Changes in Mature Human Milk Macronutrient Composition over 45 years in an Urban Population in Indonesia.

Background: With improvement in a population's welfare, its food consumption patterns may change, including those of nursing mothers. This, in turn, could influence their human milk composition.

Research Aim: To investigate the secular trend in macronutrient composition of mature human milk from mothers of healthy, full-term infants in urban populations in Indonesia from 1974 and 2019.

Method: We compared the macronutrient composition of mature human milk of healthy full-term infants from 1974 and 2019. The data from 2019 used the Human Milk Analyzer MIRIS to quantify the milk's carbohydrate, fat, and protein content, while the historical data used methods available at that time, that is, methods described by Benedict, Gerber and Kjeldahl, respectively.

Results: There were no significant differences in carbohydrate, protein and fat content across categories of maternal nutritional status in the respective periods. However, the fat content of human milk from 2019 was significantly higher than that of 1974 (4.7 g/dl,  = 1.7 g/dl vs. 3.3 g/dl,  = 1.1 g/dl;  < 0.001), while its carbohydrate content was significantly lower (6.2 g/dl,  = 2.1 g/dl vs. 7.1 g/dl,  = 0.2 g/dl;  < 0.001). There was no difference in the protein content between the two periods (1.4 g/dl,  = 0.5 g/dl vs. 1.6 g/dl,  = 0.3 g/dl;  = 0.491).

Conclusion: The mature human milk from 2019 has a higher fat and total energy content but lower carbohydrate content than those observed 4 decades ago. The protein content remained the same.