Gut Microbiome Tests UK 2026: Are They Worth It? (Honest Review)

Written and medically reviewed by Dr Zeeshan Afzal | Last updated: July 2026 | Reading time: approx. 14 minutes

Gut microbiome testing has become one of the fastest-growing corners of UK consumer health. For somewhere between £100 and £400, a company will sequence the bacteria in a stool sample and send back a colourful report telling you how "diverse" your gut is, which microbes you are missing, and — almost always — which supplements you should buy. If you have arrived here searching for a gut microbiome test UK option, you almost certainly want a straight answer to one question: is it actually worth the money? This is an honest, evidence-led review. Before we go further, it is worth being clear about where the real leverage sits. Most of what improves your gut is behavioural and nutritional, not diagnostic. If you want to start with foundations rather than data, our complete UK gut health guide is the best place to begin, alongside the Welzo gut health range and our clinically formulated probiotic supplements. For readers who already know what they are looking for, targeted options include Akkermansia muciniphila, modified citrus pectin powder, Welzo Ultra Purity Berberine and Welzo Ultra Purity TUDCA. It is also worth reading our companion pieces on microbiome diversity, gut dysbiosis and our side-by-side microbiome test comparison.

Image: "Gut microbiota" via Wikimedia Commons, licensed CC BY 4.0.

The Short Answer: Are Gut Microbiome Tests Worth It in 2026?

For most people in the UK, a direct-to-consumer gut microbiome test is an interesting purchase rather than a necessary one. It will not diagnose a disease, it cannot be used to rule anything out, and two different companies analysing the same stool sample can return meaningfully different answers.

That is not a fringe opinion. In 2025, an international consensus statement published in The Lancet Gastroenterology & Hepatology, developed by 69 experts across 18 countries, concluded that there is insufficient evidence to recommend routine microbiome testing in clinical practice, and explicitly discouraged consumers from self-requesting these tests without a clinical reason.

Where these tests can earn their keep is narrower but real: as a structured motivator for dietary change, as a way of tracking your own trend over time using the same laboratory, and as a source of raw sequencing data if you are working with a qualified practitioner. What they should never be is your first move when you have symptoms. That is what NHS-validated testing is for.

Quick Verdict Summary

Table of Contents

• What Is a Gut Microbiome Test?
• Sequencing Methods Explained: 16S vs Shotgun vs RNA
• The UK Gut Microbiome Test Market in 2026
• Are Gut Microbiome Tests Accurate? What the Evidence Says
• What a Gut Microbiome Test Can Usefully Tell You
• What It Cannot Tell You (And the Red Flags to Watch)
• NHS and Validated Tests to Consider First
• Cost vs Value: The Money Question
• Data Privacy: Who Owns Your Microbiome Data?
• How to Choose a Gut Microbiome Test in the UK
• What to Actually Do With Your Results
• How to Improve Your Gut Without Testing at All
• Our Final Verdict
• Frequently Asked Questions
• References

What Is a Gut Microbiome Test?

A gut microbiome test is a stool test that identifies the microorganisms living in your large intestine. You collect a small faecal sample at home using a swab or scoop, seal it into a stabilising buffer, and post it to a laboratory. There, DNA (or in some cases RNA) is extracted from the sample, sequenced, and matched against a reference database of known microbial genomes.

The output is usually presented as a percentage breakdown of bacterial groups, a "diversity score", and a set of interpretations — often framed as your gut's ability to produce short-chain fatty acids, break down fibre, or maintain gut barrier function.

What a Stool Test Actually Measures

This is the first thing to understand, because it changes how much weight the result deserves. A stool sample tells you about the microbes that have been shed into the faecal stream from the distal colon. It does not directly sample the small intestine, the mucosal layer where much of the immunologically important activity happens, or the biofilm adhering to the gut wall.

It is a snapshot, taken from the exit, of a moving ecosystem containing hundreds of species. Your microbiome shifts with what you ate this week, whether you have travelled, your sleep, your stress levels, your bowel transit time and whether you have recently taken antibiotics. Two samples from the same person a fortnight apart can look noticeably different.

What "Diversity" Means and Why It Is Not a Grade

Most reports lead with a diversity score. Broadly, higher microbial richness is associated with better health outcomes at a population level, and low diversity has been associated with a range of conditions. But "associated with" is doing a great deal of work in that sentence. There is no validated cut-off above which you are healthy and below which you are not, and diversity alone tells you nothing about whether the species present are doing anything useful.

