A group of kids with their arms around each others shoulders smiling and laughing

The ages and stages of gut health development in children

Having good gut health and a strong microbiome is increasingly well recognised as being essential to our overall health and wellbeing. Laying the foundation of good gut health throughout childhood from babies to teenagers is therefore one of the best ways to support kids’ health in the short term as well as help them thrive later in life.

Why is gut health important in kids?

There are many reasons why having good gut health and a robust microbiome are important for kids.



The bacteria that make up the gut microbiome play a key role in the digestive process. They help to break down starches and fibres that aren’t easily digested by the body, which results in the production of important short-chain fatty acids. These serve as an energy source for the cells that line the intestines, play a role in balancing inflammation and support the regulation of fat and glucose metabolism.1


Nutrient production

Gut bacteria can synthesise important B vitamins and provide up to half the daily requirement of vitamin K2, a nutrient needed for healthy bones and blood.


Immune health 

Much of the body’s immune system resides in the gut and depends on the gut microbiome. The gut microbiome provides protection from pathogens (viruses, bacteria, fungi etc) that enter the body, helping reduce the risk of infection. It also helps balance inflammatory responses and directly impacts the health of the gut barrier wall, which plays an important role in defending against illness.3


Brain health and function

The gut communicates directly with the brain and can actually affect mood and brain function.4


What is the importance of good gut health in each age and stage of childhood?



The gut microbiome is mostly shaped in the first few years of life, providing a crucial window of opportunity for establishing a healthy gut community and subsequent good health.5 The makeup of a baby’s microbiome comes from the mother (via birth and breastfeeding), diet and the surrounding environment. Building a diverse gut microbiome early on can have a ripple effect on other areas of development like immunity and digestive wellbeing.



As babies turn into toddlers, their gut microbiome continues to evolve and lay the foundations of health for later life. Since kids’ systems are still developing, they are more vulnerable to their environment. As they explore different foods they may experience digestive discomfort and as they are exposed to more social situations, they are usually more prone to sickness. Helping establish a healthy gut community and good gut health in the toddler years can have wide ranging benefits for their digestion and immunity as they grow and develop.


Primary school children

Although most of the development of the gut microbiome occurs within a child’s first few years, it continues to evolve as they get older. Primary school aged children are still susceptible to frequent illness and might be prescribed antibiotics, which can reduce the abundance and diversity of bacteria in their gut.



Maintaining good gut health throughout the teenage years is not only important for healthy digestion and immunity. There is evidence to suggest that gut microbes can influence skin health and reduce acne, by inhibiting the growth of bacteria and helping balance the inflammatory response. It can also have an impact on emotional and mental well-being.4


How to maintain good gut health in children

There are many different ways you can influence good gut health throughout the ages and stages of childhood:



Including naturally fermented foods, rich in good bacteria, like yoghurt, miso, sauerkraut, kefir and kombucha can help influence the diversity of your child’s microbiome. Providing prebiotic-fibre rich foods like bananas, oats, artichokes, leeks, brown rice, garlic, sweet potato, asparagus, beans and legumes can help feed and nourish the bacteria in their gut and help keep the digestive system running smoothly.



Letting kids play outside, get their hands dirty and cuddle their pets can do wonders for their gut health and immunity.


Probiotic supplements

You might consider giving your child a probiotic supplement to support their gut and overall health, especially following a course of antibiotics, to help strengthen their immunity and reduce the occurrence of upper respiratory tract infection symptoms and maintain healthy digestion. Inner Health has a range of kid-friendly probiotics with research-backed strains to support a child’s needs at every age and stage.


What are the signs that something might not be quite right?

There are a number of symptoms that could indicate your child’s gut might not be functioning as well as it could be. These include regular stomach aches, uncomfortable digestion with bloating and wind, digestive system issues such as regular constipation or diarrhoea, low energy and frequent sickness. See your GP or a pharmacist about your concerns, who might prescribe a probiotic to support your child’s digestive health.



  1. den Besten G et al, 2013, ‘The role of short-chain fatty acids in the interplay between diet, gut microbiota, and host energy metabolism’, Journal of lipid research 54, no 9, pp 2325-40
  2. Hill MJ, 1997, ‘Intestinal flora and endogenous vitamin synthesis’, Eur J Cancer Prev, vol 6, Suppl 1, pp 43–5
  3. Takiishi, T et al, 2017, ‘Intestinal barrier and gut microbiota: Shaping our immune responses throughout life’, Tissue barriersvol 5, no 4
  4. Strandwitz P 2018, ‘Neurotransmitter modulation by the gut microbiota’, Brain research, vol 1693, Pt B, pp 128-133
  5. Rodríguez JM et al, 2015, ‘The composition of the gut microbiota throughout life, with an emphasis on early life’, Microbial ecology in health and disease, 26, 26050
  6. Rinaldi F et al, 2022, ‘Facial acne: a randomized, double-blind, placebo-controlled Study on the clinical efficacy of a symbiotic dietary supplement, Dermatol Ther (Heidelb). Vol 12, no 2, pp577-589
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