Breast milk sodium concentration, sodium intake and weight loss in breast-feeding newborn infants

Abstract

Elevated breast milk (BM) Na concentration is regarded as responsible for elevated Na intake. To verify the clinical significance of milk Na concentration, we studied the relationship between BM Na þ concentration and infants' daily Na þ intake, infants' daily BM intake (DBMI) and percentage weight loss (%WL) in healthy newborn infants. All mothers who gave birth to a single healthy infant, between February and March 2004 at the Obstetric Clinic of University of Messina (Italy), were invited to participate if they were willing to attempt to breastfeed exclusively. BM Na þ concentration, DBMI, Na þ intake and %WL were determined on the third day after delivery. Statistical analysis was performed by Spearman's correlation test, classification and regression trees and the generalised linear model. Of the 270 eligible mothers, 208 participated in the study. The results showed that on the third day postpartum BM Na þ concentration was 23·05 (SD 1·10) mmol/l, mean DBMI was 202 (SD 68·9) g/d, and mean Na þ intake was 4·36 (SD 0·22) mmol/d and 1·36 (SD 0·07) mmol/kg per d. BM Na þ concentration was inversely related to infant DBMI, and Na þ intake was directly related to infant DBMI and not to BM Na þ concentration. %WL was significantly correlated only to DBMI. In conclusion, the present data demonstrate, for the first time, that when lactogenesis is suboptimal, BM Na þ concentration is higher, but infants' Na þ intake is lower. Finally, the present data probably suggest that for the clinical assessment of breast-feeding, evaluation of milk intake remains the best method.Breast milk sodium: Infant sodium intake: Infant weight loss

Subclinical mastitis occurs frequently in association with dramatic changes in inflammatory/anti-inflammatory breast milk components

“…The exact consequence of SCM on infant development remains to be established. A relationship between severe mammary inflammation during SCM and poor weight gain or lower breast milk intake has been reported [43] 14 one breast in human, making possible for the unaffected breast to increase the milk output to maintain milk intake. Authors have suggested that the raise of sodium and inflammation in breast milk may be associated with reluctance to accept milk from the affected breast during SCM [17].…”

“…Antileukoproteinase 1 is secreted during experimental mastitis in animals [42]. α-defensins are microbicidal peptides produced notably by weight gain or lower breast milk intake has been reported [43] [17] [44]. SCM occurs frequently in one breast in human, making possible for the unaffected breast to increase the milk output to maintain milk intake.…”

Infant and Maternal Factors Influencing Breastmilk Sodium Among Primiparous Mothers

“…7,18,24 No single measure could confirm that LS-II was initiated, 22 although cutoffs in the range of 3-18 mmol/L have been proposed after Day 3.…”

Subclinical Mastitis May Not Reduce Breastmilk Intake During Established Lactation

“…Manganaro et al 29 CMT ϭ 0 (n ϭ 37) or Ն1 (n ϭ 23). The 25 th and 75 th percentiles are demarcated by the box, the median is represented by the dark horizontal line, and the whiskers represent 1.5 multiplied by the interquartile range.…”