Although causality remains to be confirmed, current evidence supports the view that the gut microbiota play a role in human health and disease. If so, it is logical to assume that manipulation of the gut microbiota, such as through the administration of probiotics and/or prebiotics, could potentially be a preventive and/or therapeutic measure in the evolution of disease states. Here, some examples of current research related to probiotics are described. Certain probiotics prevent necrotising enterocolitis (NEC). Controversy exists whether current evidence is sufficient to change practice and start the routine use of probiotics in preterm infants to prevent NEC. Lactobacillus reuteri DSM 17938 is likely to reduce crying times in breast-fed infants with infantile colic. More studies, especially in formula-fed infants, are needed. Recently, for the first time, it was documented that L reuteri was effective for preventing infantile colic in both breast-fed and formula-fed infants. A number of RCTs found that probiotics (e.g. Lactobacillus GG and L reuteri DSM 17938) reduced the risk of gastrointestinal and/or respiratory tract infections. The use of probiotics with proven clinical efficacy (e.g. Lactobacillus GG, S. boulardii, L reuteri DSM 17938) is in line with current European recommendations for the management of acute gastroenteritis. There are studies that show a protective effect, no effect, or even a predisposing effect of using probiotics for preventing the allergic condition. For healthy infants, the administration of currently evaluated probiotic-supplemented formula to infants is safe with regards to growth and adverse effects.