|HAMPEL, DANIELA - University Of California
|DROR, DAPHNA - Consultant
|Allen, Lindsay - A
Submitted to: Advances in Nutrition
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/28/2017
Publication Date: 5/29/2018
Citation: Hampel, D., Dror, D., Allen, L.H. 2018. Micronutrients in human milk: analytical methods. Advances in Nutrition. 9:313S-331S. https://doi.org/10.1093/advances/nmy017.
Interpretive Summary: The purpose of this article is to evaluate the methods that have been used for analysis of micronutrients in human milk. The point is made that many analytical methods used for analysis of blood, plasma or urine need modification when applied to analysis of nutrients in the human milk matrix. However, this fact has often been ignored with failure to validate or evaluate the methods used. We summarize current knowledge about methods used for analyzing water- and fat-soluble vitamins as well as minerals, the different forms of these nutrients in milk, tools that can be used for quality control and assurance, and guidance on the need to control for pre-analytical factors. The article ends with a summary of preferred analytical methods.
Technical Abstract: Exclusive breastfeeding is recommended by the World Health Organization (WHO) for the first six months of life as human milk protects against gastrointestinal infections and provides balanced and adequate nutrient levels to the infant. However, reliable data on micronutrient concentrations in human milk is sparse especially as some micronutrients are affected by maternal diet. Microbiological and competitive protein binding assays, nuclear magnetic resonance (NMR) or inductively coupled plasma (IPC) spectroscopy, and chromatographic analyses are among the methods that have been applied to human milk micronutrient analysis. However, the validation or evaluation of analytical methods in terms of their suitability for the complex human milk matrix have been commonly ignored in reports even though the human milk matrix differs vastly from blood, plasma, or urine matrices. Thus, information on the validity, accuracy, and sensitivity of the methods is essential for the estimation of infant requirements and maternal intake requirements to support and maintain adequate milk micronutrient concentrations for healthy infant growth and development. In this review we summarize current knowledge on methods used for analyzing water- and fat-soluble vitamins as well as iron, copper, zinc, iodine, and selenium in human milk and their different forms in milk, the tools available for quality control and assurance, and guidance for pre-analytical considerations. Finally we recommend preferred methodological approaches for analysis of specific milk micronutrients.