Nutritional quality of breast milk
Breast milk is nature's recipe for the ideal food for infants. It provides all the nutrition necessary for infants to double their weight by about 6 months of age. The American Academy of Pediatrics recommends breast milk (or an appropriate baby formula) in all infants up to 1 year of age and as long as it is beneficial to mother and infant after 1 year of age.
What is colostrum?
Colostrum is the milk produced a mother immediately after the birth of her infant. Approximately 7 to 123 milliliters of colostrum is produced in the first 24 hours after the child's birth. The infant drinks about 7 to 14 milliliters (a quarter to a half of a teaspoon) at each early feeding. This milk is gradually replaced during the first week of the infant's life. Mother's milk production is stimulated by the newborn's suckling and typically has a normal white "milk-like" appearance after about 4 days.
Colostrum often has a clear orange-tinged appearance. Compared with mature breast milk, colostrum has more protein and minerals and less carbohydrates and fats.
How many calories does breast milk have?
On average, breast milk has 20 kilocalories (kcal) per ounce. You may notice that this is the same concentration of calories found in commercial milk formulas. A healthy newborn requires about 100-120 kilocalories per kilogram of body weight at birth. While the total amount of calories required increases with age, the calories per kilogram of body weight decreases.
How much breast milk does an infant drink?
Beginning by about day 5 of life, an infant typically drinks about half of a liter of breast milk per day (about 17 fluid ounces). By about 6 months of age, an infant drinks between half of a liter to a little over one liter of breast milk per day. Baby's are able to "regulate" the amount of breast milk production based on their individual needs. The more vigorously and frequently a baby feeds, the more the mother's milk glands will be stimulated... therefore more milk is produced.
Breast milk, under normal circumstances, provides the necessary amount of water for an infant.
How much does human breast milk vary from mother to mother?
Amazingly, human breast milk varies very little from mother to mother. The mother's diet, age, country of origin, and race have little affect on the composition of breast milk.
How much fat is in breast milk?
Human breast milk contains between 30 and 50 grams per liter of fat. This provides about half of the calories in breast milk. When an infant is born premature, mother's breast milk contains a higher amount of calorie-dense fats. Breast milk contains all the necessary types of fats (including the essential fatty acids). The amount of fat in the mother's diet does not affect the amount of fat in the breast milk, however the composition of the fats may be different. The concentration of fat is greater in the milk released later during a single breastfeeding. This is why it is important for an infant to spend more than a short time at each breast during a feeding.
How much carbohydrate is in breast milk?
Lactose accounts for most of the carbohydrate in human milk. The concentration of lactose in mature breast milk is about 70 grams per liter and may be affected by the mother's diet. Lactose is broken down into galactose and glucose which provide a rapid energy supply to a growing infant. Lactose intolerance is extremely rare in newborns and infants, but becomes a common problem in older children and adults.
How much protein is in breast milk?
Human breast milk contains about 9 grams of protein per liter and remains at a stable concentration. The 2 major types of proteins in breastmilk are casein and whey and these 2 components vary in proportion as the infant ages. Breast milk protein is about 90% whey in the first breastfeedings and about 60% in mature breast milk. Cow milk contains mostly casein proteins which is not as easily digested by young infants.
How about vitamins in breast milk?
Breast milk contains a "multivitamin" in every feeding. Vitamin deficiency in a breastfeeding infant is rare. Perhaps the most important possible vitamin deficiency in these infants is vitamin D. There have been scattered reports of vitamin D deficiency (and subsequent rickets) in infants who only receive breast milk. This has led the American Academy of Pediatrics to recommend vitamin D supplements in all strictly-breastfed infants. While this type of rickets is rare, it is more common in infants with dark skin who are not exposed to much sunlight; other substances in the skin can be converted to vitamin D by sunlight.