A recent report suggested that human milk (HM) composition not only changes with lactation stages but also vary according to gender of the offspring. In spite of available literature, the dynamic changes of HM composition still remain to be completely explored and characterized. Progress in analytical technologies together with quantitative sampling of HM allows for a better quantification of HM nutrients and thereby providing a deeper understanding of the dynamics of HM secretion.
To characterize and quantify HM nutrients based on appropriate for analyses sampling procedures and advanced analytical methodologies.
We conducted an observatory, single center, longitudinal trial with HM collection at 30, 60, and 120 days postpartum from 50 mothers (singleton-deliveries of 25 male and 25 female infants). HM samples were analyzed for lipid, lactose, energy density, fatty acids, phospholipids, and gangliosides. Longitudinal analyses of the datasets have been carried out using linear mixed models.
HM for male infants compared to females at 120 days, were higher for energy content and lipids by 24 and 39%, respectively. Similarly, other bioactive lipids such as linoleic acid, phospholipids and gangliosides were also significantly different based on the gender of the infant. Significant stage-based differences were observed for total lipids, energy density, phospholipids, and gangliosides. Such difference in HM composition may stem from different energy needs to cope up for individual growth and development.
Collectively, the current observations affirm that HM secretion, especially the lipid composition, is a very dynamic and personalized biological process. Am. J. Hum. Biol., 2013. © 2013 Wiley Periodicals, Inc.