Breastfeeding provides “human milk for human babies” for optimal brain development, immune system protection, and digestive compatibility. Research shows that breastfed babies have slightly higher intelligence quotients (IQs) than babies fed infant formula. They have fewer infections and the onset of allergies is delayed. Breastfed babies may have a reduced risk of obesity and chronic diseases, such as diabetes. Mothers who breastfeed may have a decreased risk of breast and ovarian cancers, and possibly a decreased risk of osteoporosis and hip fractures. Although any amount of breastfeeding is beneficial, exclusive breastfeeding for the first 6 months is associated with greater health benefits.

Despite the many benefits of breastfeeding, there are incidences and conditions in which breastfeeding is contraindicated. For example, galactosemia is a hereditary disease that is caused by the lack of a liver enzyme required to digest galactose. Galactose is a breakdown product of lactose, which is most commonly found in milk products. Because galactose cannot be broken down, it accumulates in the cells and becomes toxic. The body then produces abnormal chemicals, which causes the symptoms seen in infants with untreated galactosemia.

Galactosemia usually causes no symptoms at birth, but jaundice, diarrhea, and vomiting soon develop and the baby fails to gain weight. If not detected immediately, it results in liver disease, cataracts, mental retardation, and possibly death. Death can occur as early as 1 to 2 weeks of age from severe Escherichia coli bacteria infections. E. coli infections are common in untreated galactosemic infants. The American Liver Foundation recommends that all infants who develop jaundice be considered for galactosemia.

Other contradictions to breastfeeding include: