Department of Medicine
Faculty Profiles by Division

Division of Gastroenterology, Hepatology and Nutrition

Faculty Profiles

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


Professor of Medicine


Phone: 412-648-7217

Office: Division of Gastroenterology, Hepatology & Nutrition- 200 Lothrop St
UPMC Presbyterian Hospital/ 853 Scaife Hall
Pittsburgh, PA 15213
Phone: 412-648-7217
Fax: 412-383-8913
Education and Training
MB BS, Guy's Hospital Medical School, London, England, 1972
MRCS and LRCP, Royal College of Physicians, London, England, 1972
MSc, London University, 1974
MD (by thesis, equivalent to PhD), London University, 1981
Fellowship, Intern. Med. & Nutrition, Harvard Medical School, 1978
Gatroenterology and Hepatology, King's College, London University, 1980
Research Interest
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.
Clinical Interest
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.
Educational Interest
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.
For my complete bibliography, Click Here.
Selected Publications:
O'Keefe, S.J., Li, J.V., Lahti, L., Ou, J., Carbonero, F., Mohammed, K., Posma, J.M., Kinross, J., Wahl, E., Ruder, E., Vipperla, K., Naidoo, V., Mtshali, L., Tims, S., Puylaert, P,G,, DeLany, J., Krasinskas, A., Benefiel, A.C., Kaseb, H.O., Newton, K. Fat, fibre and cancer risk in African Americans and rural Africans. Nature Communications. 2015; 6: 6342.
O'Keefe SJ. Diet, microorganisms and their metabolites, and colon cancer. Nature Reviews. 2016; 13(12): 691-706.
Ou, J., Carbonero, F., Zoetendal, E.G., DeLany, J.P., Wang, M., Newton, K., Gaskins, H.R., O'Keefe, S.J. Diet, microbiota, and microbial metabolites in colon cancer risk in rural Africans and African Americans. The American Journal of Clinical Nutrition. 2013; 98(1): 111-20.
Jeppesen, PB, Pertkiewicz, M, Messing, B, Ayer, K, Seidner, DL, O'Keefe, SJD. Teduglutide reduces need for parenteral support among patients with short bowel syndrome with intestinal failure. Gastroenterology. 2012; 143(6): 1473-1481.
O'Keefe, S.J., Ou, J., Delany, J.P., Curry, S., Zoetendal, E., Gaskins, H.R., Gunn, S. Effect of fiber supplementation on the microbiota in critically ill patients. World Journal of Gastrointestinal Pathophysiology. 2011; 2(6): 138-45.
O’Keefe, SJD, Lee, RB, Anderson, FP, Gennings, C, Abou-Assi, S, Clore, J, Heuman, D, Chey, W. Physiological Effects of Enteral and Parenteral Feeding on Pancreaticobiliary Secretion in Humans. Am J Physiol Gastrointest Liver Physiol. 2003; 284: G27-G36.
O’Keefe, SJD, Lavender, R. The plight of the modern Bushmen. Lancet. 1989; 255-258.
O’Keefe, SJD, Abraham, R, El-Zayadi, AR, Marshall, W, Davis, M, Williams, R. Increased plasma tyrosine concentrations in patients with cirrhosis and fulminant hepatic failure associated with increased plasma tyrosine flux and reduced hepatic oxidation capacity. Gastroenterology. 1981; 81(6): 1017-24.
O’Keefe, SJD, Abrahams, R, El-Zayadi, R, Williams, R. Malnutrition and immuno-incompetence in patients with liver disease. Lancet. 1980; 2 (8195 Pt 1): 615-7.
1. O’Keefe, SJD, Sender, PM, James, WPT. "Catabolic" loss of body nitrogen in response to surgery. Lancet. 1974; 1034-7.
Sponsored Research/Activities
Title: Randomized Controlled Trial of Resistant Starch to Reduce Colon Cancer in Alaska Native People
Role: Principal Investigator
Funding Agency: National Cancer Institute
Grant Number: R01 CA204403
Start Year: 2017
End Year: 2021
Notable Achievements
NCI-NIH Study Sections (special interest groups and programs), 2003 - Present
VC & Chair, Nutrition & Obesity Section, American Gastroenterology Association, 2003 - 2007
South African Society for Parenteral and Enteral Nutrition (Founder and First Chairman) 1985 and 1986-1987, 1985 - 1987
Editorial Board Gastroenterology Research and Practice, 2013 - Present
External Advisory Committee, Division of Nutritional Sciences, UIUC, 2015-present
Panel Member of Biology & Medicine Panel, Hong Kong Research Grants Council 2015-8, 2014-2016
Associate Editor: Frontiers in Gastroenterology Physiology and Science, 2010 - Present
Assistant Editor-in-Chief: World Journal of Gastroenterology, 2011 - Present
The Leist Visiting Professorship, Mayo Clinic, Nutrition and the Quality of Life following Small, 2006
Governor’s Award for the Best Scientific Paper, American College of Gastroenterology 2000, 2000