Wednesday, July 31, 2013

Breastfeeding Promotes Beneficial Gut Bacteria in Infants

After reading the article Gut Microbes for Life by Ed Young that discussed the relative long term stability of our gut flora I wondered if the way a mother chooses to feed her baby had any effect on the bacterial make-up of an infant’s gut and if that had any effect on long term health related to gastrointestinal diseases. All major medical associations recommend exclusive breastfeeding for 6 months followed by continued breastfeeding with the addition of age appropriate foods until at least 1 year of age. The health benefits of breastfeeding to both mom and baby have been researched extensively and are now accepted by much of the general population. Healthy People 2020 goals are to have 81.9% of moms initiate breastfeeding, 46.2% exclusively breastfeeding at 3 months, 60.6% breastfeeding at 6 months, 25.5% exclusive breastfeeding at 6 months, and 34.1% breastfeeding at 1 year.  Even with the research highlighting the benefits of breastfeeding many mothers choose to formula feed their infants. The CDC 2012 Breastfeeding Report card shows only 76.9% of mothers initiating breastfeeding, 36% exclusive at 3 months, 47.3% breastfeeding at 6 months, 16.3% exclusive breastfeeding at 6 months, and only 25.2% at 1 year.

The intestinal flora is important for the development of the immune system and normal intestinal structure and function. There appears to be many different ways in which breastmilk promotes the development of healthy gut flora while protecting infants against both short-term and long-term intestinal issues.  Breastfeeding promotes a higher number of Bifidobacteria. Bifidobacteria inhibits the growth of harmful bacteria and pathogens. The gut of a breastfed baby has a lower pH which promotes the growth of Bifidobacteria and also inhibits the growth of harmful bacteria. Formula fed infants have more harmful bacteria such as coliforms, enterococci and bacteroides. As formula fed infants age, they also will get more Bifidobacteria but the breastfed infants level remain many times higher.

Another way that breastfeeding helps promote gut health is through the development of biofilms that form a barrier against pathogens and infections. This is especially important for infants since the junctions of the gut mucosa are pretty open and allow pathogens to pass through easily. This is further augmented by sIgA that the mother produces and passes on through the breastmilk. These antibodies are specific to pathogens in the infant environment that have the potential to cause disease. This sIgA coats the gut and provides another layer of protection.
Breastmilk also contains human milk oligosaccharides, complex carbohydrates that are not in formula. These oligosaccharides help to promote healthy gut bacteria that initially protect the infant from infections. As the infant gets older, the oligosaccharides change and produce different fatty acids that help the immune system develop that provides protection against food allergies and asthma.
Research is just beginning to look at how the difference in bacteria, pH, biofilms and immunologic development from breastfeeding is affecting different intestinal disease. One study looked specifically at infants who had a high-risk for the development of Celiac Disease. Breastfeeding was shown to decrease the bacteria that were associated with the development of Celiac Disease. Breastfeeding increased the prevalence of B. uniformis bacteria that was more often seen in the low-risk group. A meta-analysis of research showed that breastfeeding was associated with a decreased risk of both Crohn's Disease and Ulcerative Colitis.            


Just one bottle won’t hurt—or will it? Marsha Walker, RN, IBCLC  


  1. Wow, I knew that breastfeeding was a better way to feed a baby but I never really knew why or the statistics behind it. After reading about all the statistics I feel like many new mothers and soon to be mothers are not fully informed about the benefits of breastfeeding their infants. It is very interesting how it makes an impact in the child later into their life based on the bacteria, pH, biofilms and immunologic development in the breast milk.

  2. I agree totally. I have always heard from my mom that breastfeeding is the best thing for the baby, but I didn't know exactly why. I think I have also heard somewhere about the benefits of having a natural birth versus a Cesarian c-section. If I remember correctly, the process of being born naturally gives the baby beneficial bacteria, but babies who were not born naturally had lower levels of these bacteria. It's pretty amazing how our bodies work to keep us, and our babies healthy.

  3. I like this post. I am pro breastfeeding. I was thinking about the discussion we had on how people in the same family have very similar bacteria in their gut. I would imagine this would amplify that effect. Along with providing a closer connection with baby and the benefits of immunities passed, this is just another great reason to attempt to breast feed. I do realize it is just not possible for some women to breast feed for many reasons, I'm not judging anyone that doesn't. I just think it's great when a woman does.