All sorts of microbiome tests are now available to consumers, but are they any good? The microbiome is the community of microbes (bacteria, viruses, fungi) that live in and on our bodies. Each body part (e.g., sinuses, gut, vagina, skin) has a different microbiome, but the one that has been studied the most (with stool tests) is the gut microbiome.
A recent study by researchers at the US National Institute of Standards and Technology (NIST) evaluated the performance of seven commercial (sold directly to consumers) microbiome kits or tests that promise to give you an analysis of your gut microbiome (and health advice) by analyzing a stool (fecal) sample that you mail them. The researchers found that the test results do not give you dependable or reliable information about the actual composition of your gut flora.
They also found that for the same stool samples there were major discrepancies among the results from different companies, and even from the results of the same identical samples sent to each company (3 of the same stool sample was sent to each company).They found that the same sample could be labeled healthy vs unhealthy by different providers.
They point out that you can't make conclusions or recommendations on how to improve (gut) health from the results because the results are so flawed. [An earlier study of tests from 31 companies found the same kind of flawed results.]
Why is this happening? This is because there is no government regulation or oversight of the tests - thus the test manufacturers don't have to prove that they are reliable and actually measure what they say they measure. There are no quality assurance requirements. No standardization of tests. [An earlier 2024 study of microbiome tests sold to consumers and manufacturer claims found the exact same thing.]
Bottom line: The tests may sound great, but don't do it! The companies typically just want to sell you their supplements - which you probably don't need!
Instead, try to improve your diet - a diet rich in whole foods and fiber, which will also feed your beneficial gut microbes. This includes fruits and vegetables, nuts, whole grains, seeds, legumes, whole grains. Also, some fish, some dairy, eggs, some olive oil. For example, Mediterranean style diet.
From Medscape: Commercial Microbiome Tests: Unreliable Results
Commercial home tests that analyze stool samples promise insights into a person’s gut microbiome. But how reliable are those results? A study published in Communications Biology delivers a sobering verdict: the tested microbiome analyses do not provide dependable information about the actual composition of the gut flora. ...continue reading "Gut Microbiome Tests Sold To Consumers Are Unreliable and Flawed"