Milk. It does no body good.
Stage of lactation – Content source
Human lactation stage can be divided into 3 major phases: colostrum, transitional milk, and mature milk. Colostrum is rich in immunologic components and contains relatively low concentrations of lactose but higher protein content, suggesting its important functions to be immunologic and trophic besides nutritional.
Transitional milk shares some of the characteristics of colostrum but represents a period of accelerated milk production to support the infant’s nutritional and developmental needs for rapid growth.
Mature milk is relatively similar to transitional milk, but the changes are not as remarkable as in the early weeks. The influence of lactation stage differs for different nutrients. For example, total protein and lipids show a gradual decrease during the first 6 mo of lactation. Whereas the lactose is initially low in colostrum and transitional milk, it then increases in mature milk and remains at the same levels for up to 6 mo. In addition to the alterations of total protein, protein composition also changes. Milks mainly contain 2 types of protein: caseins and whey proteins. The ratio of whey to casein in human milk can vary from ∼80:20 in early lactation to ∼50:50 in late lactation. Because the amino acid compositions differ between caseins and whey proteins, the type and content of the amino acids of human milk in turn vary during lactation.