Read our detailed explainer on what microbiome diversity actually means and our practical guide to increasing gut bacteria diversity if you want to go deeper.

Sequencing Methods Explained: 16S vs Shotgun vs RNA

Image: Illumina HiSeq 2000 sequencers, BGI Hong Kong, via Wikimedia Commons, licensed CC BY 3.0.

The sequencing method a company uses is the single biggest technical determinant of what your report can legitimately say. It is also the detail most heavily buried in marketing copy.

16S rRNA Sequencing

This method amplifies a specific, highly conserved bacterial gene (the 16S ribosomal RNA gene) and uses variation within it to identify organisms. It is cheap, fast and well established. Its limitation is resolution: it typically identifies bacteria reliably only down to genus level, not species or strain. It also detects bacteria only — not fungi, archaea or viruses.

This matters enormously, because probiotic effects are strain-specific. Knowing you have "some Lactobacillus" tells you very little. Our guide to choosing a probiotic explains why strain designation is the detail that counts.

Shotgun Metagenomic Sequencing

Here, all DNA in the sample is fragmented and sequenced, then computationally reassembled. This gives species-level and sometimes strain-level identification, includes non-bacterial organisms, and allows inference of functional potential — which metabolic genes are present in the community. It is substantially more expensive and generates far more data.

An important caveat: functional potential is not functional activity. A gene being present does not mean it is being expressed.

RNA (Metatranscriptomic) Sequencing

A small number of providers sequence RNA rather than DNA, on the basis that this reflects genes actively being transcribed. In principle this is closer to measuring activity. In practice, RNA is fragile, degrades quickly, and the clinical interpretation frameworks built on top of it are largely proprietary and not independently validated.

Comparison of Sequencing Methods

The UK Gut Microbiome Test Market in 2026

Image: at-home microbiome sequencing sample kit, via Wikimedia Commons, CC BY 2.0.

The UK market splits into three broad tiers: consumer nutrition programmes, standalone consumer sequencing tests, and practitioner-ordered functional stool panels. Prices below reflect publicly listed information at the time of writing and change frequently — always check directly before ordering.

ZOE

ZOE is the best-known UK option, founded by Professor Tim Spector at King's College London. It combines stool sequencing with an app that generates personalised food scores. Notably, in September 2025 ZOE substantially changed the product: the continuous glucose monitor and the blood fat ("blue muffin") test were removed, leaving the gut microbiome test as the core measurement, with AI-driven food logging added to the app.

According to Which?, as of April 2026 the main route in is a bundle combining the gut test kit at around £149 with a 12-month app membership at approximately £9.99 per month. ZOE also flags that the programme is not suitable for everyone — including people with a history of eating disorders, those who have had an ileostomy or colostomy, and people undergoing chemotherapy.

ZOE's evidence base is genuinely stronger than most competitors. The METHOD randomised controlled trial, published in Nature Medicine in 2024, randomised 347 US adults aged 41–70 to either the personalised programme or standard dietary guidance for 18 weeks. Triglycerides fell significantly in the personalised group, though there was no significant between-group difference in LDL cholesterol, one of the two primary outcomes. Independent commentators have raised fair questions about how much of the benefit came from the microbiome personalisation specifically, versus the app engagement, coaching and the simple fact of eating more whole plant foods.

We cover this in far more depth in our dedicated ZOE gut health review.

Biomesight

Biomesight offers 16S rRNA sequencing at a lower price point — around $199 for an initial test with cheaper retests — and, importantly, lets you export your raw sequencing data. Turnaround is typically two to four weeks. For people who want the underlying data rather than a polished narrative, the raw-data export is a meaningful differentiator, because it means your money buys something portable rather than something locked inside an app.

Viome

Viome uses RNA sequencing and markets itself heavily on measuring microbial activity rather than composition, then sells custom-formulated supplements based on the result. The vertical integration between test and supplement sale is the thing to watch here: when the company interpreting your result also sells the recommended remedy, the incentive structure deserves scepticism.

Practitioner-Ordered Functional Stool Panels

Tests such as comprehensive digestive stool analyses are ordered through nutritional therapists, functional medicine practitioners and some private clinics. They typically bundle microbiome sequencing with markers like faecal calprotectin, secretory IgA, pancreatic elastase and occult blood. They generally cost several hundred pounds and are not available directly to consumers.

