What every parent really needs to know about probiotics for kids

By Lucy Upton, Specialist Paediatric Dietitian

There is no doubt that gut health is a big buzzword at the moment, and with this comes the inevitable influx of advice, product recommendations, and sometimes conflicting information, especially when it comes to children. Probiotics are one of the most discussed topics in this area, often marketed to you as a simple solution or fix for everything from tummy troubles to immune ‘boosting’. But what are probiotics, do your kids really need them, and how do you actually know what’s safe or effective?

What are probiotics?

Put simply, probiotics are live microorganisms (like bacteria, but also some yeasts) that can provide health benefits when consumed in the right amounts.  Probiotics are not to be confused with prebiotics.  Prebiotics are the food or fuel for good gut bacteria, and typically this is fibre!  

The gut microbiome consists of trillions of bacteria, and maintaining the right balance can significantly impact health. I often compare the gut microbiome to a garden. We want a diverse collection of flowers and plants, but without too many weeds. Similarly, the goal is to have a diverse and thriving range of beneficial gut bacteria while keeping harmful bacteria at bay. When the bacterial balance shifts, with more ‘weeds’ and fewer ‘flowers’, it is often referred to as gut dysbiosis. Probiotics can support this balance and are often helpful after illness, antibiotic use, or during other periods of gut disruption.

How can probiotics support children’s gut health?

Children’s gut health is important, and is about much more than good digestion.  The balance of bacteria in a child’s gut can impact their immune health, brain health and mood, metabolism and even risk of long-term disease.  Arguably, childhood, and the earlier the better, is the time to optimise gut health as the army of bacteria your child accumulates during early life, especially the first 3-5 years, will be one that comes with them for life.

Lots of factors impact a child’s gut microbiome, from mode of delivery to medication use and even whether there are furry friends at home.  One of the biggest modifiable factors parents can influence is a child’s diet, as this has a significant impact on the gut microbiome.  The gut’s golden fuel will always be plant-based foods, which provide a variety of fibre sources and other nutrients like antioxidants – so offering a wide variety of fruits, vegetables, whole grains, beans, and seeds really matters.  Alongside this, the use of probiotics may offer additional support.

Where can you find probiotics?

Generally there are three key sources of probiotics for children, which are as follows.

Breastmilk	Breastmilk is a living and dynamic fluid, and contains a huge number of different bacteria (the breastmilk biome) which positively support a child’s gut health
Fermented foods	Some foods naturally contain live bacteria, usually produced as a result of the fermentation process.  These include options like kefir (fermented milk), live yoghurt, kimchi, some cheeses (aged), sauerkraut. Many of these have been found to positively support gut health
Probiotic supplements	There are now a wide range of probiotic supplements on the market, which contain one or more strains of bacteria.  These are not all the same, and may not all have the same effect.  Find out more next.

Are all probiotic supplements the same?

Unfortunately, I’m afraid not. With the rise in our understanding and focus on gut health, the supplement arena has become saturated with a wide range of probiotic options, and they are not all created equal!

The first thing that’s essential to understand about probiotic supplements is that different strains of bacteria do different jobs. Picking a supplement at random risks choosing one that may not have any benefit for the health concern you’re trying to address – or worse, may not be suitable for your child at all.

When looking for a probiotic, it’s important to check for:

 Red flags to watch for:

1. Lack of robust studies to support the health claim being made
2. Vague strain listings, like “Lactobacillus” or “Bifidobacterium”, instead of precise strains such as Limosilactobacillus reuteri DSM17938 (which has been well-studied for infant colic, for example)
3. No (or a low) CFU count (colony forming units), expiry dates, or storage guidance
4. Over-promising on benefits, especially if it’s not backed by science
5. Products are marketed heavily on social media without clinical backing

Choosing a probiotic because it’s been upsold by an influencer or fronted by fancy packaging can be tempting, but I’m afraid it’s not a replacement for science-backed decisions.

How to choose a probiotic supplement?

The first thing to understand about probiotic supplementation is that there is limited evidence that probiotic supplementation in a healthy child is going to provide any benefit!  They are, of course, considered safe, but the first question to ask is “Why am I giving my child this supplement?”.

If you do want to explore supplementation, the next thing you want to look for is specific strains that have been clinically studied in children for the outcome you’re aiming to support, e.g. tummy pain, colic, immune health, e.g. reduced respiratory infections, antibiotic-associated diarrhoea.  To help support this decision-making, here are some common tummy or gut complaints in children, and the bacterial strains that are evidence-based to help;

	Bacteria strains	Comments
Colic	Limosilactobacillus reuteri DSM17938	Best evidence of benefit is in breastfed babies
Antibiotic associated diarrhoea	Lactobacillus rhamnosus GG OR Saccharomyces boulardii	Start alongside antibiotics and continue for the course.
Functional abdominal pain	Limosilactobacillus reuteri DSM17938	May reduce frequency/intensity of pain. Use daily over at least 4 weeks
Immune health e.g. reduce chest infections, infection prevention	Lactobacillus rhamnosus GG OR Limosilactobacillus reuteri DSM17938	May reduce days off nursery/school and upper respiratory tract infections
Oral health	Limosilactobacillus reuteri DSM17938And  L.reuteri ATCC PTA 5289	Supports a balanced oral microbiota

To find products containing these specific bacteria, you can simply look up the strain carefully online and search for child-specific formats, for example, drops, powders, or chewables, depending on your child’s age and preference. Always check the strain code, not just the species name, as this is what determines whether the product is backed by clinical research.

Remember, as a general rule, to observe any potential benefit, you’d want to trial a probiotic daily for at least 4 weeks – consistency is key!  It’s also worth noting that some strains are patent-protected, meaning they are only found in one company’s product. For example, Limosilactobacillus reuteri DSM17938 is the key strain used in BioGaia products.

If you’re unsure whether your child might benefit from a probiotic, it’s always best to speak to a registered dietitian or healthcare professional who understands the science and can guide you in making the right choice. Just remember, there is probably no benefit it picking one at random!