Biochemical Differences in Human Breast Milk Contents According to Infant's Gender

Human milk composition is dynamic, and varies between mothers in the same and different populations. Breast milk content was also found to vary diurnally, over a feeding and in some species according to the gender of the breast feeding infant. This study aimed to determine if there are any quantitative differences in the biochemical constituents of breast milk according to the gender of the breast feeding infant. Forty eight breast feeding mothers participated in the study, 24 were breast feeding male infants and 24 were breast feeding female infants. Five ml of breast milk was collected from each mother then analyzed for lipid contents, carbohydrates, proteins and calcium. Carbohydrates, amino acids and calcium concentration were measured using colorimetric test of absorbance. There were significant differences in the concentration of lipids and calcium in breast milk of male and female breast feeding mothers (P-value<0.001 and 0.02, respectively). Our study indicates that breast milk is more dynamic than previously thought and concentration of breast milk contents should not be taken as fixed. This can lead to developing personalized formula feeding specific to the baby’s gender and age and matches his/her growth needs.