Dr. Oliak is a board-certified, fellowship-trained, ASMBS Center of Excellence bariatric surgeon who has an established record (>2500 patients) of excellent patient outcomes.* Dr. Oliak offers sleeve gastrectomy, gastric bypass, and revisional bariatric surgery in Orange County, California.

About Orange County Bariatric Surgeon Dr. Oliak

Dr. Oliak knew he wanted to be a doctor since the third grade. Unlike most elementary and junior high school kids, for fun he liked to read books about anatomy and physiology. He is the only kid he knew who had a subscription to Scientific American magazine.

He did question his career ambitions while in college at Northwestern University in Chicago. He thought that it might be a better life decision to choose a career that didn’t require 4 years of school beyond college, and an additional 3-6 years of residency training.

Dr. Oliak changed his major from biology (premed) to chemical engineering. After his junior year, he worked as a summer chemical engineering intern at Proctor & Gamble on a project to make laundry detergent for the Philippine market using palm oil. This was a great experience, but he couldn’t get excited about Philippine laundry detergent. This helped him to decide with certainty that he really wanted to be a doctor.

Dr. Oliak attended medical school at top-ranked Washington University School of Medicine in St. Louis. During medical school he decided that he wanted to be a surgeon, and continued on after medical school to a six-year general surgery residency at Harbor-UCLA Medical Center in Los Angeles.

Why Weight Loss Surgery?

It was during his 2nd year of residency that Dr. Oliak decided that he wanted to specialize in weight loss surgery. In no other field of surgery could one operation enable something as difficult and desired as weight loss, and improve or resolve a large range of medical problems. He also found that no other field of surgery had such happy patients!

During his residency in the late 1990’s, the most common weight loss operation was open gastric bypass. Laparoscopic gastric bypass was considered experimental. Dr. Oliak’s belief was that laparoscopic gastric bypass would eventually become the standard of care, and would revolutionize the field of weight loss surgery.

Dr. Oliak wanted to learn laparoscopic gastric bypass, so after residency training he continued on to a one year laparoscopic surgery fellowship at Hackensack University Medical Center in New Jersey. This fellowship was one of the first laparoscopic surgery fellowships in the country to focus on laparoscopic weight loss surgery.

After finishing his fellowship training Dr. Oliak returned to California to start his career as a Los Angeles and Orange County bariatric surgeon.

Career Philosophy – Orange County Bariatric Surgeon Dr. Oliak

Dr. Oliak’s career philosophy has always been to treat patients how he would want to be treated himself. The #1 thing Dr. Oliak would want is a surgeon who achieves excellent patient outcomes. Outcomes after weight loss surgery are variable between different surgeons and programs – Dr. Oliak’s goal has always been to achieve outcomes that rank among the best in the weight loss sugery field.*

By always prioritizing excellent surgery and excellent patient care (education, follow-up, support), Dr. Oliak has established a long record (>2500 operations since 2002) of excellent, industry-leading patient outcomes.*
About our program
About our outcomes

Currently, Orange County weight loss surgeon Dr. Oliak performs sleeve gastrectomy, gastric bypass, and bariatric revision operations. He has offices in Brea and Irvine, and operates at several Orange County bariatric surgery center of excellence hospitals. Dr. Oliak offers free, no-obligation educational consultations to patients considering weight loss surgery.
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Professional Accomplishments

Dr. Oliak was the first Orange County bariatric surgeon to complete a laparoscopic bariatric surgery fellowship, and one of the first Orange County bariatric surgeons to routinely perform laparoscopic gastric bypass surgery rather than open gastric bypass surgery.

Dr. Oliak has developed two successful center of excellence bariatric programs in Orange County, one at Chapman Medical Center, and one at Placentia-Linda Hospital.

Dr. Oliak has published numerous outcomes-focused research studies, including studies on the learning curve for laparoscopic bariatric surgery, studies on outcomes for higher BMI patients, and studies on outcomes for older patients. Dr. Oliak has published his research in numerous scientific journals and has presented his data at national and international surgical meetings.

Orange County bariatric surgeon Dr. Oliak is a sought out weight loss surgery expert. He is a bariatric surgery consultant and bariatric surgery expert witness for bariatric surgery malpractice matters. He has appeared on national television shows, including The View (video clip) and The Tyra Banks Show (video clip), and on local news stations, including KCAL and CBS.

* Patient results vary after weight loss surgery. Individual patients can do better or worse than the average.

** Leaks can occur after gastric surgery. Past performance is no guarantee of future results. Orange County bariatric surgeon Dr. Oliak’s 0% leak rate statistic applies to primary (non-revision) sleeve gastrectomy, primary (non-revision) laparoscopic gastric bypass, LAP-BAND® conversion to sleeve gastrectomy, and LAP-BAND® conversion to gastric bypass.

  • 15+years experience
  • 2500+weight loss operations
  • 0%leak rate**
Dr. Oliak’s Blog

Orange County bariatric surgeon Dr. Oliak

Variation in Outcomes at Bariatric Surgery Centers of Excellence

A new study (read abstract) entitled "Variation in Outcomes at Bariatric Surgery Centers of Excellence" published in the Journal of the American Medical Association reports a surprisingly wide variation in patient outcomes across accredited bariatric surgery centers of excellence nationally. Claims data were analyzed from 145,527 patients who underwent weight


Our Gastric Sleeve Patient Outcomes - 2016

It's a new year which means it is time to evaluate our performance for the previous year, and update our outcomes statistics. This is am important and ongoing part of our practice. Dr. Oliak's #1 goal since starting his weight loss surgery practice in 2002 has been to achieve not


The cost? Losing weight and gaining health is easier than you think.

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Call 714-582-2530 or submit the following information to request a free insurance verification (if necessary), and a free, no-obligation, educational consultation with Dr. Oliak.

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