Annales 74.3 - Human Milk: Lessons from Recent Research

Editor(s): F. Haschke. 74 / 3

Human milk is the best source of nutrients both for low-birth-weight (LBW) infants and healthy term infants. For LBW infants, the availability of human milk often is a problem, in particular during longer periods of hospitalization immediately after birth. Breastfed term infants in particular those in developing countries experience fewer and shorter infection periods. When compared to formula-fed infants, term infants fed human milk have different gut microflora, exhibit different growth patterns, and even face a lower long-term risk of chronic diseases, such as obesity, types 1 and 2 diabetes, and cardiovascular disease.

During recent years, it has become clear that human milk provides both optimal nutrient supply and functional ingredients, such as proteins, lipids, and oligosaccharides, which can contribute to short- and long-term health outcomes. Although the composition of infant formulas has evolved with increasing knowledge of human milk, differences in outcomes between breastfed and formula-fed infants are still observed. Efforts to improve the composition of infant formulas are complicated because human milk and its key components change continuously over time. Consequently, narrowing the gap between human milk and infant formula requires a deep understanding of how the quantity and quality of key nutrients change over time.


Human Milk Banking

Author(s): N. Haiden, E. E. Ziegler

Haiden and Ziegler review Human milk banks and how they  play an essential role by providing human milk to infants who would otherwise not be able to receive human milk. The largest group of recipients are premature infants who derive very substantial benefits from it. Milk banks collect, screen, store, process and distribute human milk .The largest group of recipients are premature infants who derive very substantial benefits from it. Milk banks collect, screen, store, process and distribute human milk.

Nutritive and Bioactive Proteins in Breast Milk

Author(s): F. Haschke

Protein ingested with breast milk provides indispensable amino acids which are necessary for new protein synthesis for growth and replacement of losses via urine, feces, and the skin. Protein gain in the body of an infant is highest during the first months when protein concentrations in breast milk are higher than during later stages of lactation. Low- birth-weight infants have higher protein needs than term infants and need protein supplements during feeding with breastmilk.
Based on our better understanding of protein evolution in breastmilk during the stages of lactation, new infant formulas with lower protein concentration but better protein quality have been created, successfully tested, and are now available in many countries. Besides providing indispensable amino acids, bioactive protein in breast milk can be broadly classified into 4 major functions, that is, providing protection from microbial insults and immune protection, aiding in digestive functions, gut development, and being carriers for other nutrients.
Individual proteins and their proposed bioactivities are summarized in this paper in brief. Indeed, some proteins like lactoferrin and sIgA have been extensively studied for their biological functions, whereas others may require more data in support to further validate their proposed functions.

Human Milk Lipids

Author(s): B. Koletzko

The lipid components of human milk provide the infant with energy and essential micronutrients, “and they also serve specific roles to support gastrointestinal function, lipid and lipoprotein metabolism, neurodevelopment, and immunity.
There have been significant advances both in food technology, which enables the supply of new lipid preparations, and in lipidomic analyses, which offer insight into the biological effects of complex lipids in infancy. These will pave the way for improvements in the feeding of infants who cannot be breastfed. 

Human Milk Oligosaccharides Influence Neonatal Muscosal and Systemic Immunity

Author(s): S. M. Donovan, S. S. Comstock

Donovan and Comstock review the role HMOs play in neonatal gastrointestinal and systemic immune development and function. Studies have shown that human milk contains a higher concentration, a greater structural diversity, and a higher degree of fucosylation than the milk oligosaccharides in other species, particularly bovine milk.

The commercial availability of large quantities of certain HMOs has allowed studying the functions of specific HMOs, which include protecting the infant from pathogenic infections, facilitating the establishment of the gut microbiota, promoting intestinal development, and stimulating immune maturation. Two HMOs, 2′-fucosyllactose (2′FL) and lacto-Nneotetraose (LNnT), have recently been added to infant formula.

The authors point out that this is an initial step to narrow the compositional gap between human milk and infant formula, but it is still not clear whether 1 or 2 HMOs will recapitulate the complexity of actions exerted by the complex mixture of HMOs in breast milk. Adding HMOs to formulas, however, is a big step forward compared to the addition of the first-generation ‘prebiotics’ to formula more than a decade ago.