Infant Gut Microbiota & Immunity: Groundbreaking research on C-section born infants 

Title: Infant Gut Microbiota & Immunity: Groundbreaking research on C-section born infants 

Did you know that the gut microbiota plays an important role in immune health? Around 70-80% of the body’s immune cells are found in the gut, making it a central player in immune function and development. ¹Belkaid Y et al. Immunity, 2017;46(4):562–76. , ²West CE et al. J Allergy Clin Immunol, 2015;135(1):3–13 , ³Vighi G et al. Clin Exp Immunol, 2008;153(SUPPL. 1):3–6 The first 1000 days of life are particularly important for shaping the gut microbiota and establishing a strong immune system. ⁴Walker WA et al. Pediatr Res, 2015;77(1):220–8.

Breastmilk provides essential nutrients such as human milk oligosaccharides, bacteria, and metabolites that support the gut microbiota and immune system development in this time window. ⁵Pereira PC. Nutrition, 2014;30(6),619–27 , ⁶Agostoni C et al. J Pediatr Gastroenterol Nutr, 2009:49:112–25. , ⁷Zivkovic AM et al. Proc Natl Acad Sci USA, 2011 (15);108 Suppl 1:4653–8. However, early gut microbial colonization can be influenced by various factors, including the mode of birth and feeding.⁸McDonnell L, Gut Microbes, 2021; Vol.13, No. 1, e1870402., ⁹Kumar H et al. Microorganisms, 2020;8(12).

Infants born via cesarian-section (C-section) may experience delayed colonization of bacteria, such as beneficial bifidobacterium species, which can lead to increased infection rates and a greater reliance on antibiotics compared to vaginally born infants. ¹⁰Miller JE et al. PLoS medicine. 2020 :17,e1003429 , ¹¹Shao Y et al. Nature. 2019:574(7776):117-121, ¹²Shaterian N et al. Open Med. 2021;16-624-639

At Danone Research & Innovation, our scientists have conducted extensive research to explore how specialized nutrition strategies such as a unique synbiotic containing infant formula —combining prebiotics (scGOS/lcFOS) and probiotic (bifidobacterium breve M-16V)— can help restore gut microbial colonization as typically observed in vaginally delivered infants.

Their research has found:

• RCT1 (2017): In this study involving 153 C-section born infants, supplementation with this specific synbiotic (scGOS/lcFOS and B.breve M-16V) formula helped restore bifidobacterium levels, bringing them closer to those observed in vaginally born babies. Based on the adverse effects, there is an indication for a significant reduction in skin symptoms with the unique synbiotic supplementation.¹³Chua MC et al. JPGN. 2017:65(1):102-106
• RCT2 (2025): The randomised clinical trial reinforced the findings of the previous study, i.e. highlighting the benefits of this specific synbiotic supplementation on C-section born infants during the early months of life. Additionally, the synbiotic-containing formula increased the relative abundance of other early-life bacterial species in C-section born infants.¹⁴Wang Y et al. Eur J Clin Nutr.2025. doi:10.1038/s41430-025-01571-8
• Observational study in Hong Kong (2025): This real-world evidence study confirmed that the specific synbiotic (scGOS/lcFOS and B.breve M-16V) supplementation supports the findings of gut microbiota restoration findings observed in the clinical studies. Additionally, this unique synbiotic supplementation may reduce illness episodes in C-section born infants, as parent-reported illnesses were significantly reduced at 12-month follow-up.

These studies demonstrate the link between gut microbiota and immunity. Supplementing C-section born infants with a unique synbiotic (scGOS/lcFOS and B.breve M-16V) containing formula helps restore bifidobacterium levels to those typically found in vaginally born infants, potentially supporting better immune development during the first 1000 days. ¹⁵Chua MC et al. JPGN. 2017:65(1):102-106 , ¹⁶Wang Y et al. Eur J Clin Nutr.2025. doi:10.1038/s41430-025-01571-8