Infant formulas on the market today should be aimed at providing the best alternative to breast milk for infants of those women who are unable to continue breastfeeding until 6 months of age and substituting ideally for human milk after 6 months of age approaching the structural and functional effects observed in breastfed infants. The aim is to mimic the functional outcome of the breastfed infant (e.g. growth and development), and not to copy the composition of human milk. For this purpose, the following compounds have been added to formulas and are reviewed: long-chain polyunsaturated fatty acids (LCPUFA) for brain composition and neurodevelopment, probiotics and prebiotics for the fecal flora and the local intestinal defense, and nucleotides for promoting the immune response. Changes in protein quantity and quality allow to balance the blood amino acid pattern (possibly relevant to the early stages of brain development for the neurotransmitter function) and reducing the protein intake could be important for the prevention of later overweight. Hydrolysed proteins are important in the prevention of atopic disorders. Many trials have been published so far with short-term assessments, most of them with positive findings. However, we need more data on the long-term follow-up of infants who were fed the new formulas. Such data will allow to look at neural performance, prevention of overweight and obesity, and effects on the immune-allergic pattern.