Selected Human Milk Oligosaccharides Added to Infant Formulas for Term Infants

The benefits of breastfeeding, such as reduced risk of gastrointestinal and respiratory tract infections, depend largely on the presence of bioactive compounds in breast milk, including human milk oligosaccharides (HMOs). The presence of HMOs represents one of the largest differences in composition between breast milk and infant formula. Currently, progress in biotechnology allows the production of selected HMOs such as 2'-fucosyllactose (2'-FL) and lacto-N-neotetraose (LNnT), which are increasingly being added to infant formulas to narrow the difference between breast milk and formula. It is important to differentiate HMOs naturally occurring in human breast milk from those biotechnologically produced, which, while identical to HMOs in breast milk, do not originate from breast milk. This chapter summarizes basic facts about HMOs, findings from observational studies assessing the relationship between specific HMOs and clinical effects, and evidence from randomized controlled trials with structures identical to HMOs in breast milk added to infant formulas. Overall, the findings from some recently published trials provide reassurance that infant formulas supplemented with selected structures identical to HMOs, specifically 2'-FL with/out LNnT, are safe and well tolerated, and may have favorable effects on some health outcomes and medication usage. Further studies are needed.