At-home gut microbiome tests are trending, selling insights to the curious, empowerment to the chronically ill and a claimed path to longevity to the wellness-conscious.
Private companies are offering tests, costing $100 to $500 or more, that promise a bacterial inventory of your intestines.
But can microbiome tests actually provide actionable health information?
As more patients arrive at doctors appointments with results in hand, frustrated gastroenterologists want people to know the tests have limits.
There’s a world in your gut and we still don’t know a lot about it
Inside our intestines, entire ecosystems of bacteria help us digest our food, absorb key vitamins, combat inflammation and much more. Research shows a healthy gut microbiome may play a role in preventing things like liver disease and diabetes and could even influence mental health.
The gut microbiome is incredibly complex and our understanding of it “is in its infancy,” said Dr. Mark Benson, a gastroenterologist for the University of Wisconsin-Madison’s health system.
On top of that, each person’s gut microbiome is unique, like a fingerprint. It can even vary within one person’s gut.
”Most of the variability between people, we don’t understand,” said Dr. Eamonn Quigley, the chief of gastroenterology and hepatology at Houston Methodist Hospital, who has spent 30 years researching the gut microbiome and disorders of gut-brain interactions, like irritable bowel syndrome.
What can doctors do with the test results?
Physicians sometimes order stool tests, but they typically are looking for specific problems: infections, inflammation from foodborne illnesses or antibiotic use, or cancer.
When patients come in with their own results from an over-the-counter test, there is little advice to give.
“If you talk to patients, these tests are appealing. They’re cool. They’re all this data,” said Dr. Sean Spencer, a physician scientist at Stanford University. The frustration for doctors, he said, is with the lack the tools to change the microbiome.
Spencer, Quigley and Benson have all had patients bring them the results of microbiome tests. But antibiotics and diet are really the only proven tools doctors have to change the gut microbiome, Spencer said.