What Is a Gut Microbiome Test and Should You Get One? What You Need to Know About the Home Test Kits

Home test kits have been increasing in popularity over the last few hours, and it’s easy to see why. What’s more convenient than being able to gain new insights to your personal health without leaving your house? While we love at-home accommodations, the most important factor to consider when it comes to health tests is, of course, effectiveness and validity of the results. As conversations around gut health ramp up and more people become educated about the importance of the gastrointestinal (GI) tract, gut microbiome tests have increased in popularity. We asked a gastroenterology specialist for her perspective on microbiome testing, and her input might surprise you!

What is the gut microbiome?

The trillions of microorganisms (or phyla) across bacteria, viruses, fungi and yeast that are associated with the digestive-tract make up the gut microbiome. This ecosystem has a relationship with various health and disease factors throughout the body — metabolism, nutrition, physiology and immune function. You’ve likely come across the microbiome in a discussion about gut health, and this is because an imbalanced gut microbiome has been linked to gastrointestinal conditions such as inflammatory bowel disease (IBD) and irritable bowel syndrome (IBS), obesity, type 2 diabetes and atopy.

What is a gut microbiome test?

Manufacturers are offering gut microbiome tests that can be taken at home. These include a variety of testing methods including samples of stool, blood and sometimes even breath which are then evaluated through sequencing. The idea is to identify which microbes are in your gut.

A gastroenterologist weighs in on gut microbiome tests

How reliable are gut microbiome tests?

Janese Laster, MD, gastroenterologist at Gut Theory Total Digestive Care, first notes that there are currently no proven indications that a patient should take a gut microbiome test. If a gut microbiome test is conducted in an office, Dr. Laster says, this is most often strictly for clinical research purposes. As of right now, the medical field doesn’t have enough information about the tests to make recommendations based on them.

Dr. Laster says in her experience, patients who take gut microbiome tests (which are not FDA-approved) do so because they are experiencing GI symptoms and are looking to find a cause or solution themselves.

“The tests are expensive,” she says. “Most times, I have patients bring all of these results back to their physician and say, ‘Okay, now, what do I do with this?’ And the answer is, there’s nothing that we can help you with with this data, because it’s just not validated.”

The other problem Dr. Laster raises about these at-home tests is that conducting them outside of a lab could result in questions of the stool sample’s stability. The process of sending in the sample, including the amount of time that it sits at the post office and in transit as well as temperature fluctuations, poses an issue for the scientific dependability of the results. In a lab, the deposit would go directly to a refrigerator and then to test tubes.

What kind of GI symptoms often lead patients to look for a gut microbiome test?

As Dr. Laster notes, many people will buy gut microbiome tests when they feel that their digestive health is abnormal. Many factors can impact gut microbiome balance, Dr. Laster explains. Diet and nutrition often plays a role and sometimes taking antibiotics or steroids, developing illnesses such as COVID-19 or undergoing cancer treatments can lead to an imbalance.

“What we know so far is that when people have more diversity of these sorts of microbiota, they tend to be healthier, and patients that have a less diverse microbiome are those that tend to be more sick,” she says.

This is so that the good microorganisms can keep the bad in check, but when the body is met with a disturbance, that diversity is hindered and the beneficial phyla die off first. An example of this, Dr. Laster says, is the fact that most medications come with potential GI side effects including diarrhea, constipation, nausea, vomiting and loss of appetite.

With that being said, Dr. Laster notes that the science community is still trying to get a definitive answer in regards to a particular setup or quantity of each phyla that suggests whether a person’s gut is healthy or imbalanced. As of right now, there are only theories.

Preferred gut microbiome health methods

Essentially, gut microbiome tests can provide interesting information, but they’re not an ideal manner of enhancing GI health. Instead, Dr. Laster recommends an in-depth conversation with a nutritionist or gastroenterologist to discuss any GI symptoms you may be experiencing. This way, they can conduct lab or stool tests or conduct a diet recall for things that can actually be identified such as celiac disease or SIBO (small intestinal bacterial overgrowth).

One thing that has been scientifically proven, Dr. Laster says, is the fact that the microbiome can improve in as little as one week with positive dietary changes. This can include reducing processed foods, getting more fiber in your diet or cutting back on dairy if you experience lactose intolerance.

Additionally, Dr. Laster says she tries to limit the amount of supplements her patients take if they are experiencing GI issues, because these products often contain ingredients that are not necessary and disrupt the gut microbiome.

“Just getting routine labs done and some stool studies that test for other infectious type things that can cause people to have symptoms are easy fixes,” she says. “And just making that small change, you’re able to sort of change their symptom and help them to feel better in the process.”

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