These panels are more informative than consumer kits because they include some genuinely validated markers alongside the microbiome data. The Lancet consensus panel specifically recommended that testing should be initiated by a clinician with a clear rationale, and that post-test therapeutic advice should come from the referring clinician rather than the testing company. That is a reasonable standard to hold any provider to.

Atlas Biomed: A Cautionary Tale Every UK Buyer Should Know

Atlas Biomed was, for years, one of the most visible UK microbiome and DNA testing companies. Then it simply disappeared. Its London office closed, its website went dark, its phone line stopped working, and customers found they could no longer access reports they had paid for — reports which, critically, were never downloadable in the first place.

The Information Commissioner's Office confirmed it had received complaints. Companies House records showed no accounts filed since December 2022, and BBC reporting identified that several remaining company officers were registered at an address in Moscow. Customers described paying £100 or more and losing access without warning, or paying for reports that never arrived and refunds that never came.

The lesson is not that all microbiome companies are unreliable. It is that you are handing biological data to a private company with no guarantee it will exist in five years, and that you should assume the report you receive is the only one you will ever get.

UK Test Comparison at a Glance

Are Gut Microbiome Tests Accurate? What the Evidence Says

This is the section that matters most, and it is the one most review articles skip.

The International Consensus Position

The 2025 consensus statement in The Lancet Gastroenterology & Hepatology is the most authoritative document currently available on this question. Its conclusions were direct: evidence supporting the clinical usefulness of microbiome testing is scarce; commercial providers are offering direct-to-consumer tests without regulatory consensus or proven clinical value; and this proliferation risks wasting both individual and healthcare resources.

The panel went further, recommending that patients and consumers should be discouraged from self-requesting microbiome testing, and that testing companies should not be the ones providing therapeutic advice off the back of their own results.

Analytical Validity: The Same Sample, Different Answers

Analytical validity asks a simple question — does the test accurately report what is actually in the sample? Independent research has found this cannot be assumed.

A study published in Communications Biology evaluated the analytical performance of direct-to-consumer gut microbiome testing services and found that variability between providers was on the same scale as biological variability between different people. In other words, the difference between two companies analysing your sample could be as large as the difference between your gut and a stranger's. The authors attributed this to methodological variability and insufficient quality control.

Reporting on related work, the American Gastroenterological Association described findings in which, for a set of 18 shared bacterial genera, no single method matched consensus values across all taxa, and on average only 10 to 16 of 18 taxa per company fell within the consensus range. Reproducibility within companies also varied — in one case, a replicate of the same sample produced a markedly different microbial profile, including more than 50% unidentified reads, and a consumer report was still issued.

"Dysbiosis" Is Not a Clinical Diagnosis

Almost every consumer report uses the word dysbiosis, and it is worth being blunt: there is no agreed clinical definition of dysbiosis and no validated reference range for microbial composition. Each company defines a "healthy" microbiome differently and compares you against different reference populations. Two companies can therefore legitimately call the same sample normal and abnormal.

Our article on what gut dysbiosis actually means unpacks this in more detail.

Ignore the Firmicutes-to-Bacteroidetes Ratio

If your report leads with a Firmicutes-to-Bacteroidetes ratio, treat it as a marketing metric rather than a health metric. The Lancet consensus specifically recommended that dysbiosis indices including this widely cited ratio, and phylum-level composition metrics generally, be excluded from clinical microbiome reports altogether.

Regulation Has Not Caught Up

Published analysis in the peer-reviewed literature has argued that the current regulatory framework leaves significant gaps, that DTC microbiome company websites are often misleading, and that the tests lack both analytical and clinical validity — meaning they may generate false positives and false negatives that consumers then act on. Gastroenterologists interviewed in that research consistently reported finding the results unhelpful, largely because companies do not publish the data needed to assess how their tests perform.

What a Gut Microbiome Test Can Usefully Tell You

Having made the case for scepticism, it would be dishonest to say these tests are worthless. There are three legitimate uses.

1. A Rough Sense of Diversity and Fibre-Fermenting Capacity

If your report shows very low diversity and low abundance of known fibre-fermenting, butyrate-producing organisms, that is a soft signal that your diet is probably low in plant variety. It is not a diagnosis, but it can be a useful prompt. The relevant intervention — eat more and more varied plants — is one you could adopt without testing, which is rather the point.

