Everything Is Just Dandy!

Microbiologist tries at-home test kits to see what they reveal about microbiome

Ars Technica
The Conversation
2022-08-16
https://theconversation.com/which-microbes-live-in-your-gut-a-microbiologist-tries-at-home-test-kits-to-see-what-they-reveal-about-the-microbiome-181392

Which microbes live in your gut?

When you hear about the gut microbiome, does it ever make you wonder what tiny creatures are teeming inside your own body? As a microbiologist who studies the microbiomes of plants, animals and people, I’ve watched public interest in gut microbes grow alongside research on their possible dramatic influence on human health. In the past several years, microbiome testing techniques used by researchers like me are now available to consumers at home. These personal gut microbiome testing kits claim to tell you what organisms live in your gut and how to improve your gut microbiome using that data.

I became very interested in how these home test kits work, what kind of information they provide and whether they can really help you change your gut microbiome. So I ordered a few kits from Viome, Biohm and Floré, tried them out and sifted through my own microbiome data. Here is what I learned.

Your gut microbiome can be a partner in your health—if you have the right bacteria.

How do gut microbiome kits work?

All gut microbiome kits require you to carefully collect fresh fecal material. You put it in the various tubes provided in the kit and mail the samples back to the company. Several weeks later, you’ll receive a report describing the types of microbes living in your gut and suggestions on how to change your diet or activities to potentially alter your gut microbiome.

What consumers don’t exactly know is how companies generate the microbial profile data from your fecal sample. A typical approach I and other microbiome researchers use is to extract and decode the microbial genetic material from a sample. We use that genetic material to identify what species of microbes are present. The challenge is that this process can be done in many different ways, and there are no widely agreed-upon standards for what is the best method.

Different home gut microbiome test kits can give conflicting results.

Enlarge / Different home gut microbiome test kits can give conflicting results.

For example, microbiome analyses can be done on two types of genetic material, RNA or DNA. If the profile is based on DNA, it can give you a snapshot only of what types of microbes are present, not what microbial genes are active or what activities they are doing in your body. On the other hand, if the profile is based on RNA, it can tell you not only what microbes are present, but also whether they’re playing a role in your digestion or producing metabolites that can reduce gut inflammation, among other functions. Viome generates its profiles by looking at RNA, while the other companies use DNA.

Other data analysis choices, such as how different types of genetic sequences are sorted or which databases are used to identify the microbes, can also affect the level of detail and utility of the final data. Microbiome scientists are usually very careful to point out these nuances when interpreting their own data in scientific papers, but these details are not clearly presented in home microbiome kits.