Total Protein, Secretory Immunoglobulin A and Lactoferrin Concentrations in the Breastmilk of Lactating Women and their Correlation with Nutritional Intake

Background and objectives: Mothers’ breastmilk is the best source of nutrition for infants; hence, its nutritional adequacy is essential. The purpose of this study is to evaluate the total protein, secretory immunoglobulin A (sIgA) and lactoferrin (LF) concentrations of breastmilk from lactating mothers in Jakarta and analyse their correlation with average daily calory, macronutrient and vitamin C and E intakes. Methods and study design: A cross-sectional study was conducted in two primary health centres in Jakarta, Indonesia. The breastmilk’s total protein concentration was measured with the Warburg–Christian method, while sIgA and LF concentrations were measured by enzyme-linked immunosorbent assay (ELISA). Macronutrient and vitamin C and E intake was assessed through 24-hour food recall and a semi-quantitative food frequency questionnaire (FFQ), respectively.Results: Thirty-six lactating women were recruited. The mean plasma protein was 8.17 g/dl, breastmilk protein was 3.36 g/dL, sIgA was 4.37 g/L and LF was 14.36 g/L. The total energy, carbohydrate, protein, fat and vitamin C and E daily intakes were 1828.61 kcal/day, 234.76, 71.15, 72.31 gram/day, 109.7 mg/day and 5.60 mg/day, respectively. Neither plasma and breastmilk total protein nor sIgA and LF concentrations were correlated with total energy, macronutrients or vitamin C and E daily intake.Conclusions: The plasma total protein, breastmilk total protein, sIgA and LF concentrations of lactating women in Jakarta were within the normal range. These biochemical profiles were shown to be not significantly correlated with daily calory, macronutrient or vitamin C or E intake.Keywords: breastmilk protein; secretory immunoglobulin A; lactoferrin; macronutrients; vitamins