For nine long months, you nurtured your baby within the secure confines of your womb. Your little one was protected by your immune system and nourished by the food you ate.
After birth and out of the safety of your womb, your newborn’s various systems – including the immune system – need to function on their own. In the first few days of life, your little one’s immune system is not fully developed yet and needs time to strengthen. Some of this development is linked with your baby’s gut flora, or the microorganisms that live in your child’s digestive system.
Baby gut flora: How gut health builds baby’s immunity
We may think that all microorganisms are bad for our health. However, some bacteria, viruses and fungi are crucial for good health – and most of these inhabit the human gut, including your newborn’s. The gut is the gastrointestinal system that includes the stomach, small intestine and colon.
At just a few weeks old, your newborn’s gut is home to a community of millions of bacteria, viruses and fungi – or gut flora. Most are helpful to the body (symbiotic), others could be potentially harmful (pathogenic). This community of microorganisms (also known as the microbiome) coexist in a healthy body without causing health issues. In fact, gut flora have an essential role in health – they stimulate the immune system and regulate the immune homeostasis.
The immune system plays a vital role in defending against harmful microorganisms while working with beneficial bacteria to keep the body healthy. A disruption to the balance of good and bad bacteria (for example, through a poor diet, or prolonged use of antibiotics) may have a negative impact on health.1 In other words, your newborn’s immunity can be boosted by maintaining a healthy gut.
The role of birth in establishing your baby’s microbiome
Given that the womb is sealed off and sterile in nature, you might be wondering how your newborn’s gut gets populated by these microorganisms. A large part of the answer lies in the mode of delivery. Birth is when your baby is exposed to microorganisms that then colonise your newborn’s gut. There is a difference between the kind of gut bacteria that migrate to your baby’s system during a natural delivery and a Caesarean section.
A large study2 revealed that babies born naturally receive much of their gut flora from their mother, while more bacteria that are typically found in a hospital setting inhabited the guts of babies delivered through Caesarean sections. These “hospital bacteria” are also known as “opportunistic pathogens” and are often present in healthy babies without causing an issue. However, if immunity is low or these pathogens get into the bloodstream, then health issues may occur. Mums who have undergone a Caesarean section shouldn’t worry too much though, as this difference in baby gut flora disappears when the baby is weaned.
The early years are critical: How to nurture your little one’s gut health
The first step in nurturing your baby’s gut health can start as early as pregnancy. Even though we know that babies receive much of their gut flora during birth, research3 suggests that bacteria inhabit a baby’s gut even before birth. Ensuring that the expecting mother’s diet is rich in foods that support her own microbiome – like fruits, vegetables, nuts, yoghurt and legumes – could help lay the foundation for her baby’s good gut health after birth.
Having a pet is also another surprising way of boosting your baby’s microbiome, especially if your little one was born via Caesarean section. A study5 involving over 750 infants showed that owning a pet was linked with an increase of two types of beneficial gut microbes – Ruminococcus and Oscillospira – which are associated with lower odds of developing allergies and obesity.
Other benefits of a healthy gut
In addition to contributing to a strong immune system, a healthy microbiome can help eliminate food toxins6 and also form important nutrients like vitamin B12. Beneficial microorganisms also assist in the digestion of complex carbohydrates.7 There is also a strong link between a healthy gut microbiome and the prevention and reduction of the severity of allergies, including food allergies as well as eczema.8, 9
Even as you nurture your little one’s gut health, don’t forget to look after your own. You can do this by10:
- Eating foods high in prebiotics like vegetables, lentils and beans. These are the food source of probiotics that help “grow” good bacteria in the gut. Examples of foods that contain probiotics include kimchi, kombucha, miso, sauerkraut, and tempeh.11
- Taking the time to relax and unwind as there is a relationship between gut health and your mental health.
1 DeWeerdt, S. How baby’s first microbes could be crucial to future health. Nature. Published on 7th March, 2018. Accessed on 21st February, 2022 fromhttps://www.nature.com/articles/d41586-018-02480-6
2Hunt, K. Babies born by C-section have less of their mom’s gut bacteria. Here’s why that might be important. CNN Health. Published on 19th September, 2019. Accessed on 22nd February, 2022 from https://edition.cnn.com/2019/09/18/health/babies-gut-microbiome-birth-vaginal-c-section-intl/index.html
3 Walker, R. et al. The prenatal gut microbiome: Are we colonized with bacteria in utero? Pediatric Obesity. Published on 26th April, 2017. Accessed on 22nd February, 2022 from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5583026/
4The Royal Children’s Hospital Melbourne. Probiotics for Infants and Children (Factsheet). Accessed on 22nd February, 2022 from https://www.rch.org.au/uploadedfiles/main/content/ccch/cpr_vol22_no1_factsheet.pdf
5Tun, H. et al. Exposure to household furry pets influences the gut microbiota of infants at 3–4 months following various birth scenarios. Microbiome. Published on 6th April, 2017. Accessed on 22nd April, 2022 fromhttps://microbiomejournal.biomedcentral.com/articles/10.1186/s40168-017-0254-x
6Sandrine P Claus, et al. The gut microbiota: a major player in the toxicity of environmental pollutants? NPJ Biofilms Microbiomes. Published on 4th May 2016. Accessed on 25th May 2022 from ncbi.nlm.nih.gov/pmc/articles/PMC5515271/
7Harvard T.H. Chan School of Public Health. The Microbiome. Accessed on 22nd April, 2022 from https://www.hsph.harvard.edu/nutritionsource/microbiome/
8Scientific American. Gut Microbes May Be Key to Solving Food Allergies. Published on 20th May, 2020. Accessed on 22nd February, 2022 from https://www.scientificamerican.com/article/gut-microbes-may-be-key-to-solving-food-allergies/#:~:text=Studies%20have%20further%20solidified%20the,different%20communities%20of%20gut%20bacteria.
9Eczema Foundation. The gut microbiome and eczema: How are probiotics beneficial? Accessed on 22nd February 2022 from https://www.fondationeczema.org/en/support/useful-advices/microbiome-and-eczema
10 VicHealth. How to improve your gut health. Accessed on 22nd February, 2022 from https://www.vichealth.vic.gov.au/be-healthy/how-to-improve-your-gut-health
11MedicalNewsToday. Probiotic foods: What to know. Accessed on 25th May 2022 from https://www.medicalnewstoday.com/articles/323314