Gerard E. Mullin, MD, is an associate professor in the department of medicine as well as director of integrative gastroenterology nutrition services at the Johns Hopkins Hospital. He is an internist, gastroenterologist, and nutritionist and the only physician in the United States who is board certified by the American Board of Internal Medicine for Gastroenterology, National Board of Nutrition Support Certification, American College of Nutrition, and the American Board of Nutrition Physician Specialists.

Laura E. Matarese, PhD, RD, LDN, FADA, CNSD, is an assistant professor of surgery at the University of Pittsburgh School of Medicine and director of nutrition for the Intestinal Rehabilitation and Transplantation Center at the Thomas E. Starzl Transplantation Institute, the University of Pittsburgh Medical Center. She is the author of over 150 books, chapters, manuscripts, abstracts, and videos and currently serves on the editorial boards of several journals.

Melissa Palmer, MD, is medical director of hepatology at New York University Hepatology Associates Plainview and clinical professor of medicine at NYU Langone Medical Center. She graduated from Columbia University with a BA and was trained in hepatology at the Mount Sinai School of Medicine in New York City. She is the author of the best-selling book Dr. Melissa Palmer's Guide to Hepatitis and Liver Disease and runs the popular liver website www.liverdisease.com.