Stephen J.D. O'Keefe, MBBS, MD, MSc, MRCS, FRCP

Dr. O’Keefe performs translational research into the physiological and pathophysiological responses to feeding and nutritional deprivation. He has received NIH R01 grant support for his studies on the physiological effects of feeding in pancreatic enzyme synthesis in humans with and without disease, the optimal feeding in patients with severe acute pancreatitis, and, most recently, the role of diet, the microbiome, and its metabolites in determining colon cancer risk in extreme-risk Alaska Natives, high-risk African Americans (AA), and minimal risk rural South Africans (NA). His pivotal 2015 study in Nature Communications showed that switching the diets of AA and NA (i.e., Americans were given a traditional African diet high in fiber, low in meat and fat, while Africans were given a westernized diet high in meant and fat and low in fiber) led to profound changes in the colonic microbiome and its metabolome and reciprocal changes in colonic mucosal biomarkers of cancer risk within two weeks. This supports the hypothesis that diet drives colon cancer risk and that it is largely preventable by a high fiber diet. Studies are underway in Alaska to determine whether fiber supplementation will annul the health disparity and extreme rates of colon cancer risk and mortality in Alaska Natives. Finally, Dr. O’Keefe is partnering with the University of Stellenbosch in South Africa to direct the African Microbiome Institute to study the ecology of the microbiome through the Faculties of Medicine, Agrisciences, and Plant Biology, with the overarching aim of improving the health of all Africans.

Dr. O'Keefe's research interests are linked to his clinical interests. He has 40 years experience in nutritional gastroenterology, stimulated by his unique combination of postgraduate degrees in Medicine and Human Nutrition. His theses were based on the application of stable isotope labeling techniques of amino acids to measure in vivo protein metabolic responses in humans to a variety of GI diseases, including surgical trauma, liver failure, acute and chronic pancreatitis, the short bowel syndrome and intestinal transplantation. These measurements were used to determine the acute metabolic effects of these diseases and their associated rates of protein catabolism to design the most effective forms of metabolic support of malnourished hospitalized patients. There application of these techniques led to paradigm changes in the routine enteral and parenteral nutritional support, summarized in his solo authored "The Principles and Practice of Nutritional Support" (Springer Publ 2015). Dr O'Keefe has played a leadership role in the nutritional support of hospitalized patients, patients with intestinal failure dependent on home IV and enteral feeding, and patients following small bowel transplantation at UPMC. His research into the etiology of colon cancer has added the clinical interest of improving peoples' diets to prevent colon cancer, the second leading cause of cancer deaths worldwide.

Dr. O'Keefe's education effort is focused at the advanced postgraduate and specialist levels, with a focus on international efforts and health disparities. First, the training doctorate and postgraduate students, medical students, and GI fellows. Secondly, his services are in high demand nationally and internationally for lecturing specialists in the areas of nutrition, nutrition support, and more recently, diet and GI cancer. He spent 4 years as vice Chair, and then Chair of the American Gastroenterology Association's Nutrition Section, where his responsibilities were to design educational programs for practicing and academic gastroenterologists, and GI trainees. Working in Africa, he founded the first African Society for Clinical Nutrition - the South African Society of Enteral and Parenteral Nutrition and served subsequently as its President. He has served on educational and symposium organization committees for the equivalent American and European Societies, as well as for Experimental Biology (ASN, ASBMB) and the American Association for Cancer Research. As mentioned above, the publication of his textbook on The Principles and Practice of Nutritional Suooprt was aimed at educating undergraduates, postgraduates, medical students, doctors, and hospital specialists on appropriate artificial feeding of sick patients.