Association of maternal diet, micronutrient status, and milk volume with milk micronutrient concentrations in Indonesian mothers at 2 and 5 months postpartum.

BACKGROUND: Maternal micronutrient deficits during preconception and pregnancy may persist during lactation and compromise human milk composition. OBJECTIVE: We measured micronutrient concentrations in human milk and investigated their association with maternal micronutrient intakes, status, and milk volume. METHODS: Infant milk intake (measured via a deuterium dose-to-mother technique), milk micronutrient and fat concentrations, and maternal micronutrient intakes were assessed at 2 and 5 mo postpartum in 212 Indonesian lactating mother-infant pairs. Maternal hemoglobin, ferritin, transferrin receptors, retinol binding protein (RBP), zinc, selenium, and vitamin B-12 were measured at 5 mo (n = 163). Multivariate or mixed effects regression examined associations of milk micronutrient concentrations with maternal micronutrient intakes, status, and milk volume. RESULTS: Prevalence of anemia (15%), and iron (15% based on body iron), selenium (2.5%), and vitamin B-12 deficiency (0%) were low compared with deficiencies of zinc (60%) and vitamin A (34%). The prevalence of inadequate intakes was >50% for 7 micronutrients at 2 and 5 mo. Median milk concentrations for most micronutrients were below reference values, and nearly all declined between 2 and 5 mo postpartum and were not associated substantially with milk volume (except for ß-carotene, α-carotene, and ß-cryptoxanthin). At 5 mo postpartum, associations between maternal micronutrient status and corresponding milk concentrations reported as mean percentage difference in human milk concentration for each unit higher maternal biomarker were significant for hemoglobin (1.9%), iron biomarkers (ranging from 0.4 to 7%), RBP (35%), selenium (70%), and vitamin B-12 (0.1%), yet for maternal intakes only a positive association with ß-carotene existed. CONCLUSIONS: Most milk micronutrient concentrations declined during lactation, independent of changes in human milk production, and few were associated with maternal micronutrient intakes. The significant associations between maternal biomarkers and milk micronutrient concentrations at 5 mo warrant further study to investigate whether the declines in milk micronutrients are linked to shifts in maternal status.

Examination of Carbohydrate Products in Feces Reveals Potential Biomarkers Distinguishing Exclusive and Nonexclusive Breastfeeding Practices in Infants.

BACKGROUND: The stable isotope deuterium dose-to-mother (DTM) technique to estimate nonbreast milk water intake demonstrates that maternal self-report methods of infant feeding overestimate the true prevalence of exclusively breastfeeding practices. OBJECTIVE: We aimed to determine potential monosaccharide and oligosaccharide markers that distinguish between exclusively breastfed (EBF) versus nonexclusively breastfed (non-EBF) infants utilizing LC-MS-based methods. METHODS: Data for the analysis were collected as part of a larger, longitudinal study of 192 breastfed Indonesian infants aged 2 mo and followed up at 5 mo. Feces samples were collected from infants aged 2 mo (n = 188) and 5 mo (n = 184). EBF and non-EBF strata at each time point were determined via the DTM technique. Feces samples were analyzed to determine monosaccharide content using ultra-high-performance LC-triple quadrupole MS (UHPLC-QqQ MS). Relative abundances of fecal oligosaccharides were determined using nano-LC-Chip-quadrupole time-of-flight MS (nano-LC-Chip-Q-ToF MS). RESULTS: At age 2 mo, monosaccharide analysis showed the abundance of fructose and mannose were significantly higher (+377% and +388%, respectively) in non-EBF compared with EBF infants (P <0.0001). Fructose and mannose also showed good discrimination with areas under the curve (AUC) of 0.86 and 0.82, respectively. Oligosaccharide analysis showed that a 6-hexose (Hex6) isomer had good discrimination (AUC = 0.80) between EBF and non-EBF groups at 5 mo. CONCLUSION: Carbohydrate products, particularly fecal mono- and oligosaccharides, differed between EBF and non-EBF infants aged under 6 mo and can be used as potential biomarkers to distinguish EBF versus non-EBF feeding practices.