Syneo and gut health

It is becoming increasingly clear that the gut plays a central role in our overall health; specifically, the complex system of micro-organisms that live within the gut, collectively known as the gut microbiota.

Gut microbiota: a key role in the immune system

The gut microbiota is made up of more than 35,000 species of bacteria, plus millions of other microorganisms such as viruses, fungi, archaea, and protozoa1.  This highly diverse community exists, for the most part, in harmony with their host, and can influence the way their body works1.


A healthy, balanced gut microbiota helps the immune system defend against pathogens, whilst tolerating otherwise harmless substances2,3,  such as pollen and milk protein (leading to no or few severe allergic reactions). Conversely, an imbalanced gut microbiota – also called gut microbiota ‘dysbiosis’ – is linked to allergies and diseases such as asthma, inflammatory bowel disorders, eczema and diabetes4,5.

There is now a growing body of evidence that suggests that gut microbiota dysbiosis in early life is closely linked to the development of food allergies, including cow’s milk allergy (CMA)6,7.  Compared with healthy babies, infants with CMA have an unbalanced gut microbiota with lower levels of bifidobacteria7.

Although it remains unclear exactly how gut microbiota dysbiosis leads to food allergies, studies suggest that the gut microbiota affects the immune system by changing the body’s metabolism and immune response1,4. It is possible therefore that infants with CMA, who more prone to infections8, may require not just effective resolution of their allergy symptoms but also a means of re-balancing their gut microbiota dysbiosis, which could be associated with a poorer functioning of their immune system. 

Early life: a key period for the developing gut microbiota

The first 1000 days of life present a critical window of opportunity for the development of a healthy gut microbiota9. A baby’s gut microbiota is changing over time and is fully matured by about three years of age10-12.

When the delicate balance of gut microbiota is disturbed during this sensitive period, it may increase the risk of disease, not only in infancy but also later in life9. Factors that can affect the gut microbiota in early life include1:

  • Type of birth. Vaginally born infants come into contact with a different microbiota than those born via C-section, ultimately affecting the composition of bacteria in their gut13.
  • Use of antibiotics. Some studies have shown that the use of antibiotics in early life changes and reduces gut microbiota diversity14.
  • Environmental factors. Exposure to chemicals and pollutants, through ingestion and/or inhalation, is believed to affect the composition of gut microbiota15-17.
  • Early life nutrition. Diet during the first months of life plays an important role in the establishment of gut microbiota, and may affect the development of allergies18.

Early nutrition and healthy gut microbiota

Breastmilk is the best possible nutrition for infants, not only containing all the nutrients they need for normal growth and development but also in its ability to shape the development of a healthy gut microbiota. It does this via the delivery of beneficial bacteria (e.g. Bifidobacterium), as well as carbohydrates called oligosaccharides that encourage the growth of those beneficial bacteria19-21. Breastfed infants tend to have a gut microbiota dominated by Bifidobacteria when compared with formula-fed infants9.

When a baby cannot feed exclusively on breastmilk, choosing a formula that is designed to support gut microbiota may help in the development of a balanced gut microbiota, and thereby may contribute to their overall health in the short and long term19-22.    

What is SYNEO and how does it help infants with CMA?   

SYNEO is the only CMA range to contain our unique mix of pre and probiotics that work together to support the immune system23-25.

  • beneficial bacteria Bifidobacterium breve, which comes from a family of bacterial species commonly found in breastmilk26,27 and which has been clinically proven to have an immune modulating effect28.
  • our trusted prebiotic oligosaccharide blends, scGOS/lcFOS (9:1) or scFOS/lcFOS (9:1) – which act as food for the beneficial bacteria29. The prebiotics in SYNEO have been researched in more than 30 scientific studies30,  and are proven to support healthy gut microbiota and immune system development26.

SYNEO has been clinically proven to re-balance the gut microbiota of infants with CMA to be closer to their healthy, breastfed peers with fewer reports of infections23-25,31. By adding SYNEO to our range of hypoallergenic formulas for CMA management, infants with CMA benefit from same effective symptom resolution as our standard range but clinical trials have also shown consistent signals on a broad range of other immune-related events, including: 

Fewer reported infections and antibiotic usage23,24,31,32.

Improved reports of skin symptoms and less use of dermatological medicine24,33.

Fewer reports of asthma-like symptoms– with babies having fewer asthma-like symptoms and less need for asthma medicine after one year28.

  1.     Jandhyala SM et al. World J Gastroenterol. 2015: 21(29); 8787–803.
  2.     Azad M, et al. Clin Exp Allergy 2015;45:632–43.
  3.     Kirjavainen P, et al. Gut 2002;51:51–5.
  4.     Valdes AM et al. BMJ 2018; 361: k2179.
  5.     Frati F et al. Int. J. Mol. Sci. 2019: 20; 123–34.
  6.     Lee et al. Clin Mol Allergy 2020: 18; 5–15.
  7.     Dong P et al. Saudi J Biol Sci. 2018: 25; 875–80.
  8.     Woicka-Kolejwa et al. 2016 (independent study)
  9.     Robertson RC et al. Trends Microbiol. 2019; 27(2): 131–47.
  10.     Wopereis H, et al. Pediatr Allergy Immunol, 2014;25:428-38
  11.     Scholtens PA, et al. Annu Rev Food Sci Technol, 2012;2:425-47
  12.     Arrieta MC, et al. Front Immunol, 2014;5:427
  13.     Neu J, et al. Clin Perinatol, 2011 ;38(2) :321-31
  14.     Ahmadizar F, et al. Pediatr Allergy Immunol, 2017;28(5):430-7
  15.     Patel MM, et al. Environ Res, 2011;111(8):1222-29
  16.     Ryan PH, et al. J Allergy Clin Immunol, 2005;116(2):279-84
  17.     Ryan PH, et al. Am J Respir Crit Care Med, 2009;180(11):1068-75
  18.     Berni Canani R, et al. Front Immunol, 2019 ;10 :191
  19.     Walker WA, et al. Pediatr Res. 2015; 77(1–2): 220–8.
  20.     Bergmann H, et al. British J Nutr. 2014; 112: 1119–28.
  21.     Hunt KM, et al. PLoS One 2011; 6(6): e21313.
  22.     Chua M, et al. JPGN 2017; 65: 102–6.
  23.     Burks A, et al. Pediatr Allergy Immunol, 2015 ;26(4) :316-22
  24.     Fox AT, et al. Clin Transl Allergy, 2019 ;9 :5.
  25.     Presto 2020
  26.     Moro G, et al. J Pediatr Gastroenertol Nutr. 2002; 34:291-5
  27.     Cuello-Garcia et al. World Allergy Organ J, 2016;9:1017
  28.     Van der Aa LB, et al. Allergy, 2011; 66: 170-7
  29.     Schouten B, et al. J Nutr. 2009; 139: 1398-403.
  30.     Data on file (placeholder)
  31.     Candy D, et al. Pediatri Res, 2018;83(3): 677-86
  32.     Chatchatee P, et al. EAACI Media Library 2019, available at
  33.     Harvey BM, et al. Pediatr Res, 2014 ;75(2): 343-51

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