Not only is breastfeeding better for the baby, however, research also says it’s better for the mother. Breastfeeding burns an average of 500 calories a day, with the typical range from 200 to 600 calories burned a day. It’s estimated that the production of 1 oz. of breast milk burns 20 calories. The amount of calories burned depending on how much the baby eats. Breastfeeding twins burn twice as much as feeding only one baby. With twins their mom burns 1000 calories a day. Burning an extra 500 calories a day will result in one pound of weekly weight loss. Studies have shown that breastfeeding mothers lose more weight after pregnancy than bottle-feeding moms.