Milk mineral and trace element concentrations from Mam-Mayan mothers were measured and used to assess breastfed infantâs daily intake of minerals and trace elements and their association with infant WAZ, LAZ and HCAZ at 3 stages of lactation.
In a cross-sectional study, transitional (5-17d, n=56), early (18-46d, n=75) and established (4-6mo, n=103) milk samples were collected. Infant anthropometry measurements (WAZ, LAZ, HCAZ) were recorded. Concentrations of 11 minerals (Ca, K, Mg, Na, Cu, Fe, Mn, Rb, Se, Sr, Zn) were analyzed by ICP-MS. The amount of milk needed in meeting infantsâ energy demands were calculated and daily mineral and trace element intakes were derived accordingly.
K, Na, Cu, Fe, Mn, Se and Zn were lower, whereas Mg was higher during established compared to transitional and early lactation. Milk intake during established lactation was insufficient to compensate for the lower Na, Cu, Mn and Zn concentrations in milk among male and Na, Fe and Mn concentrations among female infants. During transitional and early lactation, very few infants had adequate intakes of Ca, K, Mg, and Se, but none of the infants met the daily AI for Na. Principal component regression analyses showed that Ca, Mg, K, Rb and Sr intakes clustered together in early lactation and were associated with better anthropometric outcomes. In established lactation, the same minerals plus Na were positively associated with all 3 anthropometric Z-scores.
Breast milk mineral and trace element intakes are associated with infant growth in the first 6 months of life in Guatemala.