Reference Values for B Vitamins in Human Milk: The Mothers, Infants and Lactation Quality (MILQ) Study

This third article in the series presenting reference values (RVs) for nutrients in human milk describes the values for B vitamins. The mothers, infants, and lactation quality (MILQ) and early-MILQ studies, conducted at sites in Bangladesh, Brazil, Denmark, and The Gambia, were designed to measure human milk nutrient concentrations of well-nourished mothers during the first 8.5 mo of lactation. Applying ultrahigh-performance liquid chromatography-mass spectrometry (UPLC-MS/MS) to analyze multiple B vitamins simultaneously produced RVs for vitamin B2, B3, pantothenic acid, B6, and biotin. Choline was analyzed separately by UPLC-MS/MS, vitamin B1 by high-performance liquid chromatography-fluorescence detection, and vitamin B12 by competitive chemiluminescence enzyme immunoassay. Measured milk B-vitamin concentrations from the MILQ study were compared with those used by the Institute of Medicine (IOM) for setting recommendations for nutrient requirements of infants. MILQ estimates were substantially lower (<60% of the concentrations used by the IOM) for vitamins B1, B2, and B6; 60%-100% of concentrations used by the IOM for vitamin B3, vitamin B12, and choline; and consistent or slightly (100%-125%) higher than concentrations used by the IOM for pantothenic acid and biotin. Total daily median B-vitamin intakes from 1 to 6 mo were 29%-45% of IOM adequate intakes (AIs) for vitamins B1 and B2, 60%-75% of AIs for vitamins B3, B6, B12, and choline, and 118%-128% of AIs for pantothenic acid and biotin. The MILQ B-vitamin concentrations are provided as percentile curves to enable comparison and interpretation of data from other studies.