At-home microbiome testing kits are becoming more and more popular and promise to discover secrets about your gut and health. But can you trust their results? 

What Do These Tests Measure?

Most kits use either 16S rRNA gene sequencing or shotgun metagenomics. These are methods that identify bacterial DNA in stool samples. However, they are quite complex to use for individuals (Gibbons & Duvallet, 2020; Marchesi & Ravel, 2015).

Analytical Reliability: Still Questionable

A comparative study on commercial kits found significant variability between results. The difference appeared even when the same sample was sent to different labs — or to the same one twice (Gibbons & Duvallet, 2020). In other words, your microbiome result is very changeable every day. 

On top of that, the way how a stool sample is collected and stored plays a huge role as it can change the results (Leite et al., 2020).

Health Claims: Far From Solid

Although some companies claim their tests can guide diet, fitness, and even mental health plans, most lack clinical approval (Hooker & Dinan, 2020). It is difficult to understand in general how a healthy microbiome should look like.

Stat News (2019) also criticized DTC microbiome kits for making correlation-based claims that don’t reflect causality. It means they might find patterns, but can’t prove what’s causing what. Thus, you can’t rely on them only, neither to identify the issue nor to cure it. 

Researchers at the University of Maryland also warn these tests have low analytical and clinical validity for diagnosing or treating disease (Leite et al., 2020).

Are There Any Trustworthy Kits?

Yes — there are exceptions. The Evvy vaginal microbiome test, for instance, is CLIA-, CAP-, and CLEP-certified, and their internal validation reports show over 90% sensitivity and specificity (Evvy, 2023). So while gut microbiome tests are still not perfect, there are some niche ones that can be trusted. 

Bottom Line for You

• Microbiome tests can be informative and easy to use, but they shouldn’t guide you in making major health decisions.
  

• Most tests are still more exploratory than actionable (Hooker & Dinan, 2020).
  

• Repeating tests over time with the same company can help show index changes, even if the overall accuracy is questionable.
  
  

What You Can Do Instead

• Stick to the well-known gut health habits such as healthy diets, enough sleep time and active lifestyle (Wilmanski et al., 2021).       

• Check your microbiome results regularly and take other tests together with tracking the symptoms of your body.

• Stick mainly to the clinically proven tests and diagnostics (Evvy, 2023).   

                                                                                                  

Conclusion 

Even though you want to keep track of your gut health by taking a microbiome test, you should mostly pay attention to your lifestyle to improve it. Don’t put all your trust in the at-home microbiome testing. But if you choose to take it, gather multiple samples as they can differ each time. And make sure the test you’re using is clinically proven!

Stay active and sleep well!

 

References

• Evvy. (2023). Evvy Clinical Validation Report. Retrieved from https://www.evvy.com

• Gibbons, S. M., & Duvallet, C. (2020). Microbiome testing: How should consumers evaluate accuracy and usefulness? Nature Microbiology, 5(9), 1096–1098. https://doi.org/10.1038/s41564-020-0774-0
  

• Hooker, C. A., & Dinan, T. G. (2020). Microbiome-based personalized nutrition: Is it science or marketing? Current Opinion in Biotechnology, 61, 140–146. https://doi.org/10.1016/j.copbio.2019.10.005
  

• Leite, G., Morales, W., Weitsman, S., Chang, C., Oh, D., & Pimentel, M. (2020). The effect of stool collection and storage conditions on the DNA integrity and data quality of gut microbiome sequencing. BMC Microbiology, 20(1), 45. https://doi.org/10.1186/s12866-020-01742-z
  

• Marchesi, J. R., & Ravel, J. (2015). The vocabulary of microbiome research: A proposal. Microbiome, 3, 31. https://doi.org/10.1186/s40168-015-0094-5
  

• Wilmanski, T., Diener, C., Rappaport, N., Patwardhan, S., Wiedrick, J., Lapidus, J., ... & Price, N. D. (2021). Gut microbiome pattern reflects healthy ageing and predicts survival in humans. Nature Metabolism, 3(2), 274–286. https://doi.org/10.1038/s42255-020-00348-0