Infant formula is an artificial substitute for human breast milk, designed for infant consumption. The first preparations for the feeding of infants were produced commercially in 1867 by Justus von Liebig. Today, most infant formulas are based on either cow milk or soy milk. Some formulas, for infants with special dietary needs, are highly modified and may contain neither cow milk nor soy. Use of infant formula has been decreasing in industrial countries for over forty years[citation needed] as a result of antenatal education, increased understanding of the risks of infant formula, and social activism.
A 2001 WHO report finds that infant formula prepared in accord with applicable Codex Alimentarius standards is a nutritionally adequate and safe complementary food and a suitable breast milk substitute. Nonetheless, with few exceptions the WHO report recommends exclusive breastfeeding for the first 6 months of life.[1]
Infant formula is necessarily an imperfect approximation of breast milk because:
The exact chemical properties of breast milk are still unknown.[2]
A mother's breast milk changes in response to the feeding habits of her baby and over time, thus adjusting to the infant's individual growth and development.[3]
Breast milk includes a mother's antibodies that help the baby avoid or fight off infections and give his immature immune system the benefit of his mother's immune system that has many years of experience with the germs common in their environment.