2. Tracking Your Own Trend Over Time

Because the biggest problem is variability between methods, comparing your result to someone else's is close to meaningless. Comparing your own result to your own earlier result, using the identical test and laboratory, is more defensible. If you retest after six months of a deliberate dietary change and see your diversity index rise, that trend carries more information than the absolute number ever did.

3. Behaviour Change and Engagement

This is underrated and slightly uncomfortable to admit. For some people, seeing their own data creates motivation that generic advice does not. If a £150 test is what finally gets someone eating lentils, oats and mixed vegetables consistently, the health return may be real — even if it came from the placebo of measurement rather than the measurement itself.

4. Raw Data for a Practitioner

If you are working with a registered dietitian, gastroenterologist or qualified nutrition professional, exportable raw sequencing data has more value than a proprietary app score. Ask before you buy whether the provider allows export.

What It Cannot Tell You (And the Red Flags to Watch)

Image: Bristol Stool Chart via Wikimedia Commons, CC BY-SA 3.0. See our full Bristol Stool Chart guide.

It Cannot Diagnose Disease

A consumer gut microbiome test cannot diagnose or exclude irritable bowel syndrome, Crohn's disease, ulcerative colitis, coeliac disease, microscopic colitis, bowel cancer, pancreatic insufficiency or bile acid malabsorption. If you have symptoms, a normal-looking microbiome report provides false reassurance, and that is the genuine harm — someone delaying a GP appointment because an app told them their gut score was 78 out of 100.

If you have persistent symptoms, read when to see a GP about stomach symptoms first.

It Cannot Confirm Leaky Gut, Candida or SIBO

Reports that claim to identify "leaky gut", intestinal permeability or candida overgrowth from a stool sequencing result are overreaching. Intestinal permeability is not measured by sequencing, and stool fungal signals do not reliably indicate clinical candidiasis. Small intestinal bacterial overgrowth occurs in the small bowel and is assessed by breath testing, not by faecal sequencing — a stool test physically samples the wrong compartment.

See our evidence reviews on whether leaky gut is real, candida overgrowth, SIBO and SIBO testing in the UK.

Red Flags in a Microbiome Report

• A named diagnosis derived purely from sequencing data
• A supplement protocol sold by the same company that ran the test
• A Firmicutes-to-Bacteroidetes ratio presented as a health score
• Claims about "leaky gut", candida or SIBO from a stool sample
• No disclosure of sequencing method or reference population
• No option to export or download your own data
• Advice to stop or change prescribed medication

Symptoms That Need a Doctor, Not a Test Kit

Please arrange an urgent GP appointment rather than buying a test if you have any of the following: blood in your stool or black tarry stools; unexplained weight loss; a persistent change in bowel habit lasting more than three weeks; a lump or mass in your abdomen; persistent vomiting; difficulty swallowing; unexplained iron-deficiency anaemia; or symptoms that wake you from sleep. These are red-flag features that require proper clinical assessment.

NHS and Validated Tests to Consider First

Here is the uncomfortable comparison. Several stool and blood tests with a robust evidence base are available through the NHS, free, where clinically indicated — and they answer questions a microbiome test cannot.

Faecal Immunochemical Test (FIT)

FIT detects invisible blood in stool and underpins the NHS Bowel Cancer Screening Programme. Everyone aged 50 to 74 registered with a GP in England is now automatically sent a home kit every two years, following the completion of the age extension announced by NHS England; people aged 75 and over can request one. It is also used to triage symptomatic patients. This is a genuinely validated, guideline-supported test — and it costs you nothing.

More detail in our guide to bowel cancer screening in the UK.

Faecal Calprotectin

Faecal calprotectin measures intestinal inflammation and is one of the most clinically useful non-invasive markers in gastroenterology. NICE recommends it as an option to help distinguish inflammatory bowel disease from IBS in adults with recent-onset lower gastrointestinal symptoms where specialist assessment is being considered, provided cancer is not suspected. It has done more to spare people unnecessary colonoscopies than any microbiome panel ever will.

See our explainer on the calprotectin test in the UK.

