Your New Baby's Immune System: What You Need to Know

The Value of Breast Milk

Breast milk not only has unquestionable nutritional value, but it provides infants with an added level of immune protection that no commercial formula has been able to duplicate. That’s because even colostrum—the first milk produced by new mothers—contains large numbers of antibodies and other infection-fighting cells. Through breast milk, nursing mothers are able to provide their babies with a continued source of antibodies long after they deliver. As a result, breastfed babies are protected against many if not all of the diseases to which their mothers’ are immune. It is because of this significant boost in immunity that breastfed babies have been shown to get sick less often, suffer from fewer ear infections, and experience less severe symptoms when they do get sick. And while you may be familiar with the risk of uneven heating and scald burns associated with microwaving breast milk, it’s worth noting that doing so is also thought to destroy the immune properties of the milk.

The Fear of Fever

Having a baby with a stuffy nose can be very challenging, since it more often than not means that he’ll eat and sleep poorly and be fussy, but there are even more important reasons to avoid exposing your baby to even the common cold. Keeping very young infants from catching colds and getting fevers is more than a matter of convenience. Because of their immature immune systems, young infants are less able to fight infections than older children and adults. While babies have the same likelihood as we do of having a routine and relatively harmless viral infection, their potential for getting a serious and potentially overwhelming bacterial infection is much greater. While fevers often go along with the former, they also serve as warning signs for the latter. This is why fevers are taken much more seriously in the first few months of life, and why they almost always necessitate a trip to the doctor’s office at best, and quite often, the real possibility of blood and urine tests, a spinal tap, or even a hospital admission and IV antibiotics.

Using Caution and Common Sense

Understanding what you now know about an infant’s immune system and the benefits that a mother’s antibodies confer, you might wonder why it is that we still use such caution around even breastfed newborns. After all, we know that they are relatively well-protected by their mother’s antibodies for weeks after birth, even when they’re not breastfed, and for the months or years after that if they are. The reason is most likely one of common sense.

While we know that young infants aren’t entirely defenseless, there are many effective and practical ways for you to keep your baby healthy in addition to breastfeeding. As mentioned at the start of this article, they involve simple measures such as good hand washing, avoiding people who are most likely to be sick (which not only includes those who have fevers, snotty noses or hacking coughs, but also children—a group who is known to spend a great deal of time contagious with one form of common cold or another). Anything you can reasonably do that helps to limit the demands placed on your baby’s immune system in the early months will help keep her healthy and you both happy.