Is your child sick more often than other kids?

Frequent illness in children is not always just bad luck. The gut microbiome plays a more significant role in immune resilience than most people realise.

By Antonia Ghuman, Paediatric Naturopath  |  5 min read

Some children sail through winter without so much as a runny nose. Others seem to pick up every bug that comes through the school gate, take forever to recover, and are back with something new just a few weeks later.

Parents of these kids are often told it is just what happens at this age, or that exposure builds immunity. And while there is some truth to that, frequent illness is not always simply a numbers game. For many children, there is something driving the susceptibility.

Most of the immune system lives in the gut

This surprises most people. We tend to think of immunity as something that lives in the bloodstream or the lymph nodes. But the gut is where the vast majority of immune activity actually happens.

70%

of immune tissue is found in the gut lining

Research: Kers et al., Microorganisms, 2026

The gut-associated lymphoid tissue, along with the trillions of microorganisms living in the intestinal tract, play a central role in how the immune system learns to function. A healthy, diverse gut microbiome supports a more resilient and well-regulated immune response.

The gut teaches the immune system how to work

In early life, the gut microbiome essentially educates the immune system. It shapes innate immunity, trains antigen presentation, and helps the body learn the critical difference between things that are genuinely dangerous and things that are safe.

When that process is disrupted early on, the immune system can be left less able to mount appropriate responses. It may overreact to things that are harmless, like food proteins or environmental triggers. Or it may underreact when a genuine threat is present, leading to infections that linger or recur.

Research: Kers et al., Microorganisms, 2026

Factors that can reduce immune resilience from the start

Several things that happen in the very early stages of life can affect the composition of the gut microbiome and, as a result, how well the immune system develops. None of these are parenting failures. They are medical realities worth being aware of.

• Caesarean birth, which bypasses the initial microbial seeding that happens during vaginal delivery

• Early or repeated antibiotic use, which can deplete beneficial bacteria at critical developmental stages

• Formula feeding from birth, which delivers a different microbial and nutritional profile than breast milk

• Limited dietary diversity in the first few years, which reduces the range of bacteria that can establish in the gut

Research: Rezai et al., Archives of Clinical Infectious Diseases, 2025

The first three years set the immune baseline

Research consistently shows that the early-life gut microbiome is one of the most significant determinants of long-term immune health. Disruptions during the first three years are associated with an increased risk of asthma, food allergies, eczema, and ongoing inflammatory conditions.

0 to 3

years is the critical window for immune system education via the gut

Research: Nieselt-Struwe et al., Gut Microbes, 2025

That does not mean children with these risk factors are locked into a particular health trajectory. Early identification and targeted support can make a meaningful difference, especially during these early years when the system is still highly plastic.

Frequent illness is worth investigating, not just managing. There is often a clear reason why some children are more susceptible than others.

What we look at in clinic

When a family comes to us with a child who is frequently unwell, we look at the full picture. Gut microbiome testing, nutritional markers, inflammatory indicators, and the child's early history all factor into our assessment.

Understanding the specific drivers means the support we put in place is targeted and meaningful, rather than a broad supplement protocol that may or may not address what is actually going on.

Frequent illness is worth investigating, not just managing. We work with families across Australia via Telehealth.

Book a Telehealth consult via the link below

Antonia Ghuman

Paediatric Naturopath  |  The Neuromed Clinic

Master of Neuroscience  |  BHSc Naturopathy