Coeliac Serology

Coeliac disease is diagnosed with blood tests for tissue transglutaminase antibodies, usually followed by biopsy — and crucially, you must still be eating gluten for the test to be valid. No microbiome test can diagnose coeliac disease. Read coeliac testing in the UK and coeliac vs gluten intolerance.

Helicobacter pylori Testing

Upper gastrointestinal symptoms are often driven by H. pylori, diagnosed by urea breath test or stool antigen test and treated with eradication therapy. See our guides to H. pylori testing and H. pylori infection.

Blood Tests

Full blood count, ferritin, B12, folate, CRP, coeliac serology, liver and thyroid function will identify more clinically actionable problems in a symptomatic person than any sequencing panel. Our gut health blood test guide covers what to ask for.

Validated vs Consumer Testing

Our broader UK stool testing guide compares these in more detail, and our food intolerance test review and zonulin test review apply the same lens to two other popular consumer tests.

Cost vs Value: The Money Question

Who Might Reasonably Benefit

• People who have already had appropriate clinical investigation, have no red flags, and are curious about their own biology
• Self-quantifiers who will genuinely retest and track a trend using the same laboratory
• People working with a qualified practitioner who has asked for raw data
• Those who know that structured feedback is what makes them stick to a dietary change

Who Should Skip It

• Anyone with new, changing or red-flag symptoms — see a GP
• Anyone hoping to rule out a disease
• Anyone on a tight budget who would be better spending it on food
• Anyone with a history of disordered eating, for whom food-scoring apps can be actively harmful
• Anyone expecting the report to tell them which supplement to buy

What £200 Buys Instead

It is worth stating plainly: £200 buys roughly six months of a high-quality multi-strain probiotic, or around forty weeks of the additional legumes, nuts, seeds and vegetables it would take to move from ten plant varieties a week to thirty. The evidence that plant diversity shifts the microbiome is considerably stronger than the evidence that knowing your microbiome shifts your health.

Data Privacy: Who Owns Your Microbiome Data?

The Atlas Biomed episode should be required reading for anyone about to post a biological sample to a private company. Before you buy, get answers to these questions in writing:

• Can I download my raw data, and in what format?
• Where is my data stored, and under which jurisdiction?
• Is my sample destroyed after analysis, or biobanked?
• Is my data shared with or sold to third parties, including for research?
• What happens to my data if the company is acquired or ceases trading?
• How do I request deletion under UK GDPR?

A company that cannot answer these clearly is not a company you should send a stool sample to. Use a separate email address, share the minimum personal information required, and download and save your results the day you receive them.

How to Choose a Gut Microbiome Test in the UK

If you have read this far and still want to test, here is a sensible checklist.

1. Confirm the sequencing method. If a company will not tell you whether it uses 16S or shotgun metagenomics, walk away.
2. Check for raw data export. This is the difference between owning your data and renting a dashboard.
3. Look for independent validation. Peer-reviewed publications involving the actual product, not general microbiome science.
4. Check the reference population. Being compared against a US cohort when you live in the UK matters more than it sounds.
5. Watch the supplement tie-in. Separate the diagnostic from the shop wherever possible.
6. Verify the company exists properly. Companies House filings, a UK address, a working phone number, recent accounts.
7. Check clinical exclusions. Pregnancy, IBD, ostomies, chemotherapy and eating disorder history are common contraindications.
8. Plan the retest before the first test. A single snapshot is close to useless. Budget for two.

What to Actually Do With Your Results

Image: assorted whole foods via Wikimedia Commons, public domain.

Here is the slightly deflating truth: whatever your report says, the evidence-based next steps are broadly the same for almost everyone.

Increase Plant Diversity Before Anything Else

The American Gut Project — the largest citizen-science microbiome study of its kind, with a UK arm known as the British Gut Project — found that participants who ate more than 30 different plant types per week had more diverse gut microbiomes than those eating ten or fewer. Notably, plant variety predicted diversity better than diet labels like "vegan" or "vegetarian" did.

Thirty is a target, not a threshold. Herbs, spices, nuts, seeds, wholegrains and pulses all count. Start with our 30 plants a week guide, how to increase fibre safely and our list of high-fibre foods in the UK.

Add Fermented Foods

Fermented foods are a low-cost, low-risk addition with reasonable supporting evidence. See fermented foods in the UK, kefir benefits and our comparison of fermented foods vs probiotic supplements.

