The first objective of infant formulas is to ensure the healthy growth of neonates and infants, as the sole complete food source during the first months of life when a child cannot be breastfed. Beyond this nutritional aspect, infant nutrition companies also try to mimic breast milk in its unique immuno-modulating properties. Numerous studies have demonstrated that the intestinal microbiota under the influence of diet shapes the maturation of the immune system and influences the risk of atopic diseases in infants. A new challenge for dairy industries is, therefore, to develop infant formulas inducing the maturation of immunity and the microbiota that can be observed in breastfed delivered vaginally, representing reference infants. Streptococcus thermophilus, Lactobacillus reuteri DSM 17938, Bifidobacterium breve (BC50), Bifidobacterium lactis Bb12, Lactobacillus fermentum (CECT5716), and Lactobacillus rhamnosus GG (LGG) are some of the probiotics added to infant formula, according to a literature review of the past 10 years. The most frequently used prebiotics in published clinical trials are fructo-oligosaccharides (FOSs), galacto-oligosaccharides (GOSs), and human milk oligosaccharides (HMOs). This review sums up the expected benefits and effects for infants of pre-, pro-, syn-, and postbiotics added to infant formula regarding the microbiota, immunity, and allergies.

Background: Food protein‐induced enterocolitis syndrome (FPIES) is a non‐IgE‐mediated food allergy, with potential dehydration secondary to vomiting. Differences exist regarding culprit foods, and age of tolerance depending on the country of origin. We aimed at describing the characteristics of a French population of children with FPIES, and define risk factors for failure during challenge.Methods: Data from 179 children who were referred for FPIES in two pediatric tertiary centers between 2014 and 2020 were retrospectively collected. The diagnosis of FPIES was based on international consensus guidelines. Clinical characteristics, culprit food, and age at resolution were assessed. Tolerance was defined as no adverse reaction after OFC or accidental exposure.Results: In the 192 described FPIES, the age at first symptoms was 5.8 months old. The main offending foods were cow's milk (60.3%), hen's egg (16.2%), and fish (11.7%). Single FPIES was observed in 94.4% and multiple FPIES in 5.6% of cases. The age at resolution of FPIES was 2.2 years old, and resolution occurred later for fish than for milk (2.9 years vs. 2.0, p = 0.01). Severe acute FPIES was a risk factor for delayed resolution (RR: 3.3 [1.2–9.2]), but not IgE sensitization. Performing a food challenge within 12 months after the first reaction increased the risk of failure (OR: 2.6 [1.1–6.6]).Conclusion: In this French cohort of children with FPIES, the main culprit foods were ubiquitous. Rice, oat, and soy were rarely or not involved. Multiple FPIES was infrequent. Our data confirmed the overall good prognosis of FPIES, the later resolution of FPIES to fish and in the case of severe acute FPIES.