Breast Milk Output and Composition

Volume and Energy Content

The average breast milk output for a fully breastfed infant is approximately 780-800 mL per day, with this volume remaining relatively stable during the first 6 months of exclusive breastfeeding, according to the American Academy of Nutrition and Dietetics 1
Breast milk contains 60-70 kcal/100 mL, with fat providing the majority of calories, as recommended by the American College of Nutrition 1, 2
At average production of 780 mL/day with 0.67 kcal/g energy density, lactation requires approximately 670 kcal/day energy expenditure, as estimated by the National Academy of Sciences 3

Mixed feeding (breast milk + formula): 341-497 g/day, and breast milk + formula + complementary foods: 90-508 g/day, as reported by the Academy of Nutrition and Dietetics 1