Infants who do not receive adequate amounts of breast milk are particularly susceptible to infections by intestinal pathogens. The milk of humans and domestic animals carries protective factors such as immunoglobulins and oligosaccharides that provide a significant amount of protection to the recipient. It has been proposed that the diet of infants at risk of intestinal infections could be supplemented with protective factors found in cows ‘ milk or eggs, particularly immunoglobulins. The evidence in support of supplementation of infant formula is reviewed, as well as some of the work in progress.