What Are GOS and FOS Prebiotics And Why Do We Need Them In Baby Formula?

Before we begin: Please note that probiotics, gut microbiota and gut flora are the same descriptors for live bacteria found in the intestine.


You may be wondering why GOS or FOS are present in your baby’s formula milk - and what makes these two ingredients so important in your little one’s formula-fed diet. Here at Kendamil, we’ve got you covered!


🤔 GOS and FOS: What Are They?

GOS (galacto-oligosaccharides) and FOS (fructo-oligosaccharides) are prebiotics. Prebiotics are the essential food source for intestinal flora (better known as gut microbiota - a complex system of bacteria which keep the gut, and the rest of the body, functioning). You will generally  find prebiotics in foods high in dietary fibre (including bananas, asparagus, tomatoes and leeks). Studies have shown that more gut microbiota in the intestinal tract means better immunity, stronger metabolism, less inflammation and, with recent research, better brain function. You will find GOS and FOS in Kendamil Classic Stages 1 and 2, while you will find GOS in Kendamil Classic Stage 3, Kendamil Organic Stages 1-3 and Kendamil Goat Stages 1-3.

Because your little one can’t eat solid foods, it’s important that their milk contains the right amount of prebiotics to help their intestinal flora thrive and grow. If you choose to breastfeed your little one, you’re feeding your baby natural, targeted prebiotics, known as Human Milk Oligosaccharides (HMOs). These HMOs shape an infant’s gut microbiota and help to modulate the ‘neonatal immunity in the infant gut’. 

For formula-fed little ones, their source of prebiotics are GOS and FOS - non-digestible carbohydrates which are added to baby formula. In fact, a comparative study on the metabolic activity of GOS/FOS fed babies and breastfed babies showed positive results, with the gut metabolic activity in formula-fed babies with GOS/FOS prebiotics shown to be similar to the gut metabolic activity of breastfed infants. Babies who were fed standard formula milk, without the addition of GOS/FOS prebiotics, had lower levels of this metabolic activity.

Long story, short? Prebiotics help your baby develop a healthy gut by feeding the beneficial bacteria in the GI tract. 


💪 The Gut-Immunity Connection.

Prebiotics, be they HMOs or GOS/FOS, help keep your baby’s gut healthy, providing the essential fibre that your little one needs to keep the gut metabolising. A young infant’s immune system is more vulnerable because their gut is less diverse than a fully formed adult’s, while normally your little one cannot get their essential prebiotics from solid foods until they start weaning. It’s therefore important to build up your little one’s gut flora to kickstart their immunity. 

You may be wondering “what’s the connection between a healthy gut and better immunity?”. 

The relationship between the gut and immune system is a strong one. Our intestines contain more immune cells than anywhere else in the body. In fact, 80% of our immune system is located in our digestive tract! Our gut contains a thin wall of cells that maintains a barrier between the intestine and the rest of the bloodstream. Behind that barrier are cells which link to the immune system. These cells are responsible for the immune response. 

So, more prebiotics in a little one’s (or anyone’s!) diet means that the gut bacteria in our GI tract can grow. Bacteria feed on prebiotics and essentially multiply. More healthy gut bacteria means a stronger lining, better immune cell function and quicker immune response. Less of this gut bacteria can lead to greater inflammation.


📝 ✅ To Conclude.

  • HMOs and GOS/FOS are prebiotics
  • Prebiotics are a food source for gut flora (live bacteria)
  • Prebiotics are recognised as beneficial in maintaining infant immunity
  • More prebiotics means more essential gut flora to keep a baby’s GI tract healthy and inflammation low

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