Prebiotics and probiotics for babies: the role in infant nutrition

Supporting a baby’s gut health is one of the most important aspects of infant nutrition. From the earliest days of life, beneficial bacteria, prebiotics, and probiotics play a role in shaping the digestive system, immune function, and overall health. While breast milk naturally contains compounds that nurture a healthy gut microbiome, many families where exclusive breastfeeding is not possible, turn to infant formula, complementary feeding, and occasionally supplements to help maintain the right balance of healthy gut bacteria.

Prebiotics and probiotics help create a healthy gut environment for infants by supporting the growth of beneficial bacteria and promoting long-term health.

This article explores what prebiotics and probiotics are, how they work, when they may be introduced, and the differences between them, while answering common questions parents often ask.

Do babies need probiotics and prebiotics?

Not every baby needs probiotic or prebiotic supplements. For many, mother's milk provides everything required to develop a strong and healthy gut microbiota. Exclusive breastfeeding is recommended for optimal infant nutrition, as it supports immune system development, gut health, and overall growth. Mother's milk naturally contains human milk oligosaccharides (HMOs), which function as prebiotics by feeding beneficial gut bacteria. It also contains live bacteria that support the early development of a healthy digestive system, helping the gut microbiota of a breast fed infant develop optimally.

That said, in situations where breastfeeding is not possible, or where a baby experiences digestive discomfort, some parents and healthcare professionals consider probiotics and prebiotics as supportive options. Including prebiotics and probiotics in an infant's diet can help support gut health and development when exclusive breastfeeding is not an option. Some infant formulas are supplemented with prebiotics, probiotics, or a combination (called synbiotics), which may support digestive and immune development.

Do paediatricians recommend probiotics for babies?

Paediatricians often approach probiotics with caution. While they recognise the potential benefits of certain probiotic strains, they also emphasise that not all strains are equally effective or safe.

One example is Lactobacillus reuteri DSM 17938, a probiotic strain studied for its role in reducing colic symptoms in breastfed infants. However, this evidence does not automatically apply to all probiotics, and the use of supplements in infants should always be guided by a healthcare professional.

For formula-fed babies, evidence about probiotics is less conclusive. While some formulas include them, paediatricians usually recommend assessing the baby's specific needs before introducing supplements.

Do prebiotics help babies poop?

Yes, prebiotics can help support softer and more regular bowel movements. Prebiotics are non-digestible fibres that travel through the digestive system to the large intestine, where they are fermented by beneficial gut bacteria. This process encourages healthy stool consistency and can reduce constipation.

Clinical studies have shown that infant formulas supplemented with blends such as galacto-oligosaccharides (GOS) and fructo-oligosaccharides (FOS) in a 9:1 ratio can mimic the stool patterns of breastfed infants, promoting comfort and digestive health. For many babies, prebiotics play a gentle yet effective role in maintaining a healthy digestive system.

Some studies have investigated a potential link between prebiotics and gastrointestinal health, but evidence is still developing.

At what age can babies start taking probiotics?

The timing of introducing probiotics depends on individual circumstances. In most cases, probiotics are not needed before six months of age, unless specifically advised by a healthcare professional. This is because very young infants, particularly those born prematurely or with weakened immune systems, may be more vulnerable to potential risks associated with live bacteria.

When recommended, only well-researched probiotic strains with established safety profiles should be considered. For example, L. reuteri DSM 17938 has been studied in breastfed infants from birth. It is important to note that probiotics need to be consumed regularly to maintain their beneficial effects in the gut. However, decisions about probiotics should always be based on professional healthcare guidance and the baby’s specific health needs.

Can infants take prebiotics?

Yes. Prebiotics are safe and naturally present in breast milk in the form of HMOs. For babies who are formula-fed, many modern infant formulae are now supplemented with prebiotics such as GOS, FOS, or human-identical milk oligosaccharides like 2’-FL and LNnT. These ingredients feed beneficial gut bacteria, promoting balance and supporting the development of a healthy gut microbiome.

Prebiotics are indigestible by the human body and instead serve as nourishment for gut bacteria, helping to support digestive health. Unlike probiotics, which contain live bacteria, prebiotics act as nourishment for the bacteria already present in the infant’s gut. This makes them a gentle and widely accepted addition to infant nutrition.

The difference between prebiotics and probiotics

Understanding the difference is essential:

• Probiotics are live bacteria that, when consumed in adequate amounts, help establish or restore beneficial gut bacteria. They can be found in some infant formulas, drops, or supplements. Different probiotic strains can offer different health benefits for infants.
• Prebiotics are non-digestible fibres that stimulate the growth of good bacteria in the gut. Breast milk is naturally rich in prebiotics, and certain formulas include them to replicate this benefit.
• Synbiotics combine both, aiming for a synergistic effect, although research on their benefits in infants is still developing.

