The mothers, infants and lactation quality (MILQ) study: introduction and study design

Authors: Allen, Lindsay; MOORE, SOPHIE - King'S College; KAC, GILBERTO - Universidade Federal Do Rio De Janeiro; MICHAELSEN, KIM - University Of Copenhagen; MOLGAARD, CHRISTIAN - University Of Copenhagen; ISLAM, M. MUNIRUL - Icddr,b; Shahab-Ferdows, Setareh; CHRISTENSEN, SOPHIE - University Of Copenhagen; LEWIS, JACK - University Of Copenhagen; PEERSON, JANET - Consultant; TAN, XIUPING - University Of California, Davis; Dror, Daphna; Doel, Andrew; ANDERSSON, MARIA - University Hospital Zurich; DE BARROS MUCCI, DANIELA - Universidade Federal Do Rio De Janeiro; FIGUEIREDO, AMANDA - Universidade Federal Do Rio De Janeiro; SCHNEIDER, BRUNA - Universidade Federal Do Rio De Janeiro; KHANAM, FARHANA - Icddr,b; DE SOUZA CAMPOS, ADRIANA - Universidade Federal Do Rio De Janeiro; TORRES SILVA, GABRIELA - Universidade Federal Do Rio De Janeiro; NIJE, FANTA - London School Of Hygiene & Tropical Medicine; HASSAN, MEHEDI - Icddr,b; KURPAD, ANURA - St John'S Research Institute: Sjri; DEVI, SARITA - St John'S Research Institute: Sjri; JONES, KERRY - University Of Cambridge; HAMPEL, DANIELA - University Of California, Davis

Submitted to: Advances in Nutrition
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/15/2025
Publication Date: N/A
Citation: N/A

Interpretive Summary: The World Health Organization (WHO) recommends exclusive breastfeeding (EBF) of infants up to six months of age and continued breastfeeding up to two years or beyond. However, there is limited reliable, representative data on nutrient concentrations in milk from well-nourished mothers who have not taken vitamin-mineral supplements, which could increase levels in milk, and on the volume of milk transferred to infants during stages of lactation. Accurate quantification of both nutrient concentrations and milk volume is essential for setting Reference Values (RVs) and recommended levels of intake for macronutrients (protein, fat, and lactose), and vitamins and minerals (micronutrients) for infants, and women’s additional requirements for lactation. This first paper in a series of seven in this Supplement describes the Mothers, Infants, and Lactation Quality (MILQ) and Early-MILQ (E-MILQ) studies, designed to develop RVs nd measure milk volume during the first 8.5 months of lactation in well-nourished mother-infant dyads at sites in Bangladesh, Brazil, Denmark, and The Gambia. Validated analytical methods were used to measure the amounts of nutrients and milk volume. A total of 932 mother-infant dyads participated in the MILQ study (1-8.5 mo lactation) and 313 in the E-MILQ study (0-1 mo lactation). Milk volumes, milk nutrient concentrations, RV percentile curves and total nutrient intakes (concentration multiplied by milk volume at each time point) are presented in the series of articles in this supplement. Comparisons are made between values in the MILQ study and those used by the Institute of Medicine to set nutrient intake recommendations for infants and lactating women, and to other selected studies. RVs from the MILQ and E-MILQ studies provide a valuable resource for updating existing nutrient intake recommendations, evaluating and improving infant nutrition strategies and assessing interventions aimed at optimizing maternal and infant nutritional status and health.

Technical Abstract: The World Health Organization (WHO) recommends exclusive breastfeeding (EBF) for the first six months of life and continued breastfeeding up to two years or beyond. However, limited reliable, representative data are available on nutrient concentrations in milk from well-nourished, unsupplemented mothers. Furthermore, there is a paucity of data on the volume of milk transferred to infants during progressive stages of lactation. Accurate quantification of both nutrient concentrations and milk volume is essential for setting Reference Values (RVs) and recommended levels of intake for macro- and micronutrients for infants, and women’s additional requirements for lactation. This first paper in a series of seven in this Supplement describes the Mothers, Infants, and Lactation Quality (MILQ) and Early-MILQ (E-MILQ) studies, conducted in well-nourished mother-infant dyads at sites in Bangladesh, Brazil, Denmark, and The Gambia, to measure human milk nutrient concentrations and milk volume throughout the first 8.5 months of lactation. Validated analytical methodologies were used for nutrient quantification. The gold-standard stable isotope dilution dose-to-mother method was used for milk volume measurement. A total of 932 mother-infant dyads participated in the MILQ study (1-8.5 mo lactation) and 313 in the E-MILQ study (0-1 mo lactation). Milk volumes, milk nutrient concentrations, RV percentile curves and total nutrient intakes (concentration multiplied by milk volume at each time point) are presented in the series of articles in this supplement. Comparisons are made between values in the MILQ study and those used by the Institute of Medicine to set nutrient intake recommendations for infants and lactating women, as well as to other selected studies. RVs from the MILQ studies provide a valuable resource for updating existing nutrient intake recommendations, evaluating and improving infant nutrition strategies and assessing interventions aimed at optimizing maternal and infant nutritional status and health.