Meet Our Team
Arnold Petersen, MD
Medical Director
Dr. Arnold Petersen’s journey in medicine began with a heart for service and a deep sense of purpose. After earning his medical degree with A.O.A. honors from Loma Linda University in 1966, he completed his internship at Portland Adventist Hospital. But rather than jumping straight into private practice, Dr. Petersen took a detour that would shape his entire approach to care — a mission term at Davis Memorial Hospital in Guyana, South America, where he served with compassion and resourcefulness in a place where both were desperately needed.
Upon returning stateside, he completed his OB/GYN residency at White Memorial Hospital in Los Angeles and earned board certification from the American Board of Obstetrics and Gynecology in 1974. Over the years, he became known not just for his skill in the operating room, but for his warm, reassuring bedside manner — the kind that makes patients feel truly seen and cared for.
Dr. Petersen has pursued advanced training in pelvic endoscopic surgery, CO2 and KTP/YAG lasers, and operative hysteroscopy. He’s also trained and taught neonatal resuscitation and advanced life support in obstetrics. In leadership roles, he has served as chair of the OB/GYN department and Laser Committee at Portland Adventist Medical Center, and continues to advise on OB policy and medical malpractice reform.
For the past 20 years, Dr. Petersen has expanded his focus to: helping people lose weight, reclaim their health, and feel good in their own skin using hCG protocols. Patients often say he cares more about their health than they do — and it’s true. He listens deeply, explains thoroughly, and never stops learning. Even after decades of practice, Dr. Petersen remains committed to staying at the forefront of medical knowledge, all in service of giving his patients the best care possible.
Stacey Lindquist
Program Director
Stacey Lindquist didn’t just learn about the hCG weight loss program — she lived it. For years, she struggled with stubborn weight, trying one method after another without lasting success. That all changed in 2006, when she discovered the original Dr. Simeons hCG protocol and met Dr. Arnold Petersen. The transformation that followed didn’t just change her body — it changed her life.
Fueled by her personal success and a deep desire to help others find the same freedom, Stacey dove headfirst into training. She was certified at the International Symposium of hCG Treatment of Obesity and Associated Morbidities, and since then has spent nearly two decades guiding and supporting others on their weight loss journeys. She’s helped thousands of patients shed over 25,000 pounds of unwanted — and often extremely stubborn — fat.
Stacey holds a Bachelor of Science in Psychology from the University of Oregon, a background that brings insight and empathy to every conversation she has with clients. Her lived experience, combined with her training and hands-on results, has made her an invaluable partner to Dr. Petersen and a trusted guide for every patient walking through the doors of Portland hCG.
Her story is proof that real transformation is possible — and she’s made it her life’s mission to help others find that same confidence, health, and renewed energy for life.
Liz Cook
Medical Assistant
For nearly two decades, Liz Cook has been one of the first friendly faces patients see when they walk through our doors — and one of their biggest cheerleaders throughout their journey. A certified Medical Assistant through the AAMA, Liz has been with our clinic for 18 years and brings not just skill, but heart to everything she does.
Over the years, Liz has witnessed the life-changing transformations of thousands of clients, watching them shed pounds and gain confidence. But her belief in the hCG Weight Loss Clinic isn’t just professional — it’s personal. Liz has her own powerful story of success, having lost nearly 80 pounds with the very same protocol she now supports every day. She knows exactly what it’s like to face the mirror and want something more, and she brings that empathy to every conversation.
Liz is more than a medical assistant — she’s a true brand ambassador for hCG Weight Loss Clinic. Her dedication, warmth, and lived experience make her an irreplaceable part of our team, and a source of hope and encouragement for everyone beginning their own transformation.