William D. Chey, MD

Our Research

Disorders of Gut-Brain Interaction (DGBI) affect more than a third of the U.S. population. These conditions, though not associated with cancer or increased mortality, significantly reduce quality of life and work productivity. DGBIs also lead to billions of dollars in health care expenditures on an annual basis. Of the DGBIs, irritable bowel syndrome (IBS), is the most common, affecting an estimated 15% of all Americans. IBS is defined by the presence of typical symptoms, including abdominal pain and altered bowel habits (constipation, diarrhea, or a mixture of both).

In the past 20 years, we have made significant strides in diagnosing and treating patients with IBS. Our understanding of the underlying causes of IBS symptoms has grown at a remarkable rate. Particularly notable is the transition of our thinking of IBS as a primarily psychosomatic condition to one that results from a complex interplay between environmental factors like food and stress, genetic factors, gut factors like the microbiome, immune activation and permeability, and brain factors like mood and pain processing.

William Chey, MD

William D. Chey, MD, AGAF, FACG, FACP, RFF
H. Marvin Pollard Professor of Gastroenterology
Chief and Professor, Division of Gastroenterology and Hepatology
Professor, Department of Nutritional Sciences
Director, GI Physiology Laboratory
Director, Digestive Disorders Nutrition & Behavioral Health Programs
Director, Michigan Food for Life Kitchen
Medical Director, Michigan Bowel Control Program

View Dr. William Chey's CV


About Dr. William Chey

William D. Chey, MD received his medical degree and completed training in internal medicine at Emory University School of Medicine. Dr. Chey then completed a fellowship in gastroenterology at the University of Michigan and has remained as faculty at the University of Michigan where he is the H. Marvin Pollard Professor of Gastroenterology. He holds a joint appointment as a Professor of Nutritional Sciences. Dr. Chey was appointed Chief of the Division of Gastroenterology and Hepatology in May 2022.

Dr. Chey's research interests focus on the diagnosis and treatment of disorders of gut brain interaction and H. pylori infection. He has mentored more than 70 students, residents, fellows, and junior faculty, many of which are leaders in gastroenterology. Dr. Chey is a medical innovator and holds several patents. He is a former Co-Editor-in-Chief of the American Journal of Gastroenterology and has authored more than 400 manuscripts, reviews, chapters, and books including more than 10 national and international clinical practice guidelines. Dr. Chey is a board member of the American College of Gastroenterology, Rome Foundation, International Foundation of GI Disorders, and GI on Demand. He is also the Secretary of the American College of Gastroenterology and Vice President of the International Foundation for Gastrointestinal Disorders.

Dr. Chey has been elected to “Best Doctors” since 2001 and has received the U-M Dean’s Outstanding Clinician Award, U-M Dean’s Award for Innovation and Commercialization, and the Distinguished Clinician Award from the American Gastroenterological Association. In 2020, Dr. Chey was awarded honorary membership in the Academy of Nutrition and Dietetics and received the prestigious Berk-Fise Award from the American College of Gastroenterology.

Treatment Philosophy

This increase in knowledge has led to a paradigm shift in the treatment of IBS patients. Twenty years ago, doctors and scientists would have scoffed at the suggestion of treating an IBS patient with the low FODMAP diet, probiotics, or antibiotics. Yet these treatments are now accepted as effective, evidence-based options for IBS patients. Though we have made incredible strides in the laboratory and the clinic, we still have a long way to go. In the coming years, our group will work tirelessly to translate the emerging science to practical solutions that positively impact patients' lives. We are committed to staying true to the mantra: “Lead not follow”.

  • We will create and/or validate more holistic management models that incorporate not only medications but also diet, behavioral, and complementary/alternative strategies.
  • Through research conducted by our group and collaborations with other academic institutions and industry partners, we will identify biomarkers that will move the diagnosis of patients with DGBIs beyond symptoms alone. The ultimate goal is to accelerate the evolution of clinical care from the current model, which relies almost exclusively on symptoms to choose a treatment for a patient, to a “precision medicine” model in which the choice of therapy will be based on symptoms combined with biomarkers, which will utilize genetics, microbiome, and metabolomics to choose the right therapy for the right patient.
  • We will leverage technology to transform the way that doctors and patients interact and learn from one another. Using novel eHealth platforms, we will utilize big data to transform the clinical care landscape from empirical to precision medicine.

Patient Story

Katy's Story

"I met Dr. Chey while working as a medical assistant in the Medical Procedures Unit (MPU) at UofM when I was in nursing school. I always had a "sensitive" stomach, most likely IBS, as diagnosed by other physicians throughout my childhood. The summer of 2006 was quite different, though. I could never be far from a bathroom, and I lost 10–15 lbs in a matter of just three months. I finally got up the courage to ask Dr. Chey for some advice. Lucky for me, he was doing a study on gastrointestinal disorders using a blood test. Turns out, I got paid $20 to be in the study, and I received my diagnosis of celiac disease, which has ultimately changed my life for the better. Most people wouldn't see this as a good thing, but I feel extremely fortunate to have discovered my diagnosis in just three short months, and I am able to control my symptoms on diet alone without any medications. I immediately felt like a completely new person, and my diagnosis has completely changed how I view gut health and what I am putting in my body. I am forced to read labels, and I live my life by eating whole, unprocessed foods. My energy levels have drastically improved, and I have also had improvements in my hemoglobin, iron, and cholesterol levels. Fast forward to twelve years later, and I am now a CRNA at UofM where I was lucky enough to run into Dr. Chey while providing anesthesia for his patients. Coming full circle, I can't tell him enough how grateful I am for his diagnosis so long ago that has completely changed my life in the best way."

