Key Insights

• See whether any single microbe is crowding out others in your gut, which can explain symptoms and signal where balance needs restoring.
• Spot microbial overgrowth patterns that may relate to bloating, gas, irregularity, food sensitivities, or low-grade inflammation.
• Clarify how antibiotics, low-fiber eating, stress, or recent illnesses may have shifted your gut community toward a few “dominant” species.
• Support targeted nutrition, prebiotic, or probiotic discussions with your clinician or dietitian based on which species are overrepresented.
• Track whether dominance resolves over time as you and your care team adjust diet, medications, or routines.
• If appropriate, integrate overabundance findings with other panels (e.g., stool inflammation, metabolic, or immune markers) for a more complete picture.

What is an Overabundant Species Test?

The overabundant species test pinpoints bacterial and fungal groups with unusually high relative abundance. Results highlight “who’s too loud in the room,” flagging species or genera that dominate beyond typical reference ranges for a healthy, diverse gut community. Because microbiomes evolve with diet, medications, and stress, this test reflects your current ecosystem rather than a fixed trait.

Why this matters: your gut microbes help digest fiber into short-chain fatty acids, shape immune tone, train the gut barrier, and even influence metabolic and mood signaling through the gut–brain axis. When one or a few taxa swell beyond their neighbors, functions can skew — think excess gas production, altered bile acid recycling, or more inflammatory signaling. While the science continues to mature, consistent patterns emerge: more diversity is generally linked with resilience, and dominance by a narrow cast of microbes often tracks with symptoms or instability.

Why Is It Important to Test For Overabundant Species?

Day to day, your microbiome is like a city that runs on shared jobs. Different microbial “neighborhoods” ferment fiber, produce vitamins, reinforce the mucus barrier, and break down bile. When one group grows outsized, it can crowd out helpful neighbors and tilt the city’s economy. The overabundant species test connects that biology to real-life questions: Why the sudden bloating after antibiotics? Could your recent ultra-processed stretch be feeding gas-producing microbes? Are you seeing more skin flares or food-triggered discomfort after a restrictive diet? By mapping relative abundance against reference populations, the test helps identify dysbiosis patterns that can accompany digestive symptoms, immune reactivity, and metabolic shifts.

It’s particularly useful after big inflection points — a course of antibiotics, a major diet change, new supplements, travel, a GI infection, or persistent symptoms that haven’t resolved. Overabundance of certain pathobionts (microbes that can be friendly in moderation but problematic in excess) may point to lower short-chain fatty acid output, higher histamine or lipopolysaccharide exposure, or reduced butyrate producers that support the gut barrier. For context, larger cohort studies associate higher microbial diversity with metabolic flexibility and lower inflammatory tone, though specifics vary and ongoing research is refining the details. This test won’t diagnose disease and it won’t locate small-intestinal overgrowth directly (stool reflects the colon, and breath testing assesses the small intestine). It’s a snapshot, based on relative — not absolute — counts, and results can differ across labs because of sequencing methods and databases. Used alongside your history and other biomarkers, it becomes a practical compass rather than a verdict.

What Insights Will I Get From a Overabundant Species Test?

Your report shows which species or genera are disproportionately high compared with reference ranges. It typically summarizes relative abundance, diversity metrics, and functional clues — for example, whether gas producers or mucin degraders occupy more space than is typical for a stable gut community. “Balanced” profiles tend to feature higher diversity and healthy representation of beneficial genera like Bifidobacterium and Faecalibacterium.

When the ecosystem is balanced, you’re more likely to see efficient fiber fermentation with robust short-chain fatty acid production (butyrate, acetate, propionate), steadier immune signaling, and a well-supported gut barrier. Optimal patterns vary by person, geography, and diet, but stability and diversity are the recurring themes.

When imbalance appears, you may see lower diversity with one or a few taxa dominating. That pattern can align with symptoms such as gas, urgency, constipation, or food-triggered discomfort, or with an ecosystem recovering from antibiotics or infection. These findings aren’t a diagnosis — they’re functional signposts that can inform nutrition strategies, prebiotic discussions, or medical evaluation if symptoms persist.

Big picture, this test is most informative when viewed over time and alongside other markers such as fecal calprotectin (gut inflammation), serum metabolic labs, or immune panels. Keep in mind that recent antibiotics, colonoscopy prep, probiotics, and acute illness can shift results; collection variability and lab methods also influence readouts. Interpreted in context, the overabundant species test helps personalize your path toward steadier digestion, energy, and resilience.