Infant formulas on the market today represent the only available alternative to breast milk for infants of those women who are unable to continue breastfeeding through the first year of life, and are planned to allow artificially fed infants for approaching the structural and functional effects observed in breastfed infants. Within this context, the functional outcome of the breastfed infant (particularly as far as growth and development) well represent the gold standard. For this purpose, the following compounds have been added to starting infant formulas (planned for the first six months of life, when human milk should represent the exclusive dietary source) in recent years: 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 acids 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 may be relevant in the prevention of atopic disorders. Many trials have been published so far with short-term assessment, nevertheless, we need more data on the long-term follow-up of infants who were fed the new formulas to fully understand the role of these functional compounds on the neural performance, the prevention of overweight and obesity and the development of the immune-allergic pattern.