James F. Marion MD is an Assistant Clinical Professor at Mount Sinai School of Medicine.

Dr Marion earned his BA in biochemistry at the University of California and his MD from Columbia University College of Physicians and Surgeons. He completed his residency in internal medicine at New York Presbyterian Hospital and his fellowship in Gastroenterology at Mount Sinai Hospital. He is currently in private practice in Manhattan and is very active in clinical research.

Dr Marion is a member of the Scientific Advisory Committee of the New York Chapter of the Crohn's & Colitis Foundation of America, as well as the National Patient Education committee of the CCFA.

Dr Marion is the author of numerous articles, book chapters, lectures, and other publications.