Feed What You Already Have

Prebiotic fibres and polyphenols support the microbes already present, which is usually more productive than trying to introduce new ones. Explore prebiotic foods, polyphenols and gut health, the best prebiotic supplements and the difference between prebiotics and probiotics.

Use Supplements Deliberately, Not Reflexively

If a report flags low butyrate-producing capacity, the sensible response is more fermentable fibre; a butyrate supplement is a secondary consideration. If Akkermansia is low, understand that Akkermansia differs from conventional probiotics before buying. And whatever the report says, review the general evidence in do probiotics actually work and our roundup of the best probiotics in the UK.

A Sensible 12-Week Plan

How to Improve Your Gut Without Testing at All

If you take one thing from this article, take this: nothing in the list below requires a test result.

• Eat 30 different plant foods across a week
• Aim for the UK recommendation of around 30g of fibre daily, increasing gradually
• Include fermented foods most days
• Minimise ultra-processed foods — see ultra-processed food and the gut
• Protect sleep and manage stress; see the gut-brain connection
• Move regularly — physical activity is independently associated with microbial diversity
• Use antibiotics only when indicated, and consider probiotics after antibiotics
• Track your stool type using the Bristol Stool Chart — free, and more useful day to day than any sequencing report

If you have diagnosed IBS, a structured approach is likely to help more than testing: see IBS types, the low FODMAP diet and supplements for IBS.

Our Final Verdict

Verdict: 5/10 for most people. Interesting, not diagnostic, and rarely worth the price as a one-off purchase.

A gut microbiome test in the UK in 2026 is a well-marketed snapshot of a moving ecosystem, produced by an industry that has outpaced both its evidence base and its regulation. The international consensus is that these tests are not ready for clinical use, independent analysis shows providers disagree with one another to a degree that undermines confidence in any single result, and the central concept most reports are built on — dysbiosis — has no agreed definition.

If you are symptomatic, see your GP and use the validated tests the NHS already offers. If you are asymptomatic and curious, understand exactly what you are buying: a data point, not a diagnosis. And if you simply want a better gut, the interventions that work are available to you today, at the supermarket, without sequencing anything.

Explore the Welzo gut health collection and our probiotics range, or start with the fundamentals in our UK gut health guide and best foods for gut health.

Frequently Asked Questions

Are gut microbiome tests worth it in the UK?

For most people, no. A gut microbiome test cannot diagnose any condition, and independent research has shown that different providers analysing the same sample can return substantially different results. The 2025 international consensus in The Lancet Gastroenterology & Hepatology found insufficient evidence to recommend routine microbiome testing and discouraged consumers from self-requesting it. They can have value as a motivational tool or for tracking your own trend over time with the same laboratory, but they are not a substitute for clinical assessment.

How much does a gut microbiome test cost in the UK?

Consumer tests typically range from about £100 to £400. ZOE's kit was listed at around £149 plus an app membership of roughly £10 per month as of April 2026, while Biomesight sits at a similar price point with cheaper retests. Practitioner-ordered functional stool panels usually cost several hundred pounds and are not sold directly to consumers. NHS tests such as FIT and faecal calprotectin are free where clinically indicated.

Can a gut microbiome test diagnose IBS, IBD or bowel cancer?

No. None of these conditions can be diagnosed or excluded from a consumer stool sequencing test. IBS is a clinical diagnosis, IBD requires markers such as faecal calprotectin followed by endoscopy, and bowel cancer screening uses the faecal immunochemical test with colonoscopy where indicated. Relying on a normal microbiome report while you have symptoms risks dangerous delay.

Which is the most accurate gut microbiome test in the UK?

Shotgun metagenomic sequencing offers higher resolution than 16S rRNA sequencing, so tests using it can identify organisms to species level rather than genus level. However, higher resolution does not equal clinical accuracy. Research published in Communications Biology found that variability between commercial providers was comparable to biological variability between different people, so no UK test can currently be described as definitively accurate.

Can a gut microbiome test detect SIBO or leaky gut?

No. SIBO occurs in the small intestine and is assessed using hydrogen and methane breath testing; a stool sample reflects the large intestine, so it samples the wrong part of the gut. Intestinal permeability, often called leaky gut, is not measured by DNA sequencing at all. Any report claiming to identify either from stool sequencing is overstating what the technology can do.

How often should you take a gut microbiome test?