Current Studies


  • Determining the role of diet interventions for abdominal pain and bloating in patients with IBS
  • Conducting studies to determine the most efficient and effective ways in which to utilize the low FODMAP diet in clinical practice
  • Identifying biomarkers that will help health care providers to determine which IBS patients are most likely to improve with the low FODMAP diet
  • Determining whether breath testing identifies IBS patients who are more likely to improve with the non-absorbed antibiotic rifaximin
  • Determine the best test to identify patients with intestinal enzyme deficiencies – an enzyme called sucrase isolmaltase is responsible for breaking down table sugar and starch. Lack of this enzyme can cause symptoms that are identical to lactose intolerance and may be an unrecognized cause of IBS
  • Evaluating the efficacy of a novel vibrating capsule in patients with chronic idiopathic constipation
  • Clinical trials evaluating novel drugs and devices utilizing electrical neuromodulation to improve belly pain in patients with functional dyspepsia and irritable bowel syndrome
  • Invention of a point of service, disposable device which can identify patients with a type of chronic constipation that is best treated with physical therapy and biofeedback as opposed to laxatives
  • Exploring a magnification endoscopy technique called confocal laser endomicroscopy to identify food sensitivities in patients with upper and lower GI symptoms
  • Participating in a multicenter NIH funded trial to determine the best treatment for patients with fecal incontinence

Publication Highlights

AGA Clinical Practice Update on Role of Diet in Irritable Bowel Syndrome: Expert Review
Chey WD, Habash JG, Manning L, Chang L. Gastroenterology. May 2022.
Summary: Concise review and recommendations on diet interventions for patients with irritable bowel syndrome from the American Gastroenterological Association.

Can a Defecation Posture Modifying Device Correct an Abnormal Balloon Expulsion Test in Chronically Constipated Patients?
Koo E, Chey WD, Ezell G, Baker JR, Armstrong M, Nojkov B. Clinical Gastroenterology and Hepatology. January 2022.
Summary: First study to characterize the benefits of a posture modifying device (Squatty Potty) on the ability of constipated patients to defecate.

Development of a Simple, Point-of-Care Device to Test Anorectal Function in Patients with Constipation: Randomized Clinical Trial
Chey WD, Baker JR, Watts L, Harris A, Shah ED. Clinical Gastroenterology and Hepatology. December 2021.
Summary: Validation of a simple, office based device to identify constipated patients with an evacuation disorder.

Exploratory Comparative Effectiveness Trial of Green Kiwifruit, Psyllium, or Prunes in US Patients with Chronic Constipation
Chey SW, Chey WD, Jackson K, Eswaran S. American Journal of Gastroenterology. June 2021.
Summary: The first study from the U.S. characterizing the benefits of kiwifruit in patients with chronic constipation.

ACG Clinical Guideline: Management of Irritable Bowel Syndrome
Lacy BE, Pimentel M, Brenner D, Chey WD, Keefer L, Moshiree B. American Journal of Gastroenterology. January 2021.
Summary: Clinical practice guideline on the management of patients with irritable bowel syndrome from the American College of Gastroenterology.

Behavioral and Diet Therapies in Integrated Care for Patients with Irritable Bowel Syndrome
Chey WD, Keefer L, Whelan K, Gibson P. Gastroenterology. October 2020.
Summary: Comprehensive review of diet and behavioral treatments for patients with irritable bowel syndrome.

AGA Technical Review on the Evaluation of Functional Diarrhea and Diarrhea-Predominant Irritable Bowel Syndrome in Adults (IBS-D)
Carrasco-Labra A, Lytvyn L, Falck-Ytter Y, Surawicz CM, Chey WD. Gastroenterology. July 2019.
Summary: Comprehensive review which informed the development of an international clinical practice guideline on the value of diagnostic testing in patients with diarrhea.

The Impact of a 4-Week Low-FODMAP and mNICE Diet on Nutrient Intake in a Sample of US Adults with IBS-D
Eswaran S, Dolan R, Ball S, Jackson K, Chey WD. Journal of the Academy of Nutrition Dietetics. May 2019.
Summary: The first study from the U.S. to characterize the nutritional impact of the low FODMAP diet in patients with IBS with diarrhea.

ACG Clinical Guideline: Treatment of Helicobacter pylori Infection
Chey WD, Leontiadis G, Howden C, Moss S. American Journal of Gastroenterology. February 2017.
Summary: Clinical practice guideline on the treatment of patients with H. pylori infection from the American College of Gastroenterology.

A Randomized Controlled Trial Comparing the Low FODMAP Diet vs. Modified NICE Guidelines in US Adults with IBS-D
Eswaran S, Chey WD, Han-Markey T, Ball S, Jackson K. American Journal of Gastroenterology. December 2016.
Summary: The first RCT conducted in the U.S. which demonstrated the benefits of the low FODMAP diet compared to usual dietary recommendations in patients with IBS with diarrhea.

View all Dr. Chey's Publications

In the News

Gut Talk – Healio Gastroenterology

Gut Talk, on Healio Gastroenterology, is a podcast hosted by Dr. Sameer Berry and Dr. William Chey that explores the impact of health policy, technology, practice management, and research on the field of gastroenterology. Listen to the podcast.

Education and Resources


Continuing Medical Education

Food: The Main Course to Digestive Health (for RDs/RDNs)
Wednesday - Friday, September 21-23, 2022
DoubleTree by Hilton Ann Arbor North, Ann Arbor
In-Person & Online


Upcoming Resources

  • A mobile app that will help patients to assess their GI symptoms, determine whether their symptoms are related to meals, learn about the ESP low FODMAP program (Elimination, determine Sensitivities, Personalize the low FODMAP diet), and track their progress.

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