Developing an Updated and Comprehensive Nutrient Profile for Human Milk Composition in the U.S. and Canada

Objectives: Human milk is recommended as the sole source of nutrition for infants up to about six months of age and recommended in combination with solid foods for at least the first year. The current nutrient profile for human milk shared by Canada and the United States (U.S.) has been moved to legacy status, meaning it can no longer be used to estimate current nutrient exposures. The objective of this study is to develop an interim human milk nutrient profile (iHMNut) that incorporates more recently published data on human milk composition in the U.S. and Canada to serve as a bridge until new analytical values can be established. Methods: Data from two literature reviews initiated by U.S. agencies of the Human Milk Composition Initiative (HMCI) and one large Canadian biomonitoring study were used to develop the iHMNut. Human milk collection and analytical methods were assessed against inclusion criteria of a review published by the National Academies of Sciences Engineering and Medicine (NASEM). Nutrient data from individual studies were extracted, quality control was performed, and weighted mean and standard deviation were calculated for each nutrient. These values were compared to the retired U.S. Department of Agriculture (USDA) Standard Reference (SR) Legacy profile for human milk. Results: A proposed iHMNut was generated for 22 nutrients, energy, and 22 fatty acids. Preliminary data analyses indicated that the largest percent differences in mean concentrations between USDA's SR Legacy profile and iHMNut were for thiamin (-87%), manganese (99%), and iron (-102%). The smallest percent differences were for phosphorus (-1%), calcium (1%) and lactose (2%). The mean concentrations of iodine and chloride, previously unreported in the SR, were calculated as 21.21 μg/100g and 43.72 mg/100g, respectively. Conclusions: These preliminary findings provide insight into the potential to develop an iHMNut profile estimating the nutritional composition of human milk to inform public health professionals and researchers. Furthermore, this process identifies nutrients with inadequate North American data, which may inform future research. The next step of this project will be subject matter expert review of these findings to gain additional insights to develop an iHMNut and move toward inclusion in the USDA Food Data Central Database. Funding Sources: N/A.