Editor's note: This article was published on StatNews on January 2, 2024 and was written by Dr. Sameer Berry, an assistant professor of clinical medicine at New York University School of Medicine. Compiler Cao Zhi, the content is for reference.
Blue Muffin Challenge(A 2019 test promoted by a professor at King's College London who sent blue muffins to volunteers around the world to determine the gastrointestinal health of those who took them based on when they passed the blue waste).Food Sensitivity Test KitsMicrobiome test kits……At present, self-service gastrointestinal health testing is in the limelight. There is some plausibility to this phenomenon: 1 in 4 Americans suffer from digestive disorders, and our diet is getting worse, our sleep is getting worse, and our stress is getting more and more stressful, making our hearts twisted (hence the preference for all sorts of self-help tests).
Gastroenterologists like me often see people spend hundreds or even thousands of dollars at their own expense on microbiome kits, as well as products like food sensitivity tests, black mold test kits, and more. While these "tests" are attractive, they rarely provide actionable recommendations and often lead to more questions than answers. Worse, they can lead to "complacency" or missed diagnoses, as these tests can cause patients to choose not to seek out those specialized medical services.
I myself am particularly interested in the field of consumer-based microbiome testing. Some companies promise that testing can identify the root cause of gut microbial imbalances and inflammation, and provide information (recommendations) for personalized nutrition and supplementation based on the test results. However, so far, most of them are not supported by evidence (empirical) and are over-promised and under-fulfilled (not as effective).
Unfortunately, many patients come to my office and have been suffering unnecessarily for years as they try to optimize their microbiome based on fuzzy test results, but the reality is that there is no substitute for working with a trained gastrointestinal dietitian who has the expertise to identify the crux of thousands of potential dietary triggers for bloating, constipation, or pain.
To be clear, scientists have indeed made progress in population-based microbiome research for certain gastrointestinal infections and can even detect early-stage oral cancers through microbiome testing. However, there are no legitimate microbiome tests (products and services) on the market that are worth recommending to their patients. A handful of consumer-based microbiome services companies are entering this space the right way, providing objective and unbiased evidence (conclusions) based on individual test results, but without the promise of ** or alleviating symptoms. In the not-too-distant future, microbiome testing may provide a directed diagnosis or prognostic opinion rather than a definitive answer.
However, for those desperately seeking answers, most of the microbiome remains uncharted territory and has limited clinical value in helping individual patients. What clinicians are most concerned about is that many companies are taking advantage of patient pain and profiting from selling their own supplements by selling these tests or test results.
To be clear, I support allowing patients to learn more and get data about their bodies. But I'm very concerned that companies may use baseless claims to market these tests as a panacea for people's ailments.
In consumer-based microbiome testing, there are three hurdles we need to overcome:
1.Define a "good" conclusion
Microbiome testing is difficult to provide meaningful direction because microbiologists lack sufficient consensus on what bacterial strains or diversity are "best". In other words, microbiologists disagree on the definition of a healthy gut microbiome. Some specific strains, such as Clostridium difficile, can cause significant health hazards – although this is certain – but no one knows whether one microbiome profile is necessarily better than another. Most microbiome testing companies create their own unique oversimplified scoring systems, but when medical scientists don't know what "good" is, what exactly do they mean by "healthy" or "unhealthy."I often see patients make dangerous restrictions on their diets — avoiding dairy products while not consuming other foods or supplements that contain calcium or vitamin D, or avoiding foods that contain gluten without using substitutes to guarantee fiber intake — as a means of "boosting" their microbiome test scores.
2.Retest reliability
If you use different microbiome test kits for the same stool sample, you may get different results for your microbiome composition analysis. This stark discrepancy in test results suggests that many of today's test suites are not precise. Benjamin Wolfe, an expert in microbiology at Tufts University, recently wrote an article about his experience of using three different test kits for the same stool sample, with results ranging from "not very good" to "good." When test results conflict, it can be difficult for users to know the true condition of their body. To be clear, this issue is largely a reflection of the current state of available testing services today – poor retest reliability.
3.Your microbiome changes from day to day
Research shows that our microbiome changes daily due to factors such as the food we eat, lifestyle (including exercise and stress). As a result, a person's gut composition may change between the time they are tested and the time the results are available two weeks later, which will result in the user getting an "outdated" test result. Again, it's unclear how to explain these changes scientifically, and how to make recommendations based on test results that may vary from day to day, and whether these changes are clinically significant.
Unfortunately, these tests are still far from being able to alleviate chronic disease** and suffering in reality. Many companies charge patients a fee, essentially asking them to test their products and provide the data to these companies for research, and the purpose of this service is not to alleviate the user's symptoms. Some microbiome companies have gone from skyrocketing to rapid collapse, such as UBIOME and Evelo Bio.
On the other hand, gastrointestinal disorders continue to cause distress to patients, who often seek solutions outside of traditional medical interventions. Quality of life scores for patients with irritable bowel syndrome are worse than those on dialysis – in a landmark study, 50% of irritable bowel patients said they were willing to give up 15 years of life expectancy in exchange for being "on the ground" today, and these statistics illustrate the immense suffering these patients are experiencing. It may be tempting for businesses in question and self-proclaimed experts to take advantage of their pain and suffering to make a profit, but it is not an ethical business practice.
While the technology behind evidence-based microbiome testing has potential, at least for now, it is "not ready for its most advanced stage of development."
What is the best way to keep your microbiome healthy?My answer: eat 30 different plants a week – a variety of fruits, vegetables, legumes, nuts, seeds, whole grains, herbs and spices. Of course, this is not easy to achieve, but if you do care about it, it is the best way to do it in terms of the time, effort, and money consumed.