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Take the First Step to a Healthier You!

Take the First Step to
a Healthier You!

The Advanced Bariatrics Team

Bariatric surgeons Dr. Hsin-Yi Chang and Dr. John Cheregi and their team are committed to helping people overcome the challenge of obesity to discover happier, healthier lives. The medical weight loss specialists at Advanced Bariatrics guide each step of this life-changing journey to help patients turn their dreams into weight loss success stories in a warm, judgment-free environment. 

Hsin-Yi Chang, MD

“The ideal patient-doctor relationship is one in which both people are listening and learning. I want my patients to understand the pros and cons of every procedure we are discussing. Together, we’ll find the best path forward. I’ll be with them throughout their journey.”

John Cheregi, MD

“I want my patients to feel that I’m here at every step of the way. This is a life-changing journey. From the very first conversation about the challenges you face – through surgery and follow-up – we are right by your side. We are committed to helping you reach your goals.”

Kiersten Kern


Medical Assistant – Dr. Cheregi



Medical Assistant – Dr.Chang


Practice Manager

Kiersten and Melissa are the bariatric coordinators for Dr. Cheregi and Dr. Chang. They guide our patients through the entire  process and act as the main point of contact for all questions. It is their passion and goal to be able to support the patients on their journey and help them achieve their weight loss goals.

Erin ensures that our program and practice always keeps its focus on the health and well-being of our patients. It brings her great joy to be able to provide support not only to the physicians and staff but also to our patients.

Take the First Step to a Healthier You!

Take the First Step to
a Healthier You!