Short answer: "neurobiome testing" means using a gut microbiome test to read the gut–brain layer of your microbiome — the community of gut bacteria that help make and modulate brain-relevant signals like serotonin and GABA and communicate with the brain along the gut–brain axis. It is a lens for understanding and personalizing everyday support — a wellness insight, not a medical diagnosis of anxiety, depression, ADHD, or autism. Below is how a gut microbiome test actually works, what the gut–brain science genuinely shows (and what it does not), and how a test turns into a formula matched to you.
What is neurobiome testing?
If you have ever felt like your gut and your head are somehow talking to each other, you are not imagining it — and it is fair to want to see what is actually going on. "Neurobiome" is the name Flore uses for the gut-microbiome community as it relates to the brain: the microbes and microbial signals that participate in the gut–brain conversation. Neurobiome testing simply means looking at your gut microbiome through that gut–brain lens. It rests on an established idea in the science — the gut–brain axis — which one widely cited review defines as "bidirectional communication between the central and the enteric nervous system, linking emotional and cognitive centers of the brain with peripheral intestinal functions." A test reads the microbial side of that conversation. For the concept itself, start with what the neurobiome is and the gut–brain axis explained. To be clear up front: neurobiome and neurobiotics are framing terms Flore is pioneering on top of the established gut–brain and psychobiotics science — they are not themselves a separate, peer-reviewed diagnostic category.
How does a gut microbiome test actually work?
A microbiome test starts with a small stool sample, because that is where the gut community can be sampled non-invasively. The NIH's National Human Genome Research Institute defines the microbiome as "the community of microorganisms (such as fungi, bacteria and viruses) that exists in a particular environment." To see who is in yours, a lab reads the DNA in the sample. There are two main sequencing approaches, and the difference matters:
- 16S rRNA gene sequencing. This reads a single bacterial marker gene. As one methods paper puts it, inferences are made "by sequencing PCR amplicons from the ribosomal 16S RNA gene," a domain "restricted to bacteria and archaea." It is efficient and good for surveying many samples, but "offers limited taxonomical and functional resolution."
- Shotgun metagenomic sequencing. Here "whole-metagenome shotgun analyses are accomplished by unrestricted sequencing of the genome of all microorganisms present in a sample." Crucially, it "provides a direct assessment of the functional attributes of the microbiome" — not just who is there but what they can do, including "the discovery of new bacterial genes and genomes."
That functional layer is the part a gut–brain reading cares about, because the gut–brain story is largely about function: which microbes can produce or influence neuroactive signals.
What can the gut-brain layer actually tell us?
This is where honesty matters, because the gut–brain field is full of overreach. What is well supported:
- The gut is a major site of serotonin. A review from Emeran Mayer's group reports that of the body's serotonin (5-HT), "95% of the body's 5-HT stored in ECCs and enteric neurons, and only 5% stored in the CNS" — ECCs being the enterochromaffin cells lining the gut. See where the gut makes serotonin.
- Gut bacteria produce neuroactive substances. A psychobiotics review from the Dinan and Cryan groups notes that "gut bacteria also produce a range of neurotransmitters," including "GABA by the Bifidobacteria family" and "GABA and acetylcholine by the Lactobacilli family." See does the gut produce GABA.
- There are real channels back to the brain. Communication "involves the vagus nerve, which transmits information from the luminal environment to CNS," and microbial short-chain fatty acids (SCFAs) are "able to stimulate sympathetic nervous system, mucosal serotonin release." SCFAs from certain gut bacteria "regulate a significant percentage of ECC 5-HT synthesis and release." See the vagus nerve and how Lactobacillus talks to your brain.
So a neurobiome reading can show whether your sample carries microbes and functions associated with these gut–brain signals, and how diverse your community is. What it cannot do is read your mood off a stool sample.
