Long-term safety of early consumption of Lactobacillus fermentum CECT5716: A 3-year follow-up of a randomized controlled trial.

Lactobacillus fermentum CECT5716 is a probiotic strain originally isolated from human breast milk. Previous clinical studies in infants showed that the early administration of a milk formula containing this probiotic strain was safe and may be useful for the prevention of community-acquired infections. This is a 3-year follow-up study aimed at evaluating the long-term effects produced by the early consumption of an infant formula supplemented with L. fermentum CECT5716 (experimental group, EG) compared with a control formula without the probiotic (control group, CG). The infants included in this follow-up study had previously completed a 5-month randomized double-blind controlled trial (from 1 to 6 months of age), where the safety and tolerance of the probiotic formula was evaluated. The main outcome of the follow-up study was the growth of the children. The secondary outcomes included the incidence of infectious and non-infectious diseases, parameters related with intestinal function and faecal microbiota. At 3 years, the mean values of weight, length and head circumference were similar in children of the EG compared with those of the CG. No differences were observed in the incidence of infectious and non-infectious diseases or disorders related with intestinal function. The pattern of faecal microbiota was also similar between both groups. In conclusion, this 3-year study shows that the early administration of the probiotic of L. fermentum CECT5716 in an infant formula is safe and it does not produce measurable differences in children compared with a control formula.