If you choose to test at all, a single result has limited value because your microbiome changes with diet, travel, illness, medication and stress. If you are tracking a deliberate intervention, retesting after around three to six months with the identical test and laboratory is more informative. Comparing results across different providers is not meaningful.

Does the NHS offer gut microbiome testing?

No. The NHS does not offer microbiome sequencing because it is not a validated diagnostic test. The NHS does offer validated stool and blood tests where clinically indicated, including the faecal immunochemical test used in bowel cancer screening for those aged 50 to 74, faecal calprotectin to help distinguish IBD from IBS, coeliac serology and H. pylori testing.

Is ZOE worth it compared with a standard microbiome test?

ZOE has the strongest published evidence of the consumer options, including a randomised controlled trial in Nature Medicine in 2024 which found significant triglyceride reduction but no significant between-group difference in LDL cholesterol. Since September 2025 the programme no longer includes the continuous glucose monitor or blood fat test. What you are largely paying for is a structured, app-delivered dietary coaching programme; whether that is worth the ongoing subscription depends on whether app-based coaching works for you.

What should I do if my gut microbiome test says I have dysbiosis?

Treat it as a prompt rather than a diagnosis. There is no agreed clinical definition of dysbiosis and no validated reference range, so different companies apply different thresholds to the same data. The sensible response is to increase plant variety and fibre gradually, include fermented foods, and see your GP if you have symptoms. Avoid buying a supplement protocol from the same company that produced the report.

Is my data safe if I take a gut microbiome test?

Not automatically. In 2024 and 2025, UK company Atlas Biomed ceased operating without notice, leaving customers unable to access reports they had paid for and unsure what had happened to their data; the Information Commissioner's Office confirmed it had received complaints. Before ordering, confirm in writing that you can download your raw data, where it is stored, whether samples are destroyed after analysis, and how to request deletion under UK GDPR.

References

1. Porcari S, et al. International consensus statement on microbiome testing in clinical practice. The Lancet Gastroenterology & Hepatology. 2025;10(2):154–167. View study
2. Evaluating the analytical performance of direct-to-consumer gut microbiome testing services. Communications Biology. 2026. View study
3. American Gastroenterological Association. Direct-to-consumer microbiome tests prove wide variability. AGA News. April 2026. Read article
4. Gut Microbiota for Health. New international consensus on microbiome testing in clinical practice. Read summary
5. Is the current regulatory framework for direct-to-consumer microbiome-based tests sufficient to protect consumers? PMC. View paper
6. Bermingham KM, et al. Effects of a personalized nutrition program on cardiometabolic health: a randomized controlled trial. Nature Medicine. 2024;30:1888–1897. View study
7. McDonald D, et al. American Gut: an Open Platform for Citizen Science Microbiome Research. mSystems. 2018;3(3):e00031-18. View study
8. National Institute for Health and Care Excellence. Faecal calprotectin diagnostic tests for inflammatory diseases of the bowel (DG11). View guidance
9. NHS. Bowel cancer screening. View page
10. NHS England. NHS rolls out lifesaving home testing for bowel cancer to over 50s. Read announcement
11. Cancer Research UK. NHS England increasing bowel cancer screening sensitivity. January 2026. Read article
12. Which? ZOE app review: is it worth it? April 2026. Read review
13. Progress Educational Trust. DNA testing company vanishes, as does customers' data. Read article
14. The Microsetta Initiative, UC San Diego. 30 plants per week: why eating more fruits and vegetables matters for your gut microbiome. Read article
15. International Scientific Association for Probiotics and Prebiotics. Visit ISAPP

About the Author

This article was written and medically reviewed by Dr Zeeshan Afzal, Medical Officer at Welzo. Dr Afzal reviews Welzo's digestive health content for clinical accuracy and alignment with current UK guidance. Content is reviewed and updated as new evidence emerges.

Medical Disclaimer

This article is provided for general information and education only. It is not medical advice, is not a substitute for consultation with a qualified healthcare professional, and should not be used to diagnose or treat any condition. Do not delay seeking medical advice because of anything you have read here. If you have persistent digestive symptoms, blood in your stool, unexplained weight loss or any other red-flag symptom, contact your GP or call NHS 111. In an emergency, call 999. Always speak to your GP or pharmacist before starting any new supplement, particularly if you are pregnant, breastfeeding, taking prescribed medication or living with a diagnosed condition.