The Importance of the Microbiome: Looking After Your Gut Health

Your gut is home to trillions of microorganisms, including bacteria, viruses and fungi. Together with their genetic material, these form your gut microbiome—a complex community that plays an important role in how your body functions.

At Cardiff Wellness Centre, gut health forms part of our wider interest in lifestyle and wellbeing. Understanding your microbiome starts with knowing what it does and which everyday choices can support digestive health.

Why does the microbiome matter?

The microorganisms in your gut are active participants in digestion. They help break down food components, and bacteria in the large intestine produce vitamin K. They work alongside your digestive organs to process what you eat. Learn how digestion works from the NIDDK.

Their influence extends beyond digestion. Researchers are studying how gut microbes interact with the immune system, the intestinal lining and the processes involved in metabolism. These relationships help explain why the microbiome attracts so much scientific interest. NIDDK microbiome research.

However, finding a link between particular microbes and a health condition does not automatically mean those microbes cause it—or that changing them will treat it.

What ZOE’s “top 50” gut microbes tell us

Research involving ZOE and academic collaborators has helped identify which gut microbes are associated with more favourable health measures.

Using more than 34,000 stool samples, the team developed a ranking that includes 50 bacterial species associated with favourable health markers and 50 associated with less favourable markers. Many of the favourable species were previously poorly characterised, showing how much there is still to discover about the gut ecosystem. Read ZOE’s explanation of the research.

The underlying study, published in Nature, ranked 661 commonly detected microbial species against measures including blood pressure, blood fats, glucose and responses after eating. This offers a more detailed picture than simply counting how many different microbes someone has. Read the original study in Nature.

The “top 50” should be understood as a research ranking, rather than a shopping list of bacteria everyone needs to take as supplements. Having particular microbes does not guarantee good health, and these associations do not establish that adding an individual species will prevent disease.

For readers, the useful message is that the composition of the gut community matters—and that nutrition research is moving towards understanding the roles of specific organisms within that community.

The Bologna study: the microbiome of people living beyond 100

Could the gut microbiome help explain exceptional longevity?

Researchers from the University of Bologna and collaborators explored this question in a study published in Current Biology. They compared younger adults, older adults and centenarians with a group of 24 people aged 105–109.

The researchers highlighted enrichment or greater prevalence of three potentially health-associated bacterial groups in exceptionally long-lived participants:

• Akkermansia (tested for at CWC)

• Bifidobacterium (tested for at CWC)

• Christensenellaceae

These are broader bacterial groups: the first two are genera, while Christensenellaceae is a family. The study did not establish a set of four individual species responsible for living beyond 100. Read Gut Microbiota and Extreme Longevity.

The findings suggest that the microbiome may adapt in distinctive ways during extreme ageing. However, this was an observational comparison: it cannot tell us whether those microbes helped people live longer or became more common because of their diet, genetics, environment or other features of ageing.

The research provides a valuable direction for future studies, but it does not show that taking these bacteria as supplements extends human lifespan.

The connection between your gut and brain

The gut and brain communicate through a network of nerves and chemical signals. Scientists are investigating how microorganisms contribute to this communication, often called the gut–brain axis.

It is an exciting research area, but claims that a particular supplement can reliably improve mood or treat anxiety by changing gut bacteria go beyond what we can confidently promise. Explore the NIDDK’s research priorities.

Start with what is on your plate

A practical starting point for digestive health is a varied diet containing enough fibre. The NHS recommends that most adults aim for 30g of fibre each day, from a range of foods.

Simple ways to increase your intake include:

• Choosing porridge or wholegrain breakfast cereals.

• Adding beans, lentils or chickpeas to soups and main meals.

• Including vegetables with lunch and dinner.

• Choosing wholemeal bread and wholewheat pasta.

• Enjoying fruit, nuts or seeds as snacks, where suitable.

These foods provide different types of fibre alongside other nutrients. NHS advice on increasing dietary fibre.

Fibre can help prevent constipation, and drinking enough fluid helps it do its job. If you have IBS or another digestive condition, the type and amount you tolerate may differ, so personalised advice can be helpful. NHS guidance on foods that support digestion.

Do you need probiotics?

Probiotics contain live bacteria or yeasts and are available in some foods and supplements. There is evidence that certain probiotics may help in particular circumstances, including some IBS symptoms.

However, benefits depend on the specific product and the condition being treated. A probiotic that helps one problem may not help another, and many broad marketing claims lack strong evidence. Anyone with an existing health condition or weakened immune system should speak to a doctor before taking probiotic supplements. NHS advice on probiotics.

What can microbiome testing tell you?

Microbiome testing can describe microorganisms detected in a stool sample. Turning that information into reliable treatment advice is more complicated.

Research such as ZOE’s ranking and the Bologna study adds to our understanding, but a microbial profile alone cannot establish your overall health or predict how long you will live.

Before choosing a test, ask what clinical question it will answer and whether the result is likely to change your care.

Gut health at Cardiff Wellness Centre

Cardiff Wellness Centre offers lifestyle consultations and access to microbiome testing. A consultation provides an opportunity to discuss your symptoms, diet and medical history, including whether testing would be useful and what its limitations are. Find out about our services.

Looking after your gut can begin with manageable changes to everyday meals. If you have ongoing digestive concerns, contact dr.j@cardiffwellnesscentre.com to discuss an assessment and your next steps.