The gut is not just about digestion, it is about how you age

Ask most people what the gut does, and they will mention digestion, maybe bloating, perhaps a food intolerance. Few would connect it to how sharp their memory is at sixty, how steady their mood is on a difficult week, or how their hormones behave in a stressful year. Yet increasingly, that is exactly the connection the evidence points to.

The simple explanation

Inside every digestive tract lives a vast community of bacteria, viruses and fungi, collectively known as the gut microbiome. In a young, healthy gut, this community is diverse: many different species, working in balance, supporting a strong gut lining and keeping inflammation low. As we age, that diversity tends to narrow. Less helpful bacteria gain ground, the gut lining weakens, and low-grade inflammation creeps in, a process researchers now call inflammaging.

Recent research from the US National Institute on Aging, drawing on data from more than 9,000 people, adds a striking detail. The adults who aged best were not the ones with the most textbook microbiome. They were the ones whose gut bacteria became more distinctly their own as they got older, developing patterns unlike anyone else’s. Those individuals walked faster, moved more easily, and needed fewer medications than their peers.

Why this matters to you

Inflammaging does not stay contained to the gut. It is linked to a wider set of conditions many patients come to us for: metabolic issues, mood changes, hormonal imbalance, joint and muscle decline, and slower cognitive recovery from stress. If the gut is quietly driving inflammation elsewhere in the body, addressing digestion in isolation, as conventional medicine often does, only ever tells part of the story.

This is also why patients so often describe the same experience: normal bloods, no clear diagnosis, and a nagging sense that something is still not right. The gut is rarely the first place anyone looks. It should be one of the first.

How we think about it

Gut health sits at the centre of the functional medicine pillar of our methodology, and it is a particular clinical interest of Dr Zia Knippenberg-Stratos, whose work focuses on the gut microbiome and the gut-brain axis.

“The gut is never really just about the gut,” she says. “It shapes immunity, metabolism, hormones, mood and cognition, often all at once. When we map what is happening there, we are usually finding the root of symptoms patients have been told are unrelated.”

Rather than treating digestive symptoms as a standalone complaint, we look at the gut as one input into a much larger picture, alongside hormonal, metabolic and longevity markers, because that is where the more useful answers tend to sit.

What you can do

You do not need to overhaul your life to support a healthier gut. The evidence points to a few consistent, unglamorous habits:

• Prioritise fibre-rich, whole foods. Vegetables, legumes, seeds and nuts feed the beneficial bacteria that support a strong gut lining.
• Limit ultra-processed and heavily sugared foods, increasingly linked to reduced microbial diversity.
• Move regularly. Exercise is one of the more consistent, evidence-backed supports for a healthy microbiome.
• Treat persistent digestive symptoms as data, not background noise. Bloating, irregularity or food reactions that someone has quietly lived with for years are often worth investigating properly, rather than managing indefinitely.
• Test your gut for its health and address any issues.

Where this is going

Gut testing has moved on considerably from a basic stool sample. We are expanding our partnership with GutMap, whose diagnostics allow for a more detailed picture of the microbiome than has previously been available in clinical practice. More on that shortly.

If you have been living with digestive symptoms, or simply want to understand what your gut is telling you about how you are ageing, book a consultation at The Schoeman Clinic.