A Practical Guide to Microbiome Testing in the UK

The UK market for commercial microbiome testing has grown significantly, with several companies now offering direct-to-consumer gut analysis. This guide compares the main options, explains what each tests, and helps you decide whether testing is right for you.

The Main UK Tests

Zoe (£299)

What it tests: Gut microbiome (shotgun metagenomics), blood sugar responses (CGM), blood fat responses Method: Stool sample + 2-week continuous glucose monitor + finger-prick blood tests What you get: Personalised food scores (0–100), diversity metrics, specific bacterial species identified, ongoing app membership

Zoe is the most comprehensive option, combining microbiome data with metabolic testing to generate personalised dietary recommendations. It is backed by the PREDICT studies from King's College London. For a detailed assessment, see our Zoe review.

Best for: People who want the most complete picture and are willing to pay for it

Atlas Biomed (£149)

What it tests: Gut microbiome (16S rRNA sequencing), with optional DNA health test (separate purchase) Method: Stool sample sent by post What you get: Microbiome diversity score, bacterial composition breakdown, fibre metabolism assessment, vitamin synthesis potential, probiotic recommendations, disease protection scores

Atlas Biomed uses 16S rRNA sequencing, which is less detailed than Zoe's shotgun metagenomics but significantly cheaper. The reports are visually polished and include actionable dietary recommendations. They also provide a personalised food list based on your results.

Best for: Budget-conscious consumers who want a solid microbiome overview without the metabolic testing

Thriva (£49–£99 for gut health panels)

What it tests: Primarily blood biomarkers related to gut health (inflammation markers, vitamin deficiencies, coeliac screening). Thriva does not offer full microbiome sequencing. Method: Finger-prick blood test sent by post What you get: GP-reviewed results for inflammation markers (CRP), vitamin D, iron, B12, folate, coeliac antibodies

Thriva is not a microbiome test in the traditional sense — it measures blood markers that can indicate gut health problems. It is clinically useful for screening specific conditions but does not tell you about your bacterial composition.

Best for: People with symptoms who want a clinical screening before (or instead of) microbiome testing

Other Options

Ombre (formerly Thryve) — US-based but ships to the UK. Uses 16S rRNA sequencing. Around £120. Less UK-specific in its recommendations.

Viome — US-based, uses metatranscriptomics (measures which genes are active, not just present). Around £150. Interesting technology but limited UK-specific guidance.

MyMicroZoo — Research-grade analysis used by some UK functional medicine practitioners. Not direct-to-consumer.

What Each Method Tells You

| Feature | 16S rRNA (Atlas) | Shotgun Metagenomics (Zoe) | Blood Markers (Thriva) | |---|---|---|---| | Bacterial identification | Genus level | Species/strain level | N/A | | Fungi and viruses | No | Yes | N/A | | Functional analysis | Limited | Yes | N/A | | Diversity metrics | Yes | Yes | N/A | | Reproducibility | Moderate | Higher | High (clinical standard) | | Clinical validity | Low | Low-moderate | High (validated assays) | | Cost | £149 | £299 | £49–99 |

How to Interpret Results

Microbiome test results typically include:

Diversity scores — Higher is generally better. If your alpha diversity is low, increasing dietary fibre and plant variety is the most evidence-based intervention. See our guide to fibre and the microbiome.

Bacterial composition — Most tests show the relative abundance of major bacterial groups. Look for the Firmicutes-to-Bacteroidetes ratio (though its clinical significance is debated), the presence of beneficial species like Faecalibacterium prausnitzii and Akkermansia, and any flagged overgrowths.

Dietary recommendations — Take these as general guidance, not prescriptions. Most recommendations boil down to: eat more fibre, eat more diverse plants, include fermented foods, and reduce ultra-processed food — which is sound advice for almost everyone.

"Risk scores" — Some tests assign risk scores for conditions like diabetes or inflammatory bowel disease. Treat these with extreme caution. No commercial microbiome test can diagnose or reliably predict disease. These scores are based on population-level associations, not validated diagnostic criteria.

When Testing Is Useful

• Tracking changes over time — A single test is a snapshot. Testing before and after a significant dietary change (e.g., increasing fibre intake or following the Mediterranean diet for three months) can show whether your intervention has shifted your microbiome
• Curiosity and motivation — For some people, seeing their own data provides motivation to improve their diet. If a £149 test gets you to eat 30g of fibre daily, it has paid for itself
• Research participation — Tests like Zoe contribute to ongoing research, and some participants value being part of the science

When Testing Is Unnecessary

• If you have clear symptoms — See your GP first. Digestive symptoms like persistent bloating, changed bowel habits, or blood in the stool need clinical investigation, not a commercial microbiome test. Your GP can arrange validated tests for coeliac disease, inflammatory bowel disease, and other conditions through the NHS
• If your budget is limited — The money spent on a test would be better spent on the dietary changes that every test would recommend anyway: more vegetables, fruits, wholegrains, legumes, and fermented foods
• If you expect a diagnosis — No commercial test can tell you what is wrong. They can indicate general patterns that may warrant further investigation

A GP's Perspective

Most NHS GPs are cautious about commercial microbiome tests. The general consensus in clinical practice is that these tests can provide interesting information but have limited clinical utility at present. If your results concern you, bring them to your GP — but be aware that your GP may not be trained in interpreting microbiome sequencing data and may recommend standard clinical tests instead.

For a deeper look at the accuracy and limitations of these tests, see our article on microbiome test accuracy.

Key Takeaways

• Zoe offers the most comprehensive testing (microbiome + metabolic) but at the highest price (£299)
• Atlas Biomed provides a solid microbiome overview at a mid-range price (£149) using 16S rRNA sequencing
• Thriva is best for clinical blood marker screening, not microbiome analysis
• No commercial test can diagnose disease or replace clinical investigation
• For most people, spending the test budget on dietary improvement would deliver greater health benefits
• If you do test, consider retesting after 3–6 months of dietary changes to track progress