Guide · Gut health
Gut microbiome tests: Zoe, Viome and what the evidence says
Stool tests that promise personalised nutrition from your gut bacteria are a £150 to £400 purchase. What they measure, what they cannot yet tell you, and the gut symptoms that need a doctor rather than a kit.
Updated September 2026 · Prices are UK list prices and need verification
This is general information, not medical advice. We are not doctors and this page has not been clinically reviewed. It cannot diagnose, treat or replace a consultation with a qualified clinician. If you are unwell, contact your GP or NHS 111; in an emergency call 999. Some links on this page are affiliate links; see our disclosure. Full medical disclaimer.
Tests
| Test | Price | What it measures | What you get | Evidence |
|---|---|---|---|---|
| Zoe | £299 start + £25 to £60/mo | Microbiome sequencing, blood fat, CGM | Food scores; programme; app | Company-led trials show behaviour change; microbiome scores not independently validated |
| Viome | £150 to £300 | Microbiome RNA | Food recommendations; supplements | Limited independent evidence |
| Atlas Biomed | £150 | Microbiome DNA | Diversity, food advice | Descriptive |
| Healthpath / Invivo (GI-MAP style) | £250 to £400 | Pathogens, parasites, markers | Practitioner report | Some markers clinically useful; often overinterpreted |
| NHS stool tests (FIT, calprotectin, culture) | Free via GP | Blood, inflammation, infection | Diagnosis of bowel disease | Well-evidenced; the tests that matter |
UK prices September 2026.
What a microbiome test can tell you
Which bacteria are present in a sample and in what proportions, and a diversity score. Higher diversity is associated with better health in population studies. That is roughly where the solid ground ends. The microbiome varies day to day, sample to sample and lab to lab; two tests a week apart from the same person can differ substantially.
What it cannot yet tell you
Which foods you personally should eat. The link between a specific bacterial profile and a specific dietary recommendation is not established for healthy people outside the companies’ own research. Zoe’s trials show that people following its programme change their behaviour and improve some markers; that is a good outcome for a nutrition programme, and it does not demonstrate that the microbiome score was the reason. The British Dietetic Association and gastroenterology bodies do not recommend commercial microbiome testing for the general public.
What actually improves gut health
Fibre from a wide range of plants, fermented foods, fewer ultra-processed foods, sleep, exercise and less alcohol. Every commercial test ends up recommending some version of this. You can do it for the price of vegetables.
The tests that matter
If you have gut symptoms, the tests with evidence are the NHS ones: FIT for hidden blood, calprotectin for inflammation, stool culture for infection, coeliac serology in blood. These diagnose bowel cancer, inflammatory bowel disease and coeliac disease. A microbiome kit does none of that and may delay you getting the test you need.
When to see a GP
- Blood in your stool, or black stool, at any age
- A change in bowel habit lasting more than three weeks
- Unexplained weight loss, persistent abdominal pain or bloating
- Diarrhoea waking you at night
- Family history of bowel cancer or inflammatory bowel disease
- Any of the above before buying a microbiome kit
NHS 111 online or by phone for urgent but non-emergency concerns. 999 for emergencies.
FAQs
Common questions
Is Zoe worth it?
As a structured nutrition programme with coaching, it changes behaviour for many people. As a microbiome test that tells you what to eat, the independent evidence is not there. Decide which you are buying.
Can a gut test diagnose IBS or IBD?
No. IBD is diagnosed with NHS tests (calprotectin, colonoscopy). IBS is diagnosed by excluding other causes. A commercial microbiome test does neither.
What is a good microbiome diversity score?
Higher is loosely associated with health, but there is no validated threshold and scores vary between samples and companies. Treat it as a curiosity.
How do I improve my gut microbiome?
Eat 30 or more different plant foods a week, include fermented foods, cut ultra-processed food and alcohol, sleep and move. No test required.
Sources
- NHS · Bowel cancer symptoms
- British Dietetic Association · gut health and probiotics
- British Society of Gastroenterology
- NICE NG12 · suspected cancer referral thresholds
The blood markers that reflect diet and metabolic health, explained.
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