There remains much discussion about how best to feed a newborn baby; breast milk or formula. We all know the phrase 'breast is best', but it seems there is still a large population of mothers who, in the absence of a medical reason for not breast feeding, choose not to do so. This is despite the World Health Organization recommending that mothers exclusively feed their baby breast milk for the first 6 months of life.
What I wish to discuss here is one aspect of the science of why 'breast is best' and hope that it convinces the mothers who are choosing not to breastfeed, to do it, for the health of their baby.
Your baby is born with a gut and immune system that are functionally immature - that is, because they have been protected by you and the placenta during pregnancy, these organs haven't really had to do anything yet. All of the necessary parts are there, they just need some time to learn what to do.
When your baby is born, there are large gaps in between the cells within your baby's gut. This is so that large molecules from your body, including molecules produced by your immune system, can pass into your baby's blood. These molecules help to develop his/her immune system, as well as protect your baby until its own immune system is fully functional. After pregnancy, these very important molecules can only pass from your body to your baby via the breast milk. In fact, during the first days/weeks after birth, the cells within your breast also have large gaps in them so that these large molecules can pass out of your blood and into your breast milk for your baby. These important molecules are specific to you and your baby, and are not in formula feed.
The gaps in between the cells in your baby's gut are very important for the development of a healthy and strong immune system, but this also increases the risk of your baby getting an infection. Importantly, the gaps between the cells in the gut of babies that are fed breast milk close much more quickly than babies that are fed formula. Closure of the cell gaps in the gut minimize the risks of infection, so that your baby will be protected from getting infections much more quickly if you breast feed.
There is good scientific evidence that the health of your baby will be significantly improved by feeding him/her your breast milk, it is after all, what it is meant for, and what your baby's body is expecting.