14 DAY TRIAL // The old idea that all breastfed children are equally protected against diseases has been recently blown away by a study showing that girls benefit more than boys from the protective effects of the breast milk, but also that girls fed with baby formula are more likely to fall victim to a respiratory infection that their siblings of opposite sex.
The study was carried out by the Johns Hopkins Children's Center and involved the monitoring of 119 prematurely born babies in the city of Buenos Aires, throughout the first year of their lives. If indeed the breast milk helped boost the immune system of the babies then girls and boys should equally share the protection of the chemicals in the milk.
Furthermore, the number of diseases doesn't appear to be affected in any way by breastfeeding, although it does have a significant impact on the severity of the disease. "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", says infectious disease specialist Fernando Polack from Johns Hopkins Children's Center, who was also the leader of the study.
On the other hand, baby girls who are not breastfed are up to eight times more likely to develop a respiratory infection than those benefiting from the protection of the breast milk. The same is available in comparison with all baby boys, whether the have been fed baby formula or not. The results of the study are extremely important for developing countries, since reports show that a quarter of all prematurely born babies end up developing a severe respiratory infection.
"When resources are limited, it helps to know that your high-risk group is formula-fed girls", Polack says.
Even in countries with the antibiotic means to stop the development of complications, breastfeeding is still regarded as the best way to provide babies with the required nutrients regardless of gender, helping the development of the brain and health in general. According to the study, 6 percent of all prematurely born breastfed girls had a severe respiratory infection after birth, as opposed to the 50 percent of baby formula fed girls. The percentage of boys is of 18 percent, regardless of the method of nutrition.
The next step in the study would be to find out why breast milk protects the babies preferentially according to gender. "Unraveling this mechanism may one day lead to broad-based therapies that might be as effective as five or six vaccines", Polack said.