Â鶹´«Ã½

News — Scientific research has linked a person’s microbiome to everything from gut and mental health to immunity and predisposition to cancer. This research comes at a time when there is a burgeoning interest in wellness and alternative medicine, which has fueled consumers’ curiosity about the composition of their own microbiomes.

This curiosity has led to a growing demand for direct-to-consumer (DTC) microbiome testing services. While the companies marketing these services claim to tell customers whether their microbiomes (gut, vaginal, skin…) are “healthy,” researchers from the University of Maryland, Baltimore Schools of Law, Medicine, and Pharmacy question the tests’ accuracy.

In a unique multidisciplinary collaboration, the researchers call for greater regulation of these products in a Perspectives article published March 15 in Science. , Director of the Law and Health Care Program and the Jacob A. France Professor of Health Care Law at the University of Maryland Francis King Carey School of Law, led the collaboration.

The perspective is the result of a that consisted of consultations with experts in food and drug law, microbiome sciences, gastroenterology, gynecology, government regulations, and bioethics as well as focus groups with clinicians and consumers using the products.

DTC microbiome testing services identify which microorganisms are present along with their relative abundance in a fecal or vaginal sample that the consumer collects. In some cases, the test may describe the metabolic functions of the microbes observed.

“There is a perception among consumers that these products will give them a real medical diagnosis and a way to treat an ‘unbalanced’ microbiome,” said , co-author and Acting Director of the Institute for Genome Sciences and Professor of Microbiology and Immunology at the University of Maryland School of Medicine (UMSOM). “There is no scientifically agreed-upon definition of a ‘healthy’ microbiome; the microbiome is dynamic and changes frequently; there is no clinical proof that these products work; and no standardization in the processes involved.”

For consumers—who often suffer from diseases such as inflammatory bowel disease (IBD) or bacterial vaginosis (BV)—that means shelling out a lot of money for a test without a guarantee of useful or actionable medical information—and then often further investing in what companies tell them will help improve their microbiome, such as nutritional supplements including probiotics and prebiotics, or special diets. None of these interventions have been clinically validated or had their claims evaluated by the U.S. Food and Drug Administration (FDA).

“In addition to the cost, these tests could do real harm by convincing a person to delay medical care and substitute supplements for prescription medications,” added Dr. Ravel, who studies the vaginal microbiome.

“We’re calling for federal regulators with oversight of these testing companies to set standards for the analytical validity of their tests and require them to report on their performance,” said Hoffmann. “Additionally, the FDA needs to determine if DTC microbiome tests are general wellness tests or if they make diagnostic claims that could harm consumers. If it is determined that these are diagnostic tests, then FDA regulation will be required.”

In addition to the FDA, the authors write that government bodies like the National Institute of Standards and Technology (NIST) should set standards for the tests, including laboratory methods so that test results are accurate, can be trusted, and are comparable across labs; the Centers for Medicare and Medicaid Services (CMS) under the Clinical Laboratory Improvements Amendments (CLIA) should regulate the analytical validity of the tests, including the testing methods and algorithms used to formulate a report and should require the testing companies to adopt agreed upon standards and report their performance.

“We need further research and clinical evaluation before any of these companies can claim a relationship between a test result and a person’s health, or if dietary changes and supplements can improve the microbiome and someone’s health,” said Hoffman.

“There are more than 60,000 pharmacies in the United States, and these are the source for at least some of supplements that testing companies recommend,” said , Professor Emeritus of Practice, Sciences, and Health Outcomes Research at the University of Maryland School of Pharmacy. “Pharmacists should be made aware of the issues these unregulated laboratory tests present, since they are in a position to counsel customers who buy these supplements.”

All the authors agree that claims these testing companies make are premature and that additional clinical research and peer-validation is necessary before consumers can have confidence in the results. Additional co-authors were Erik von Rosenvinge, MD, Professor of Medicine in the Division of Gastroenterology & Hepatology at UMSOM and Chief of Gastroenterology at the VA Maryland Health Care System; Mary-Claire Roghmann, MD, MS, Professor of Epidemiology and Public Health at UMSOM, and Daniel McDonald, PhD, Scientific Director of the American Gut Project and the Microsetta Initiative at the University of California San Diego.

About the University of Maryland Francis King Carey School of Law 

The University of Maryland School of Law was authorized by the Maryland legislature in 1813 and began regular instruction in 1824. It is the third oldest law school in the nation, but its innovative programs make it one of the liveliest and most dynamic today. Maryland Carey Law stands among five other professional schools on the University of Maryland, Baltimore campus. It has taken advantage of this location to become an integral part of the Baltimore-Washington legal and business community.

