# Beyond Diversity: Why InnerBuddies Tests for What Your Microbiome Does—Not Just What’s There Understanding the gut microbiome requires more than cataloguing which species are present. A functional perspective — measuring what microbes produce and which metabolic pathways they run — provides a clearer view of how the microbiome influences digestion, inflammation, nutrient absorption, and systemic health. InnerBuddies emphasizes a microbiome function test to capture this activity-based picture rather than relying solely on taxonomic diversity. ## Looking beyond composition to function Taxonomic tests identify species and relative abundance. Those data are useful, but they can miss important differences in microbial behavior. Two people can show similar diversity measures while exhibiting very different metabolic outputs. Functional testing examines microbiome metabolic pathways and the metabolites produced, revealing how bacteria process dietary components, synthesize vitamins, or generate signaling molecules that affect the host. ## Why microbiome activity matters Microbial activity determines impact. For example, short-chain fatty acids (SCFAs) such as butyrate arise from fermentation of fiber and support colonocyte health, intestinal barrier integrity, and local immune regulation. Conversely, production of potentially harmful metabolites (e.g., certain phenolic compounds or excess hydrogen sulfide) can correlate with symptoms or disrupted gut function in some contexts. Measuring metabolic output and pathway expression gives a more actionable picture of whether an ecosystem is functioning in a health-promoting way. ## Mapping bacterial pathways Functional tests map enzymatic and metabolic pathways — fermentation routes, bile acid transformations, vitamin biosynthesis, and xenobiotic metabolism. These maps reveal which processes are active and at what relative levels. Knowing that a subject’s microbiome is low in butyrate-producing pathway activity, for instance, suggests different interventions than simply noting low abundance of a particular genus. Assessing pathway-level activity aligns microbial data with biochemical functions relevant to host physiology. ## Personalization grounded in activity When microbiome testing focuses on function, recommendations can be tailored to measured deficits or imbalances in metabolic output rather than driven only by compositional markers. For example, low production of anti-inflammatory metabolites may prompt dietary strategies to increase fermentable fiber and support SCFA-producing taxa. Alternatively, altered bile acid metabolism might guide modifications in fat intake or targeted probiotic selection. This approach is evidence-aligned: interventions are chosen to shift specific biochemical activities detected in the gut ecosystem. ## Practical considerations Functional testing typically involves a stool sample collected at home and analyzed for metabolite levels, gene-expression proxies, or pathway markers. Interpretation emphasizes patterns of activity rather than binary presence/absence, and integrates clinical context such as diet, medications, and symptoms. While functional data add complexity, they also reduce ambiguity compared with composition-only reports. ## Further reading Explore how gut microbiome status intersects with other systems, for example skin and hair, at Gut microbiome role in skin and hair health and sleep and energy at How gut health impacts sleep and energy. A functional perspective is complementary to compositional analyses and supports more targeted, physiology-oriented interpretation. For an integrated explanation of the platform’s focus on function, see the [InnerBuddies microbiome function test](https://www.innerbuddies.com/blogs/gut-health/beyond-diversity-why-innerbuddies-focuses-on-microbiome-function-test-for-better-gut-health). (Optional product information: microbiome test product page)