The wonders of human breastmilk
Research findings on the extraordinary nature of human breastmilk are still
not commonly known. Although breastfeeding for the baby's first few weeks
is understood to be beneficial, both UNICEF and the World Health Organisation
now advise breastfeeding to two years and beyond. This is partly because
a child's immune system does not reach full strength until the age of five
years. According to Dr. Jack Newman, who has founded several breastfeeding
clinics in Canada, human breastmilk actively stimulates the infant's own
immune response. Breastfed babies, compared with bottlefed, have less diarrhoea,
urinary tract infections, pneumonia, vomiting, asthma, earaches, allergies,
cot death, various viral and bacterial infections, cancers, learning disabilities
and psychological problems. Milk's living cocktail of antibodies and cells
provide protection in a number of ways.
Sources for this are: Newman, J. How breast milk protects
newborns, Scientific American, 273(6), December 1995, 58-61,
and Russell, R.D., Design in infant nutrition, Impact No. 259, January
1995, ICR.
HELPFUL MOLECULES in milk include antibodies eg. immunoglobulin A, which is abundant in human breastmilk, perfectly compensates for the baby not producing this until several weeks after birth. These antibodies contain a secretory region to shield them from degradation by digestive enzymes. When the mother is exposed to pathogens in the immediate environment, within hours the next milk contains antibodies highly targeted against those pathogens. Thus the baby receives protection against the infections it is most likely to confront. Interestingly, these antibodies ignore `good'bacteria in the gut which crowd out pathogenic ones. Milk oligosaccharidesmimic the binding sites whereby bacteria gain entry into the cells lining the baby's gut (mucosal lining). Milk also contains lactoferrin, which binds to iron, thus inhibiting bacterial metabolism by rendering iron, which they much need, unavailable to them. Other milk molecules include Bifidus factor to promote growth of good bacteria, specifically Lactobacillus bifidus; Free fatty acids which damage the membranes surrounding enveloped viruses; and fibronectin to boost cellular defences and aid repair of inflammation-damaged tissues.
CELLULAR DEFENCES. White blood cells in milk have various functions. They engulf bacteria; produce the enzyme lysozyme, which disrupts bacterial cell walls; manufacture antibodies; mobilise other parts of the immune system; and produce chemicals (such as gamma interferon, monocyte inhibition factor) to stimulate the infant's own immune response. The infant's response matures more quickly (than in bottle fed babies) under the influence of other breastmilk factors such as cortisol, epidermal and nerve growth factor, insulin-like growth factor and somatomedin C. These close up the newborn's leaky mucosal lining, rendering it impermeable to pathogens. Other compounds stimulate the baby's own production of IgA, lactoferrin and lysozyme. These are found in the urine in larger amounts compared with bottle feeders, indicating that breastfeeding induces local immunity in the urinary tract.
FURTHER BENEFITS. The macronutrients in milk (carbohydrates, lipids and proteins) are perfectly balanced, and radically change in concentration according to the infant's stage of development. This even includes compensating for the special nutritional state of premature birth. Milk also contains vitamins and minerals, but also hundreds of other macronutrients, most of whose functions yet remain to be discovered. Some micronutrients enhance the bioavailability (ease of absorption) of other micronutrients. Earlier research concluded wrongly that human breastmilk was lacking in vitamin D, and so supplements were recommended. Then a form of vitamin D unique to breastmilk was discovered which totally meets the infant's needs.
Even today's formula milk falls far short of such optimum design. Also formula milk contains cow's milk proteins, which are preferably avoided in the first 6 months, after which ordinary cow's milk is an acceptable supplement, rendering expensive formula milk unnecessary. But formula milk is big business, mothers face advertising, cultural and work pressures. However, to provide immunity, 4 breastfeeds every 24 hours need not impede a reasonable working day, as is the current practice with my own 13 month old infant. What has brought me successfully through periods of difficulty (eg. very hungry baby) is the knowledge that God has designed the baby to feed at the breast. This brings the motivation, peace and assurance that breastfeeding is basically meant to work, and that man's substitutes are inferior to God's best. The recent findings on breastmilk's provision of immunity should reinforce our motivation.
Sheena Tyler (1996)
