Most infant formula is based on cow's milk that is extensively altered so that it closely mimics breast milk. The alteration process ensures that the formula has the right amount of carbohydrates and the right percentages of protein and fat. The Food and Drug Administration monitors the safety of commercially prepared formula. Manufacturers must test each batch of formula to make sure it has the required nutrients. Formula is also tested to guard against inadvertent contaminants, such as lead or pesticides.
Infants have very high energy requirements.
Infant formula, like breast milk, is designed to be an energy-rich food more than half its calories are from fat. Many different types of fatty acids make up fat, and those that go into infant formula are specifically selected because they are similar to those found in breast milk. These fatty acids help in the development of the brain and nervous system as well as in meeting your baby's general energy needs. The butterfat naturally found in cow's milk is replaced with certain vegetable oils to provide essential fats. Standard cow's milk formulas contain many vitamins, but most are relatively low in iron.