Division of Gastroenterology and Hepatology: New Chief, New Recruits, New Pathways


In 2016, the Weill Department of Medicine welcomed David E. Cohen, M.D., Ph.D., as Chief of the Division of Gastroenterology and Hepatology. Dr. Cohen previously served as Director of Hepatology at Brigham and Women's Hospital and Director of the Harvard-MIT Division of Health Sciences and Technology. His laboratory is leading the frontiers of molecular regulation of nutrient metabolism and energy homeostasis by membrane lipids. Recently named Editor-in-Chief of Hepatology, the leading journal in its field, Dr. Cohen is driving the division towards new horizons with an emphasis on state-of-the-art research and novel collaborations. He has been actively advancing the division’s distinguished history. “In 5 to 10 years, we hope to be a division where all clinicians and basic researchers are collaborating together and answering questions about human digestive diseases in a way that will offer our patients the absolute most current care available – whether that be the most current patient care or through a clinical trial,” says Dr. Cohen.

Dr. David Cohen

Dr. David E. Cohen

A world-renowned expert on the molecular regulation of hepatic lipid and glucose metabolism, Dr. Cohen has brought to Weill Cornell a critical new line of research that focuses of one of the world’s most challenging conditions: obesity. His studies are examining nonalcoholic fatty liver disease (NAFLD) while unraveling the key aspects of this condition and its risk factors, which are implicated in obesity-related disorders (e.g., NAFLD, type 2 diabetes, coronary artery disease, as well as an increased predisposition to cancer).

Nonalcoholic fatty liver disease, as the term implies, is a condition wherein a patient does not drink excess alcohol, yet accumulates unhealthy fat in the liver as if they did drink too much. NAFLD is strongly associated with obesity and affects 25% of the world’s population. “The cost to treat NAFLD is over 100 billion dollars for those 60 plus million Americans who have this condition and who receive medical care for it. It is estimated that it costs $1,600 per patient per year to cover doctor visits and blood tests,” explains Dr. Cohen. “While industry is focused on ways of getting rid of NAFLD, which may include drugs or surgical approaches, one thing we do know for sure is that losing weight works. If you lose 10% of your body weight, at whichever point it is discovered a person has NAFLD, then you will see progress from a medical standpoint – glucose improves, joint stress is relieved, blood pressure stabilizes.”

While the practical approach to losing weight is implemented in the clinical setting, Dr. Cohen’s laboratory has been achieving landmark findings to solve a particular mystery involved in weight gain. His work has defined and characterized genetic mechanisms that appear to be part of a process where the body conserves, or seeks to save, calories. “Trying to understand the genes that we think evolved in the human body in order to conserve calories is central to our research. Conserving calories was an important evolutionary adaptive mechanism in the past. Because if you didn’t know where your food was coming from within three days, it was necessary for the body to conserve calories in order to survive. Today, there is widespread overfeeding and overnutrition occurring. Those old genes are no longer helpful. If we can figure out the key genes responsible for this conservation mechanism, then we can inhibit those genes.”

When Dr. Cohen was recruited to Weill Cornell, he brought on board three of his Harvard colleagues: Drs. Baran A. Ersoy, Tibor Krisko, and Hayley T. Nicholls. Dr. Ersoy is directing an independent laboratory focused on the hepatic metabolism and insulin resistance. Dr. Nicholls is also working in the Cohen laboratory on the role of the microbiome in regulating energy expenditure and glucose metabolism. Dr. Krisko is providing clinical care coupled to research on metabolic liver disease (NAFLD) and the gut microbiome. Recently, Dr. Cohen has recruited several more top tier physicians and investigators, including Drs. Kristy A. Brown, David L. Carr-Locke, and Philip O. Katz.

Under the leadership of Dr. Cohen, the Division of Gastroenterology and Hepatology is expected to experience exponential growth over the next decade. Dr. Cohen’s studies are receiving funding from the National Institutes of Health spanning to 2020 and beyond. Dr. Cohen looks forward to continued collaborations with investigators in his own division, other departmental divisions and institutes, as well as with The Rockefeller University, Memorial Sloan-Kettering Cancer Center, and other medical centers. New lines of study for therapeutic drug treatments and clinical trials are also in view.