Understanding Microbiome Testing: What It Promises

Ah, the microbiome, the future of medicine, the forgotten battleground by many. The microbiome (trillions of bacteria living in harmony within our gut) is a highly complex system that has emerged in public health and media over the last decade and is definitively linked to several disease states. We are finding more (and more) out about just how crucial a balanced microbiome is, and how significant the impact can be if it is not. But how can you tell if your microbiome is balanced? There are two very specific tools that can help: amplicon sequencing (such as 16S rRNA gene sequencing) and whole-genome shotgun metagenomic sequencing. 

There are a lot of initial search results when you look this up, but be wary of gimmicky companies promising a comprehensive look at your gut bacteria. In fact, consider discussing with your primary care doctor how to best test your microbiome before submitting a sample to an online retailer that costs an arm and a leg. There are no FDA-approved at-home gut microbiome tests, and none have been validated for their effectiveness in assessing overall health. Similarly, at this time, we still do not have a benchmark for what is considered healthy or symbiotic. Mayo Clinic is hoping to change this. 

The Current Scientific View on Efficacy

Mayo Clinic established a very interesting microbiome tool last year, called the Gut Microbiome Wellness Index 2, a metagenomic-based indicator for assessing health and even determining the likelihood that an individual has a chronic disease state (beyond other clinical indications). This index tool was established after evaluating over 8,000 stool samples and their associated microbiome activities and has high reliability for distinguishing between healthy and unhealthy gut phenotypes. The overview of this index and the respective meta-analyses is extensive and not in layman’s terms, but it does offer a detailed explanation of gene mapping, analysis, and how it can function as a predictor for overall health. The goal of this tool is to determine a ‘baseline’ microbiome for healthy individuals and establish a standard ‘symbiotic profile’. 

Navigating Results and Future Directions

Our understanding of the microbiome as a society is still in its infancy, and we have much more to learn. At this time, discussing with a licensed health care provider is the recommended route for mapping your microbiome. Research is ongoing, with several multi-year studies underway (e.g., the Human Microbiome Project). Until a benchmark for a ‘normal’ gut can be established, hold off on those at-home biome analysis tests and instead consider participating in clinical trials. Overall, the microbiome is exciting! It feels like an alternative universe we’ve discovered, with native hosts and living organisms. More to come on this exciting new(ish) medical landmine. 

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