Clinical Outcomes of Prebiotic Intervention Trials during Infancy: A Review

The composition of the intestinal microbiota in breastfed infants is considered beneficial for the infant. Prebiotics have been used to mimic the effect of breastmilk on the intestinal microbiota. In the present review, the reported clinical outcomes in intervention studies during infancy are analyzed. For this review, original full articles were selected from theEmbase,SciSearch,Medline,PubMed, andCABdatabases. We included in the analysis randomized and quasirandomized, controlled trials that compared the use of a prebiotic to that of a nonprebiotic, or the use of a specific prebiotic compared to that of a different prebiotic, or the use of a specific prebiotic at different concentrations. Thirty-six studies have been reported following the inclusion criteria. Among them, 23 studies reported stool characteristics. Softer stools were consistently found with different prebiotic ingredients. This was accompanied with higher stool frequency and seen as prevention for common side effects of formula feeding. Twenty-two studies reported data concerning the immune system. The data allow the conclusion that specific prebiotics have the potential to reduce the risk of infectious episodes and the development of allergic symptoms. The existing data provide evidence that prebiotics can specifically modulate the composition of the intestinal microbiota, which potentially provides benefits for the infant. Positive effects have been demonstrated, particularly with respect to intestinal physiology and the immune system. The results of these clinical trials are supported by experimental data. Given that the effects of prebiotics on the intestinal microbiota may persist after finalizing the intervention, follow-up studies are crucial for final conclusions and for the purposes of clinical decision making.