For most babies, exclusive breastfeeding for six months is recommended to ensure optimum nutrition and minimize risk of infection. Specific commercial formula is appropriate if the infant has a genetic disorder related to processing galactose or certain amino acids. In cases where the mother may be infected with HIV, TB, or otherwise in ill health, or be on a number of medications or illicit drugs, health providers may recommend human donor breast milk. When these alternatives are not available, formula is a necessary alternative.
Mechanism of Action
Most infant formulas are designed to approximate the contents of human breast milk. Purified cow’s milk whey and milk derivatives provide protein; vegetable oils typically provide fat; lactose and corn syrup provide carbohydrates; and each manufacturer adds vitamins and minerals. The American FDA requires the inclusion of linoleic acid, niacin, folic acid, pantothenic acid, calcium, magnesium, iron, zinc, manganese, copper, phosphorus, iodine, sodium chloride, potassium chloride and vitamins A, C, D, E, K, B1, B2, B6, and B12. Formulas designed specifically for premature infants are more calorically dense and have higher protein, vitamin and mineral levels per serving than traditional formulas.
Despite the complexity of formula and the conditions it can address, breastfeeding continues to be the best strategy in most low-resource conditions. Mothers milk has antibodies which are not in formula. Furthermore, formula is non-sterile and is constituted with a water source which also may be a vector for infections.
Current Use in High-Resource Settings
For premature infants born after less than 34 weeks gestation, oral feeding may not be possible, and formula is often given through a fine feeding catheter passed through the mouth to the stomach. More mature infants can feed from a bottle. Many high-resource settings have breast milk donation programs, reducing the medical need for formula. Formula is used to increase calories and supplement babies who are not growing.
Application in Low-Resource Settings
The uses for formula in low-resource settings are twofold: for mothers who cannot or will not breastfeed, and as a nutritional/caloric supplement for preterm, small for gestational age, or other selected infants. The use of formula has been a controversial issue. In response to instances of overuse, an international code to regulate the marketing of formula was adopted 1981. It specifies that formula packaging must state the benefits of breast milk and that formula cannot be promoted or given free to mothers or caregivers. Powder-based formulas, which must be mixed with water, can pose risks in areas where clean water is not readily available. Formula feeding may also be difficult for social reasons, as it can be associated with HIV stigma.