Relationship between breast milk composition of full-term infants and children’s physical growth

Objective To study the characteristics of human milk composition at different time after delivery and their effects on growth of children.Methods The breast milk of 177 full-term Infants aged 0-6 months was collected. Determination of protein, fat,sugar, dry matter and energy in human milk by MIRIS HMA human milk analyzer. and it's the protein, fat, carbohydrate, dry matter and energy in the breast milk were measured by Miris HMA. The difference of breast milk composition in different time was analyzed,and the correlation between breast milk composition and infant growth was analyzed.Results The levels of total protein, true protein and nonprotein nitrogen(NPN) in breast milk showed a downward trend from 0 to 6 months, and the difference was statistically significantP<0.05). The physical data of infants were obtained when collecting breast milk(average 2.49 ±2.02 months old) and at early childhood(average 25.16 ±6.98 months old). The relationship between the infants' physical data and the composition of breast milk was analyzed. It was found that WAZ(breast milk collection time), LAZ(early infant) and the difference of growth index between early infant and breast milk collection time △WAZ、△LAZ were positively correlated with NPN, while the difference of body mass index(BMI) between early childhood and birth was negatively correlated with NPN(P<0.05).Conclusion The contents of total protein, true protein and NPN in breast milk decreased with the increase of infant age. NPN was beneficial to physical growth of infants, or it may be related to the preventive effect of breast milk on obesity of infant.