How Does Breastfeeding Shape Baby’s Immune System & Gut Health

Dr. Jolene BrightenPublished: Last Reviewed: Pregnancy Leave a Comment

The intricacies of the human body are vast. It’s only recently that we’re beginning to understand the true makeup of our microbiome and what these tens of trillions of microorganisms are capable of. This blog is going to examine the connections between breastfeeding, baby immune system health, and gut health.

Gut bacteria helps to shape and strengthen our immune systems over time and we’ve already found links between gut bacteria and mood disorders like depression and ADD.

Your Unique Microbiome

There are about 1,000 known species out of those trillions with more than 3 million genes. While much of the microbiome is common to most people, a majority of it is specific to each individual, much like a unique fingerprint.

We’re still learning a great deal about how this happens, but diet, environment, genetics, and microbial exposure are all part of the discussion. We do know that our unique microbiome makeup begins forming before we ever enter this world.

Breastmilk Establishes Good Gut Health

We already know that human breast milk contains an array of compounds with anti-infectious properties. We also know that, in general, babies who are breastfed go on to have fewer infections than those babies who were bottle-fed.

And while mothers have intuited since the beginning of time that breast milk is imperative for baby’s health, we’ve only recently scientifically identified breast milk as a source of commensal and potential probiotic bacteria, making for healthy baby immune systems.

Breastfeeding Prevents Gut Infections

Breast milk contains a vast array of protective molecules, including the antibody IgA. We eventually make this antibody for ourselves, but in those early days, our mother’s milk is the only source.

Without IgA antibodies, gut bacteria proliferates differently and these babies tend to suffer from more gut infections, including Irritable Bowel Disease (IBD) and intestinal permeability.

IgA is instrumental in keeping bacteria in check. Even after we begin to make our own IgA, those who haven’t been breastfed are more prone to inflammation and infection.

One study shows that viable gut bacteria may be transferred from mother to baby via breastfeeding. And have shown that maternal gut bacteria reach the breast milk via an entero-mammary pathway to influence baby’s microbiome makeup and help build the baby immune system.

Breastmilk Contains Prebiotics

Other studies show that human milk oligosaccharides (HMO) in mother’s milk act as prebiotics in baby. Prebiotics feed the good gut bacteria and promote bacterial diversity.

Prebiotics, like those found in breastmilk, encourage a diverse and happy gut bacteria population that promotes robust health and reduces the incidence of infection.

Breastfeeding is a Personal Relationship Between You and Your Baby

As always, touting the benefits of breastfeeding is in no way meant to shame mother’s who cannot breastfeed for any reason.

But given the information coming out about the negative impact of C-sections on baby’s microbiome, I wanted to share with you how breastfeeding can have a positive impact on baby’s gut despite how the baby is born.

As a mother, your gut health and breastfeeding are one of the greatest influences on baby's immune system and overall health.

In my clinic, we focus on establishing incredible gut health prior to becoming pregnant and support breastfeeding mothers in maintaining their health so that they can continue to provide the care their infant needs.

Looking for more breastfeeding support?

In my book, Healing Your Body Naturally After Childbirth: The New Mom’s Guide to Navigating the Fourth Trimester, I share a wealth of ideas, recipes, and tips for the new mom – all rooted in the science-driven, time-tested, holistic approach of Naturopathic Medicine.

Healing Your Body Naturally After Childbirth | Baby immune system

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About The Author

Dr. Jolene Brighten

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Dr. Jolene Brighten, NMD, is a women’s hormone expert and prominent leader in women’s medicine. As a licensed naturopathic physician who is board certified in naturopathic endocrinology, she takes an integrative approach in her clinical practice. A fierce patient advocate and completely dedicated to uncovering the root cause of hormonal imbalances, Dr. Brighten empowers women worldwide to take control of their health and their hormones. She is the best selling author of Beyond the Pill and Healing Your Body Naturally After Childbirth. Dr. Brighten is an international speaker, clinical educator, medical advisor within the tech community, and considered a leading authority on women’s health. She is a member of the MindBodyGreen Collective and a faculty member for the American Academy of Anti Aging Medicine. Her work has been featured in the New York Post, Forbes, Cosmopolitan, Huffington Post, Bustle, The Guardian, Sports Illustrated, Elle, and ABC News. Read more about me here.