The science of our gut microbiome is often portrayed as one of medicine’s hottest new areas, but some argue that this research is overhyped. The latest aspect of this field to gain traction is test kits that allow you to send in a stool sample to find out if your gut bacteria are impacting your health.

Analysis found that these kits made claims that were not supported by evidence and that their testing procedures were not rigorous enough. So should companies even be allowed to sell them?

Research into the microbiome began about 20 years ago, with advances in DNA sequencing allowing scientists to learn more about our bodies and the bacteria that live within them.

Doctors have long known that some infectious diseases are caused by an overgrowth of harmful pathogens. The innovative idea is that more subtle microbiome disturbances can lead to conditions normally thought to have nothing to do with our gut, such as obesity, cancer and depression. did.

Despite the hype, this field has yet to change the world of medicine. Fecal transplants (transferring one person’s stool to another’s to increase beneficial bacteria) have so far been approved for only one rare medical condition. It is a severe form of diarrhea that usually affects hospitalized patients taking strong antibiotics. Additionally, probiotic products that purport to deliver “good bacteria” to the gut have generally not yet been shown to be effective in randomized trials, the gold standard of medical evidence.

But that hasn’t stopped some companies from selling microbiome-related products directly to the public. In response, the US National Institutes of Health launched an investigation into the increased use of fecal test kits by the general public.

Diane Hoffman Researchers from the University of Maryland identified 31 companies around the world that offer direct-to-consumer microbiome analysis kits. Based on the results of these analyses, users may be provided with a comprehensive report on their gut health, for example in the form of a numerical score, or told that their gut bacteria are associated with certain medical conditions. there is.

The big problem, Hoffman says, is that the science behind fecal DNA analysis is not yet advanced enough to draw reliable conclusions. Previous research has shown that Giving the same sample to different laboratories can give different results. This may be due to differences in how samples are processed or the reference databases companies use to determine someone’s microbiome.

Companies typically do not provide details about how they conduct their analysis, considering it commercially sensitive. “They don’t have to provide any information,” Hoffman said.

A further problem is that even if we could accurately quantify how much of each bacterial species is in someone’s feces, there is still no debate among doctors about which bacteria are associated with specific medical conditions or gut health. There’s a lack of consensus, Hoffman said. “They don’t have the data they need to determine whether someone’s gut microbiome is healthy or unhealthy.”

Some of the companies selling these tests have conflicts of interest. The research team found that nearly half of manufacturers sell supplements and probiotic products that claim to improve gut health and recommend them to consumers based on test results.

The findings are not surprising. leslie hoyles He is co-author of a review on the field at Nottingham Trent University in the UK. natural microbiology Last year, it concluded that the country was susceptible to “hype and misinformation.” When it comes to fecal testing, “it varies so much from person to person that it’s meaningless,” she says. “We don’t know what a healthy microbiome is.”

It might be tempting to think that if people want to waste money on fecal test kits, they should be allowed to do so. However, many other types of direct-to-consumer medical tests, such as pregnancy tests and COVID-19 tests, are regulated by government agencies and require sufficient supporting evidence. It’s time for microbiome testing to meet the same standards, Hoffman says.

No one is arguing that microbiome research should be abandoned. Although there is great promise in this field, it is clear that it is still in its early stages. So for now, it may be wise to just continue flushing your stool down the toilet.