < 0.05). Lactobacillus
salivarius CECT5713 was detected in the feces of volunteers from the probiotic group. Probiotic
consumption induced a significant increase in the fecal concentration of butyric acid at 6 mo.
Conclusion: Thus, a follow-on formula with L. salivarius CECT5713 is safe and well tolerated in
6-mo-old infants.