Prebiotics are non-digestible fibers that serve as a food source for beneficial gut bacteria. These compounds pass through the upper digestive system without being broken down, reaching the colon intact. In the large intestine, prebiotics are fermented by gut microorganisms, nourishing beneficial microbes. This process supports a healthy gut microbiome, which contributes to overall well-being.
Understanding Infant Prebiotics
In infants, prebiotics are non-digestible carbohydrates, primarily oligosaccharides, that stimulate the growth of beneficial bacteria in their developing gut. These include galactooligosaccharides (GOS) and fructooligosaccharides (FOS). Human milk naturally contains these prebiotics, known as Human Milk Oligosaccharides (HMOs), which are structurally diverse and highly abundant. HMOs are the third most prevalent solid component in breast milk after lactose and lipids, making them a significant part of an infant’s early nutrition.
These oligosaccharides are resistant to digestion by the infant’s enzymes, reaching the large intestine to be fermented by beneficial bacteria like Bifidobacterium. While GOS and FOS are simpler in structure compared to HMOs, they are often added to infant formulas to mimic some prebiotic effects seen in breastfed infants. The presence of these non-digestible fibers helps to shape the infant’s gut microbiota, encouraging the growth of a healthy bacterial population from early in life.
How Infant Prebiotics Support Health
Infant prebiotics help develop a healthy gut microbiota, supporting several aspects of an infant’s health. They promote the growth of beneficial bacteria, particularly Bifidobacteria, which are abundant in breastfed infants. This contributes to a balanced gut environment, important for digestive function and nutrient absorption.
Prebiotics also contribute to the development and function of the infant’s immune system. Approximately 70% of the immune system resides in the gut, and a well-supported microbiome can help regulate immune responses and potentially reduce inflammation. Research suggests that prebiotics, particularly HMOs, may help manage allergic conditions like eczema by influencing the immune system and strengthening the gut barrier. Some studies indicate that prebiotic supplementation in infant feeds may reduce the incidence or severity of eczema in infants up to two years of age.
Prebiotics aid in maintaining healthy stool consistency and can help reduce instances of constipation in infants. The fermentation of prebiotics by gut bacteria produces beneficial byproducts, such as short-chain fatty acids, which help maintain a strong gut lining and support overall health.
Where Infants Get Prebiotics
The primary natural source of prebiotics for infants is breast milk, which contains Human Milk Oligosaccharides (HMOs). The concentration of HMOs varies, with higher levels (approximately 20-25 g/L) found in colostrum, the milk produced immediately after birth, and around 10-15 g/L in mature breast milk.
For formula-fed infants, many infant formulas are fortified with prebiotics like galactooligosaccharides (GOS) and fructooligosaccharides (FOS). While GOS and FOS structures are not identical to HMOs, their inclusion helps foster a gut environment closer to that of breastfed infants.
Prebiotic supplements for infants also exist, often containing GOS, FOS, or synthetic HMOs like 2′-Fucosyllactose (2′-FL). These supplements are designed to provide additional prebiotic support. Before considering any prebiotic supplement for an infant, consult a pediatrician to ensure it is appropriate and safe.
Prebiotics Compared to Probiotics
Prebiotics and probiotics are often discussed together in the context of gut health, but they serve different functions. Prebiotics are non-digestible food components that act as “food” for beneficial microorganisms already present in the gut. They are not living organisms themselves but rather substrates that selectively promote the growth and activity of advantageous gut bacteria.
In contrast, probiotics are live beneficial microorganisms, such as certain strains of bacteria or yeasts, that, when consumed in adequate amounts, can provide health benefits to the host. These living microbes can help populate the gut with advantageous bacteria and contribute to a balanced microbiome. Common probiotic strains include various species of Lactobacillus and Bifidobacterium.
While distinct, prebiotics and probiotics can work together to support gut health, a concept sometimes referred to as synbiotics. Prebiotics provide the necessary nourishment for probiotics to thrive and function effectively within the digestive tract. This collaborative action helps maintain a diverse and healthy gut microbiota, contributing to overall well-being.