What are prebiotics?

Prebiotics are compounds that reach the large intestine undigested, where they serve as food for beneficial gut bacteria. Common examples include:

• Human milk oligosaccharides (HMOs): Found naturally in breast milk, these prebiotics play a central role in shaping an infant’s gut microbiota.
• Galacto-oligosaccharides (GOS) and Fructo-oligosaccharides (FOS): These are added to many infant formulas to mimic the effect of HMOs.
• Prebiotic foods: As part of a healthy diet for both adults and infants, prebiotic foods such as bananas, oats, and asparagus support gut health, especially when introduced during complementary feeding.
• Prebiotics are vital for maintaining a balance of good gut bacteria, supporting digestive health, and aiding immune development.

Prebiotics and probiotics for babies: supporting gut health

Digestive system

Both prebiotics and probiotics play an active role in establishing a healthy digestive system. Probiotics introduce live beneficial bacteria, while prebiotics provide the fuel these bacteria need to thrive. Together, they promote comfortable digestion, softer stools, and regular bowel movements.

Immune system

A large portion of the body’s immune cells reside in the gut. By supporting a healthy gut microbiome, prebiotics and probiotics contribute to the normal functioning of the immune system. This helps infants respond to environmental challenges and maintain resilience.

Infant nutrition

Certain infant formulas are supplemented with prebiotics or probiotics to support gut health, although composition differs from breast milk.

Breast milk and infant formula

• Breast milk naturally provides both prebiotics (HMOs) and live, friendly bacteria, creating the perfect foundation for a baby’s gut health. Human milk oligosaccharide is a key component of breast milk, supporting immune development and shaping the intestinal microbiota. Breastfed infants often display a predominance of Bifidobacteria, a beneficial strain strongly associated with digestive and immune well-being.
• Infant formula has advanced significantly, with many products now supplemented with prebiotics and probiotics. Infant formulas aim to more closely reflect the benefits of breast milk, although they are not identical.

The choice between breast milk, formula, or a combination will depend on each family’s circumstances, but both can play a role in supporting a baby’s gut microbiota and maintaining a healthy balance of gut bacteria.

Health benefits of a healthy gut microbiome

A balanced gut microbiome in infancy is linked to:

• Efficient digestion and nutrient absorption
• Comfortable bowel movements
• Development of a healthy immune system
• Support for overall well-being

The main health benefit of prebiotics and probiotics is supporting long-term well-being by promoting a healthy gut microbiome.

By encouraging the growth of healthy gut bacteria, prebiotics and probiotics may contribute to a smoother start to life, laying the foundation for long-term health.

Complementary feeding and solid foods

From around six months old, when solid foods are introduced, the infant gut microbiome undergoes further development. Complementary feeding introduces new types of fibres and nutrients, broadening the diversity of gut bacteria.

At this stage, certain foods naturally contain prebiotics and probiotics that support gut health. For example, prebiotic-rich foods such as oats, onions, garlic, and certain fruits can play a natural role in supporting gut health. These foods, combined with continued breast milk or formula, help establish a varied and resilient gut microbiota.

Practical guidance for parents and caregivers

1. Breastfeed if possible. Breast milk naturally supports gut health with HMOs and live bacteria.
2. Choose formula wisely. If using formula, look for options enriched with prebiotics or probiotics to support the development of healthy gut bacteria.
3. Seek professional advice. Always consult a healthcare professional before introducing probiotic supplements, particularly for newborns, preterm infants, or babies with health concerns.
4. Introduce solid foods gradually. From six months old, offer a variety of prebiotic-rich foods to continue supporting the microbiome.
5. Watch your baby’s cues. Every infant is unique, and digestive comfort can vary. Seek guidance if you notice ongoing concerns such as constipation, colic, or irregular bowel movements.

Summary table

Final thoughts

Prebiotics and probiotics play complementary roles in infant nutrition. While breast milk remains the gold standard, modern formulas enriched with these components provide valuable support when breastfeeding is not possible. Prebiotics are safe and effective for nurturing healthy gut bacteria, while probiotics may offer benefits in specific situations, particularly when guided by a healthcare professional.

The foundation of healthy gut microbiota during infancy helps support the digestive system, immune function, and overall well-being. Whether through breast milk, formula, or complementary feeding, nurturing beneficial gut bacteria from the earliest days is an investment in a child’s future health.

Disclaimer:

This article is for informational purposes only. It does not replace advice from a qualified healthcare professional. Always consult a paediatrician, midwife, or other healthcare provider before introducing probiotics, prebiotics, or supplements into an infant’s diet.