A cross-sectional study of macronutrients, vitamins, minerals, and bioactive components in human milk of approved milk bank donors from low-, middle-, and high-income countries

Authors: PERRIN, MARYANNE - University Of North Carolina; MANSEN, KIMBERLY - Path; ISRAEL-BALLARD, KIERSTEN - Path; BODE, LARS - University Of California, San Diego; HAMPEL, DANIELA - University Of California, Davis; Shahab-Ferdows, Setareh; Allen, Lindsay; MAGGIO, FRANCISCA - Hospital Dr Sotero Del Rio; NJUGUNA, EMILY - Path; TRAN, HOANG - University Of Da Nang; WESOLOWSKA, ALEKSANDRA - Medical University Of Warsaw

Submitted to: The American Journal of Clinical Nutrition
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/29/2025
Publication Date: 9/18/2025
Citation: Perrin, M.T., Mansen, K., Israel-Ballard, K., Bode, L., Hampel, D., Shahab-Ferdows, S., Allen, L.H., Maggio, F., Njuguna, E., Tran, H.T., Wesolowska, A. 2025. A cross-sectional study of macronutrients, vitamins, minerals, and bioactive components in human milk of approved milk bank donors from low-, middle-, and high-income countries. The American Journal of Clinical Nutrition. https://doi.org/10.1016/j.ajcnut.2025.07.031.
DOI: https://doi.org/10.1016/j.ajcnut.2025.07.031

Interpretive Summary: Human milk is not only providing all the nutrients needed for healthy infant growth and development, but also protects against illness such as necrotizing enterocolitis. Thus, if the own mother's milk is not available, donor human milk (DHM) is recommended for at risk newborns. However, clinical care is curbed due to the lack of information on the nutritional and bioactive composition of DHM. Therefore, we evaluated DHM from approved milk banks in different low-, middle-, and high-income countries, and compared their macro- and micronutrien, human milk oligosaccharide, and antimicrobial protein composition. Further, we investigated factors that affect the composition, such as gestational stage (preterm versus term), lactation stage, maternal age, and lifetime donation volume. This cross-sectional study systematically collected samples from milk bank donors (n=600) in Chile, Kenya, Poland, the United States, and Vietnam. We analyzed protein, total fat, lactose, human milk oligosaccharides, vitamins, minerals, and antimicrobial proteins. We found that most nutrients differed significantly across the different countries, which was related to the stage of lacttaion during collection (colostrum/transitional milk vs mature milk). E.g., protein and many minerals were higher in the early milk while lactose and several water-soluble vitamins were higher in the mature milk samples. Other nutrients showed differences not related to lactation stage, including B12, riboflavin, and choline. Included other factors which are commonly known to the milk banks, such as lactation stage, birth term, maternal age and lifetime donation volume, in our models, most of the variation (>60%) remained unexplained. In summary, considering the local milk donor banking model may be beneficial to clinical protocols for feeding DHM to preterm infants. Pooling milk from multiple donors should be further examined as an option for milk banks to safeguard a minimum nutrient standards for DHM.

Technical Abstract: Background. Donor human milk (DHM) is recommended for small vulnerable newborns in the absence of their mother’s milk due to its protection against necrotizing enterocolitis. Currently, clinical care is limited by a dearth of information on the nutritional and bioactive composition of DHM. Objective. Primary: assess and compare the macronutrients, vitamins, minerals, human milk oligosaccharides, and antimicrobial proteins in human milk from approved milk banks in a variety of low-, middle-, and high-income settings. Secondary: explore factors that influence composition including gestational stage (preterm versus term), lactation stage, maternal age, and lifetime donation volume. Methods. We conducted a cross-sectional study of human milk collected systematically from unique, approved milk bank donors (n=600) in Chile, Kenya, Poland, the United States, and Vietnam. True protein, total fat, lactose, human milk oligosaccharides, vitamins, minerals, and antimicrobial proteins were assessed. Results. Most nutrients differed significantly between geographies which was primarily associated with whether the milk bank collected donations predominantly from the early lactation period (1-2 weeks postpartum) or from the mature lactation period. True protein and many minerals were higher in the early donation model while lactose and several water-soluble vitamins were higher in the mature donation model. Setting-specific differences not related to donation model were noted for some nutrients including B12, riboflavin, and choline. When considering factors typically known to milk banks including lactation stage, birth term, maternal age and lifetime donation volume, most variation (>60%) remained unexplained. Conclusion: Clinical protocols for feeding DHM to preterm infants, including setting-specific fortifier products, may need to take into consideration the local donor milk banking model. Multi-donor pooling warrants further investigation as a tool for milk banks to ensure minimum nutrient standards for DHM.