Whole cow’s milk contains about 87% water. The remaining 13% contains protein, fat, carbohydrates, vitamins, and minerals. Processing techniques remove fat to produce lower fat varieties: “reduced fat” contains 2% milkfat, “lowfat” contains 1% milkfat, and “nonfat” or “skim” has virtually no milkfat. Cows are often pregnant while they are milked, so dairy milk contains hormones like insulin-like growth factor-1 (IGF-1), estrogens, and progestins. Some cows are given additional hormones to increase milk production.