About the University of Maryland School of Medicine

Now in its third century, the University of Maryland School of Medicine was chartered in 1807 as the first public medical school in the United States. It continues today as one of the fastest growing, top-tier biomedical research enterprises in the world -- with 46 academic departments, centers, institutes, and programs, and a faculty of more than 3,000 physicians, scientists, and allied health professionals, including members of the National Academy of Medicine and the National Academy of Sciences, and a distinguished two-time winner of the Albert E. Lasker Award in Medical Research. With an operating budget of more than $1.2 billion, the School of Medicine works closely in partnership with the University of Maryland Medical Center and Medical System to provide research-intensive, academic, and clinically based care for nearly 2 million patients each year. The School of Medicine has more than $500 million in extramural funding, with most of its academic departments highly ranked among all medical schools in the nation in research funding. As one of the seven professional schools that make up the University of Maryland, Baltimore campus, the School of Medicine has a total population of nearly 9,000 faculty and staff, including 2,500 students, trainees, residents, and fellows. The School of Medicine, which ranks as the 8th highest among public medical schools in research productivity (according to the Association of American Medical Colleges profile) is an innovator in translational medicine, with 606 active patents and 52 start-up companies. In the latest U.S. Â鶹´«Ã½ & World Report ranking of the Best Medical Schools, published in 2023, the UM School of Medicine is ranked #10 among the 92 public medical schools in the U.S., and in the top 16 percent (#32) of all 192 public and private U.S. medical schools. The School of Medicine works locally, nationally, and globally, with research and treatment facilities in 36 countries around the world. Visit 

About the University of Maryland School of Pharmacy

Established in 1841, the University of Maryland School of Pharmacy is ranked 14th out of more than 140 schools of pharmacy by U.S. Â鶹´«Ã½ & World Report. The School is a thriving center for professional and graduate education, pharmaceutical care, research, and community service. Its faculty create the future of pharmacy by pioneering new roles for pharmacists in advanced clinical practice and conducting cutting-edge research in drug discovery and development, comparative effectiveness and patient-centered outcomes, and disease management. A contemporary curriculum, innovative educational experiences, and strategic professional relationships help to inspire excellence in the School’s more than 1,000 students, residents, and postdoctoral fellows. The School offers 10 academic programs: Doctor of Pharmacy; PhD programs in Palliative Care, Pharmaceutical Health Services Research, and Pharmaceutical Sciences; and MS programs in Medical Cannabis Science and Therapeutics, Palliative Care, Pharmaceutical Health Services Research, Pharmaceutical Sciences, Pharmacometrics, and Regulatory Science. With a research portfolio of more than $38.5 million in grants and contracts, the School is ranked 9th by the American Association of Colleges of Pharmacy amongst schools of pharmacy. In 2017, the School launched its exclusive Pharmapreneurship® program, which describes the School's commitment to supporting and best positioning both faculty and students to achieve their career aspirations and address our nation's health care challenges.

About the Institute for Genome Sciences

The Institute for Genome Sciences' (IGS) has been part of the University of Maryland School of Medicine (UMSOM) since 2007. IGS scientists work in diverse areas, applying genomics and systems biology approaches to better understand health issues in premature infants, women, and transgender people; to improve vaccine development; to study evolutionary biology; and to understand cancer, parasitic, fungal, and infectious diseases, as well as identifying the underpinnings of aging, brain development, addiction, and mental health. IGS also remains at the forefront of high-throughput genomic technologies and bioinformatics analyses through its core facility, Maryland Genomics which provides researchers around the world with cutting-edge, collaborative, and cost-effective sequencing and analysis.

About the University of Maryland, Baltimore

The was founded in 1807 as the Maryland College of Medicine, which now stands as the nation’s oldest public medical school. In response to growing social and cultural needs, UMB’s mission has evolved and grown tremendously. Widely recognized as a preeminent institution, UMB serves as the academic health, law, and social work university of the University System of Maryland and is guided by a mission of excellence in education, research, clinical care, and public service.

UMB is a thriving academic health center combining cutting-edge biomedical research, exceptional patient care, and nationally ranked academic programs. With extramural funding totaling $654 million in Fiscal Year 2022, each tenured/tenure-track faculty member generates an average of $1.5 million in research grants each year. More than 3,100 faculty members conduct leading-edge research and develop solutions and technologies that impact human health locally and around the world. World-class facilities and cores, as well as interprofessional centers and institutes, allow faculty to investigate pressing questions in a highly collaborative fashion. As a result, the more than 7,000 students, postdocs, and trainees directly benefit from working and learning alongside leading experts as they push the boundaries of their fields. For a listing of the organized research centers and institutes, visit: