Nutritional and Non-nutritional Composition of Human Milk Is Modulated by Maternal, Infant, and Methodological Factors

Abstract

Human milk (HM) is dynamic and shows a high inter- and intra-individual variability. To characterize HM with precision, it is necessary to understand the factors that modulate its composition. The objective of this narrative review is to summarize the maternal, infant and methodological factors that affect HM composition. We searched SCOPUS and PubMed databases for articles related to factors that are known to or could potentially influence HM composition and volume across lactation periods. Our comprehensive review encompasses various maternal-, infant-related, and methodological factors that modulate aspects of HM composition including macro- and micronutrients, vitamins and minerals, as well as volume. The most profound changes were observed in HM lipids and lipophiles. Evidence exists for many of the infant-related factors known to affect the nutritive and non-nutritive components of HM (e.g., birth weight, gestational age, infant age/stage of lactation). In contrast, less is known with respect to maternal factors; where there is either limited research or conflicting evidence (e.g., maternal lifestyle, obstetric history, medical conditions), except for the mother's diet, for which there is a relatively well-established understanding. Equally, although many of the methodological factors (e.g., HM sampling, handling and analytics) are known to impact HM composition, few studies have investigated this as a primary outcome, making it an important area of future research in HM. Here we propose a systematic capture of numerous maternal- and infant-related characteristics to facilitate associative comparisons of HM data within and across studies. Additionally, it would be prudent to standardize the methodological aspects known to affect HM composition in analytics, not only for HM lipids and lipophiles, but also for those nutrients whose variability is yet less well-understood. Defining the factors determining HM composition with accuracy will open perspectives for maternal intervention to optimize milk composition for specific needs of infants.

Survey of effect of protein supplementation on body growth indices and immune system development in premature neonates with very low birth weight

“…One of the supplementary proteins that is effective in improving weight gain and head circumference growth, height and probably the immune system (4). The American Academy of Pediatrics (AAP) and the WHO strongly recommend breastfeeding for preterm and premature infants, but it doesn't meet newborns protein requirements (3); so it is necessary to enrich breast milk to meet the needs of the VLBW infants. A common strategy for enriching breast milk is the addition of fortified milk supplement (FMS) (5)(6)(7).…”

“…©Copyright 2021 by Erciyes University Faculty of Medicine -Available online at: www.erciyesmedj.comThis study was performed with the assumption that high-dose supplementary proteins improve weight gain in preterm infants compared to moderate doses or absence of the supplementary protein. Miller et al showed that the group receiving protein (4.2 gr/kg/d) showed a higher weight gain compared to the group receiving the protein (3.6 gr/kg/d)(3). Also, the results of Rochow & Biasin's study showed similar effects of high-dose protein supplement in increasing the weight gain(6,7).…”

Exposure to per- and polyfluoroalkyl substances associates with altered lipid profile of breast milk

“…The chemical composition of human milk changes from colostrum to late lactation, and varies within feeds, diurnally, and between mothers ( 1 ), being influenced by both maternal and environmental factors and showing high inter- and intra-individual variability ( 3 ). It has been shown that birth weight, gestational age, infant age/stage of lactation has an impact on the composition, but less is known how the maternal factors such as lifestyle (except for the mother’s diet) and socio-demographic factors are affecting the BM composition.…”

“…It has been shown that birth weight, gestational age, infant age/stage of lactation has an impact on the composition, but less is known how the maternal factors such as lifestyle (except for the mother’s diet) and socio-demographic factors are affecting the BM composition. Interestingly, the socioeconomic status and geographical location were found to have an impact particularly on the lipid composition of the milk ( 3 ). For example, a more favourable balance between omega-3 and omega-6 polyunsaturated fatty acids (PUFAs) was observed in BM of Swedish women compared with Chinese women ( 4 ).…”

Human Milk Drives the Intimate Interplay Between Gut Immunity and Adipose Tissue for Healthy Growth

“…lactation and between mothers (6,7). The link between the nutrients and other bioactives in human milk and growth occurs at various levels, from appetite regulation to direct sensing of nutrients by immune cells in the intestine.…”