What neurobiome testing is NOT
A microbiome test is a wellness insight into your gut ecosystem — it is not a medical diagnosis. It does not diagnose, and cannot rule in or out, anxiety, depression, ADHD, autism, or any other condition. The gut–brain links above are associations and mechanisms studied at the group level; they do not translate into a personal verdict about your mental health. Anyone selling a microbiome test as a diagnosis of a mental-health condition is overstepping the science. If you are struggling with mood, anxiety, focus, or sleep, a qualified clinician — not a stool test — is the right starting point. Think of neurobiome testing as information that helps you make a more targeted decision about everyday gut support, not a prediction about an outcome.
From test to matched support: psychobiotics and neurobiotics
The reason to read the gut–brain layer is to act on it more precisely. The scientific lineage here is "psychobiotics," defined in the literature as "live bacteria (probiotics) which, when ingested, confer mental health benefits through interactions with commensal gut bacteria" — a definition later expanded to include prebiotics that feed those bacteria. Flore uses neurobiotics as the everyday, forward-looking term for this same idea: strains and prebiotics chosen to support the gut–brain layer. For the background, see psychobiotics and the gut–brain axis and how gut health affects mental health. None of this is a claim that a probiotic treats or cures a condition — it is structure/function support: feeding and populating a gut community that participates in these signals.
Where Flore fits
Flore (formerly Sun Genomics) is built around exactly this test-then-match idea. A gut microbiome test is the front door; from your results, Flore builds a formula from what is actually in your gut — up to 68 curated strains plus 40+ prebiotics, matched to you rather than sold as a one-size-fits-all blend, and refined against more than 40,000 formulations of experience. The microbial layer of that gut–brain conversation is what Flore calls the neurobiome, used as a personalization lens — not a claim that any product is a proven brain treatment. If you would rather start simple, GoodOnes™ single-strain synbiotics let you begin with one aim: The Calm One (SETTLE) for everyday focus and calm, or The Bright One (MOOD) for everyday mood support. Either way, the point is the same: a test turns a guess into a decision you can feel confident about.
These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease. This article is educational and is not medical advice; if anxiety, low mood, focus, or sleep is persistent or affecting your daily life, please talk to a qualified healthcare provider.
Sources
- Carabotti M, Scirocco A, Maselli MA, Severi C. The gut-brain axis: interactions between enteric microbiota, central and enteric nervous systems. Annals of Gastroenterology. 2015;28(2):203-209. pmc.ncbi.nlm.nih.gov
- Martin CR, Osadchiy V, Kalani A, Mayer EA. The Brain-Gut-Microbiome Axis. Cellular and Molecular Gastroenterology and Hepatology. 2018;6(2):133-148. pmc.ncbi.nlm.nih.gov
- Sarkar A, Lehto SM, Harty S, Dinan TG, Cryan JF, Burnet PWJ. Psychobiotics and the Manipulation of Bacteria-Gut-Brain Signals. Trends in Neurosciences. 2016;39(11):763-781. pmc.ncbi.nlm.nih.gov
- Jovel J, Patterson J, Wang W, et al. Characterization of the Gut Microbiome Using 16S or Shotgun Metagenomics. Frontiers in Microbiology. 2016;7:459. pmc.ncbi.nlm.nih.gov
- Appleton J. The Gut-Brain Axis: Influence of Microbiota on Mood and Mental Health. Integrative Medicine (Encinitas). 2018;17(4):28-32. pmc.ncbi.nlm.nih.gov
- National Human Genome Research Institute (NIH). Microbiome — Talking Glossary of Genomic and Genetic Terms. genome.gov
Curious what your own gut-brain picture looks like?
A gut microbiome test is the front door. Flore (formerly Sun Genomics) sequences your gut and builds a formula from what is actually there — up to 68 curated strains plus 40+ prebiotics, matched to your own results.
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Want a simpler, single-strain place to start? The Calm One (SETTLE) is a GoodOnes™ synbiotic for everyday focus and calm, and The Bright One (MOOD) for everyday mood support — each $49 (Subscribe & Save $44.10).
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