Don’t waste money on gut microbiome tests
Dear Doctors: I read your column about improving gut health and want to do it. But I have also read that it’s best to start with a test to get your gut microbiome analyzed. How do those tests work? Do I really need one? I’m on a fixed income and they’re not within my budget
Dear Reader: By now, most people have heard about the gut microbiome. It’s the collection of trillions of microorganisms that make their home in the large intestine. These include vast and diverse communities of bacteria, fungi, protozoa and even helpful viruses. Researchers continue to uncover the many ways the gut microbiome influences health and well-being. These include immune function, blood sugar control, cardiovascular health, cholesterol levels, body weight and even mental health.
This growing understanding of the gut microbiome’s role in health has fueled a new market. This includes the tests you are asking about. Aimed at consumers, they require just a tiny sample of your stool to be mailed to a lab. In return, they promise to analyze the microorganisms living in your gut. They also promise to spot any imbalances and build a personal plan for better digestive health. This typically includes a diet tailored to your specific gut profile. It can also include advice on probiotics, vitamins and other dietary supplements, plus lifestyle guidance.
All of this would be useful if it were truly possible. Our understanding of the gut microbiome is expanding rapidly. But we have not yet fully figured out how complex it truly is. Currently, there is no agreement on what makes a healthy gut microbiome. Research also shows that the gut microbiome changes over time. Each person’s microbiome is as unique as a fingerprint. Because of this, it is not clear whether this kind of personal assessment is even possible. It’s no surprise, then, that consumer-based tests can often overpromise and underdeliver.
The lack of uniform standards also adds to these challenges. Many of these products are marketed as wellness aids rather than diagnostic tests. So there is no single accepted way to read the results. In one recent study, the same stool sample sent to different companies produced very different microbiome profiles and advice. And as you point out in your letter, none of these tests are cheap
The good news for your wallet — and for your microflora — is that the consumer-based microbiome testing you have read about is not needed. As we discussed in that earlier column, you can improve your gut microbiome through lifestyle choices. Diet matters most. Eat fiber-rich plant-based foods. Include fermented foods with live cultures. The former feed the microbes in the gut, and the latter add to gut diversity. Staying physically active supports gut health. Getting good sleep is also key.
The limits of your budget don’t have to limit your progress. The lifestyle measures we discussed remain the safest, most effective and most affordable way to support gut health
(Send your questions to [email protected], or write: Ask the Doctors, c/o UCLA Health Sciences Media Relations, 10960 Wilshire Blvd., Suite 1955, Los Angeles, CA, 90024. Owing to the volume of mail, personal replies cannot be provided.)
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