Your gut is home to trillions of microbes — bacteria, fungi and other organisms that help digest food, train your immune system and produce vitamins and short-chain fatty acids. Collectively they are known as the microbiome, and interest in testing it has grown quickly. A gut microbiome test uses a small stool sample to build a picture of which organisms live in your gut and how well the system seems to be working.
What the test actually measures
A comprehensive microbiome analysis looks at far more than a simple "good versus bad bacteria" score. Depending on the panel, it can report on the diversity and balance of the organisms present and on markers that reflect how the gut is functioning:
- Bacterial diversity and balance — a wide range of species is generally associated with a healthier, more resilient gut.
- Fungal and yeast levels — an overgrowth of yeasts such as Candida can sometimes be flagged.
- Digestion and absorption markers — clues to how well you are breaking down fats, proteins and carbohydrates.
- Inflammation markers — such as calprotectin, which can point to inflammation in the bowel wall.
- Gut barrier and immune markers — indicators of how well the gut lining is holding up.
How the sample is collected
Most microbiome tests are done at home. You collect a small stool sample using the kit provided, seal it and post it back to the laboratory. There is no blood draw and no need to attend a clinic, which many people find convenient and discreet. Results usually take a couple of weeks because the laboratory analysis is more involved than a routine blood test.
Who might find it useful
People often consider microbiome testing when they have ongoing digestive symptoms — bloating, irregular bowel habits, discomfort — that have not been fully explained, or when they simply want to understand their gut health and tailor their diet. It can be a helpful starting point for conversations about fibre, fermented foods and variety in the diet.
That said, the science is still evolving. There is no single agreed definition of a "perfect" microbiome, and results should be interpreted thoughtfully rather than taken as a verdict.
Test your gut microbiome
A comprehensive stool-based gut microbiome analysis mapping the bacteria, fungi and functional markers that shape your gut health — collected at home and posted back to the lab.
Book a microbiome testWhat it cannot tell you
A microbiome test is not a screen for serious bowel disease. It will not reliably diagnose conditions such as coeliac disease, inflammatory bowel disease or bowel cancer. If you have red-flag symptoms — rectal bleeding, unexplained weight loss, a persistent change in bowel habit, difficulty swallowing, or anaemia — you should see a doctor promptly rather than relying on a microbiome report. These symptoms need proper medical assessment.
Making the most of your results
The most valuable part of microbiome testing is often what you do next: eating a wider variety of plant foods, increasing fibre gradually, and including fermented foods can all support a diverse microbiome. Reviewing your results with a clinician or dietitian helps turn the data into practical, safe changes rather than restrictive fad diets.
Test your gut microbiome
Book online with OneMedicine — CQC-registered clinic in Birmingham, or a home visit / local clinic nationwide. Doctor-reviewed results, most within 24 hours.
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Specialist interest: Cardiovascular Medicine · OneMedicine, CQC-registered clinic