Human versus Cow's milk in infant nutrition and health: Update 1977

Abstract

The contents of human milk and of cows milk and their effects on infant nutrition and health are examined in this literature review in an effort to determine whether breastfeeding has any real benefits other than psychological benefits. Initial attention is directed to substances that are inherent to milk followed by extraneous materials such as drugs pesticides toxic minerals sensitizing foods and microorganisms that may be carried along in the milk and may have no effect or may be harmful to the infant. The high-fat high-lactose low-casein and low-ash composition of human milk makes it easily digestible by the infant. It also encourages the development of nonpathogenic flora in the intestine. Breastfed infants in developing countries have a significantly lower morbidity and mortality than bottle-fed infants. This is partly because of the characteristics of human milk and partly because of the presence of specific protective factors in the milk. These protecctive factors include antibodies against many bacterial and viral pathogens a fatty-acid anti-staphylococcal factor lysozyme the C3 component of complement lactoferrin a high molecular weight vitamin B12-binding protein a nonspecific antiviral substance and white blood cells. Overall morbidity and mortality rates in the developing countries are now similar for breastfed and bottle-fed infants yet several diseases are absent or less common in breastfed infants. Cows milk protein allergy expressed as diarrhea vomiting eczema rhinorrhea bronchitis and asthma is found only in formula-fed infants. The primary disadvantage of human milk to the infant is the chemical and biologic agents he or she may inbibe with it.