By IANS,
Washington : Girls being breastfed are better protected than boys against respiratory infections, a finding that challenges the existing belief that mother’s milk equally protects all babies against disease.
Following the progress of 119 premature babies in Buenos Aires through their first year, researchers found that breast-feeding offered more protection to girls than boys.
Besides newborn, formula-fed girls were eight times more likely than breast-fed girls to develop serious respiratory infections requiring hospitalisation, the study results showed.
Formula-fed girls were also more likely to develop such infections than both breast-fed and non-breast-fed boys.
The findings, researchers say, are particularly important for healthcare in developing countries, where antibiotics and other treatments are scarce and where an estimated one-fourth of premature babies end up in the hospital with severe respiratory infections.
The findings questioned the theory that immune system chemicals contained in breast milk and passed directly from mother to the newborn are responsible for preventing the infections.
If this were the case, researchers say, both boys and girls would likely derive equal protection.
In addition, breast-feeding did not appear to affect the number of infections, but rather their severity and the need for hospitalisation.
It implies that breast milk does not prevent a baby from getting an infection, but helps a baby cope with an infection better.
“In light of these results, we are starting to think that milk does not directly transfer protection against lung infections but instead switches on a universal protective mechanism, already in the baby, that is for some reason easier to turn on in girls than in boys,” said senior investigator Fernando Polack, a specialist at Hopkins Children’s.
If breast milk does indeed trigger a universal — but variably activated — protective mechanism against multiple viruses, the next step is to figure out exactly how this mechanism gets switched on and why it is relatively harder to activate in boys.
The findings have been reported in the June issue of Paediatrics.