Credentials & Education

  • Undergraduate: University of California, Santa Barbara
  • Medical School: University of California, San Diego
  • Internship: Cedars Sinai
  • Internal Medicine Residency: Cedars Sinai
  • Gastroenterology Fellowship: University of California, Los Angeles
  • Masters of Science, Clinical Research: University of California, Los Angeles

Academic Appointments

  • Clinical Chief, Division of Gastroenterology Cedars Sinai Medical Center
  • Assistant Clinical Professor, UCLA Geffen School of Medicine

Four Board Certifications

  • Gastroenterology & Hepatology: American Board of Internal Medicine, Subspecialty Gastroenterolgy – 2008
  • Internal Medicine: American Board of Internal Medicine – 2004
  • Bariatric Medicine (Obesity Medicine): American Board of Obesity Medicine – 2012
  • Clinical Nutrition: American Board of Physician Nutrition Specialists (ABPNS) – 2004

Rated #1 Gastroenterologist in LA

Dr. Treyzon is rated the best gastroenterologist in Los Angeles by patient reviews on This site offers a forum for patients to rate their overall experience with a physician. Read More »

Television & Video Appearances

Dr. Leo Treyzon answers a handful of questions on his appearance on the Dr. Oz Show. Among other things, Dr. Leo gives his 5 top tips for living a long, healthy life. Read More »

Received the 2012 Compassionate Doctor Award

Every month, more than 200,000 patients across the U.S. provide online feedback about their doctor experiences. They rate various components of the care they receive, such as bedside manner, doctor-patient face time, follow-up care, ease of appointment setting and courtesy of office staff. They also share their overall opinions. While physicians generally receive positive feedback from their patients, only a select few receive praise about the compassion that accompanied their care. Read More »