(P07-052-23) Human Milk Nutrient Composition Data Is Critically Lacking in the United States and Canada: Results From a Systematic Scoping Review of 2017–2022

Objectives: Characterization of the nutrients and bioactive components in human milk is important to understand the dietary and developmental requirements of infants. The objective of this review was to summarize the state-of-the-science on the nutrient composition of human milk in the United States and Canada published from 2017 to 2022.

Methods: Four databases (MEDLINE, CINAHL, ProQuest, and Web of Science) were searched for randomized controlled studies and others (e.g., prospective cohort studies) on the scoping nature of this review. We limited the type to mature milk collected 21 days postpartum and beyond from lactating individuals in the United States and Canada who gave birth at 37 weeks’ gestation or later (full-term). Outcomes of interest included traditional nutrients (e.g., macronutrients, amino acids, fatty acids, vitamins, minerals), human milk oligosaccharides (HMOs), as well as milk volume. The publication date range was selected as January 1, 2017, to the day the literature search was performed.

Results: A total of 32 articles were included in the scoping review from primarily longitudinal cohort or cross-sectional designs. The most prevalent sample collection method was full breast expression (n=20) with most studies obtaining samples from a single timepoint (n=26). Carbohydrates (HMOs [n=12], glucose [n=8], and lactose [n=6]) and protein (n=5) were the most frequently assessed nutrients in this body of work. Included studies displayed an overall level of heterogeneity and sparsity paralleling previous reports and nutrient data in the USDA FoodData Central system. Most studies provided single or limited nutrient analyses that was unable to account for the full complexity of mature milk. Moreover, many studies did not use the preferred analytical methods as outlined by the Human Milk Composition Initiative to increase measurement accuracy.

Conclusions: Up-to-date nutrient composition data of human milk is still greatly needed as it is paramount for the management of infant feeding, assessing infant and maternal nutritional and health needs, and as a reference for infant formula development.

Funding Sources: NIH/NICHD