What is a gut microbiome test?

A gut microbiome test analyzes a small stool sample to identify which microorganisms live in your digestive tract and, in some cases, what those microbes are actively doing. Results are typically returned as a report of microbial activity along with food and supplement recommendations based on that profile.

What is the difference between DNA and RNA microbiome testing?

DNA sequencing (16S rRNA or shotgun metagenomics) identifies which organisms are present. RNA sequencing (metatranscriptomics) measures gene expression — what those organisms are actively producing right now. DNA answers who is there; RNA answers what they are doing, which is what determines the metabolites your body actually encounters.

Are at-home gut microbiome tests accurate?

Accuracy varies widely by method. Sequencing technology itself is well established, but tests differ in resolution (species vs. strain level), whether they measure activity or only presence, and how recommendations are generated. Look for published methodology, a CLIA-certified lab, and specificity about what the test can and cannot tell you.

How much does a gut microbiome test cost?

At-home microbiome tests generally range from about $100 for basic presence-only panels to roughly $300 for tests that include RNA-level analysis and personalized nutrition recommendations. Some include supplement subscriptions, which is a separate ongoing cost worth checking before purchase.

Can a microbiome test tell me which foods are best for me?

Tests that analyze microbial activity can generate personalized food recommendations, because the same food can be metabolized differently depending on which microbes are active in your gut. Research on personalized nutrition supports the idea that individual responses to identical meals vary substantially between people.

Gut Microbiome Testing: What It Is and How It Works

Why generic food advice stops working

Most nutrition guidance is written for a population average. It is a reasonable starting point — eat more plants, more fiber, less ultra-processed food — and for many people it is enough. But if you've done everything “right” and still feel unpredictable after meals, the average may simply not describe you.

One reason is your gut microbiome: the trillions of bacteria, viruses, and fungi in your digestive tract. These microbes break down what you eat into compounds your body absorbs. Because two people host different microbial communities, the same oatmeal can yield a different mix of end products in each of them. Research on personalized nutrition has found that individual responses to identical meals vary substantially from person to person.

What a gut microbiome test measures

You collect a small stool sample at home, mail it to a lab, and the lab sequences the genetic material in it. What happens next depends on the method, and the distinction matters more than the marketing usually admits:

Method	What it sequences	What you learn
16S rRNA (DNA)	One marker gene	Rough composition, usually to genus level. Cheapest; least specific.
Shotgun metagenomics (DNA)	All DNA present	Which organisms are present, often to species or strain level.
Metatranscriptomics (RNA)	Actively expressed genes	What the microbes are actively producing — activity, not just presence.

The DNA-versus-RNA difference is the one to understand before you buy. DNA tells you who is in the room. RNA tells you what they are doing. Since it is microbial activity that produces the metabolites your body encounters, activity data is what food recommendations can meaningfully be built on.

How to evaluate a test before buying

Is the methodology published? Credible companies describe their sequencing approach and cite peer-reviewed work.
Is the lab CLIA-certified? This is a baseline quality standard for lab operations.
Do results agree between companies?Often they don't — see our review of the accuracy research.
Does it measure activity or only presence? See the table above.
What do you actually get back? A list of bacteria names is interesting; specific, ranked food guidance is actionable.
What does it cost over time? Check whether the price includes a supplement subscription and what the minimum commitment is.
What does it claim? A general wellness test provides insights to inform your choices. Be skeptical of anything promising a medical diagnosis or a fix for a specific condition — that is not what these tests are for.

What testing can't do

A microbiome test is not a diagnostic tool. It will not identify disease, and it is not a substitute for talking to a clinician about symptoms that concern you. It also isn't a shortcut around the fundamentals: sleep, movement, stress, and consistency still do most of the work. Testing narrows the guesswork about which foods to prioritize — it doesn't replace the habit of eating well, which is the harder part and the reason this site exists.

Where Viome fits

Habit is made by the team at Viome, so treat this section as what it is: us describing our own product. Viome's Gut Intelligence and Full Body Intelligence tests use RNA sequencing (metatranscriptomics) to analyze microbial activity, then translate the results into personalized food recommendations — foods to prioritize, foods to minimize — along with scores for aspects of digestive wellness. They are general wellness tests: they provide insights and recommendations to inform healthy eating habits, which, as part of a healthy lifestyle, may help support your long-term health.

The rest of this site stays free and useful whether or not you ever buy anything from us. That's the deal, and our editorial policy spells it out.

This page is for informational purposes and is not medical advice. Viome Intelligence Tests are general wellness tests and are not intended to diagnose, treat, cure, or prevent any disease. Talk to a healthcare provider about symptoms or conditions that concern you.