Weight loss surgery patient outcomes vary over a wide range between individual surgeons and programs. Some surgeons and programs achieve better weight loss results and lower complication rates than others. Read below about our excellent, industry-leading patient outcomes.*

Our Weight Loss Surgery Patient Outcomes

For the outcomes that matter most, weight loss results and complication rates, our statistics rank among the best in the field, as highlighted below:*

Gastric Sleeve Weight Loss

Gastric sleeve weight loss at 1-3 years after surgery varies between individual surgeons and programs, according to the published literature (reference), from an average of 40-50% excess weight loss, to an average of 70-80% excess weight loss.*

The industry average surgeon/program gastric sleeve weight loss, according to published studies (reference) is approximately 55-60% excess weight loss.*

Dr. Oliak’s gastric sleeve patients average 74-77% excess weight loss at 1-3 years after surgery. Dr. Oliak’s sleeve gastrectomy weight loss statistics rank among the best reported surgeon/program statistics, and are significantly better than the industry average gastric sleeve weight loss.*

More About Gastric Sleeve

Gastric Sleeve Leak Rate

The most feared complication after gastric sleeve surgery is leak. Leak rates vary between experienced bariatric surgeons, according to published studies (reference), from 0 in >500 operations, to approximately 1 in 25 operations (0-4%). Less experienced bariatric surgeons can have leak rates as high as 7%.*

The industry average bariatric surgeon leak rate, according to several large review studies (reference), is somewhere in the 1-2.5% range.*

Dr. Oliak’s gastric sleeve leak rate is 0%.* This statistic ranks among the best in the field, and is significantly lower than the industry average leak rate.

More About Gastric Sleeve

30-Day Serious Complication Rate

The rate of serious complications occurring within 30 days of weight loss surgery has been reported to vary 17-fold (yes, 17-fold!), from 0.6% – 10.3%, in a large, high-quality study published in 2017 of 165 accredited bariatric surgery center of excellence programs nationwide.*

Using the same methodology and dates as in this study, Dr. Oliak’s 30-day serious complication rate is 0.6%.* This statistic ranks among the best 30-day serious complication rates in the study quoted above.

10-Year Gastric Bypass Weight Loss

The few good published studies on gastric bypass weight loss at 10+ years after surgery report an average of approximately 55-60% excess weight loss (e.g. Pories et al).*

Dr. Oliak’s gastric bypass patients average 65% excess weight loss at 10 years after surgery.

More About Gastric Bypass

More about Dr. Oliak’s Outcomes Statistics

To read about Dr. Oliak’s outcomes statistics in more detail, see the following links:

Gastric Sleeve Weight LossGastric Sleeve Complications

Gastric Bypass Weight LossGastric Bypass Complications

Our Weight Loss Surgery Program

The key to how we achieve excellent, industry-leading patient outcomes is our weight loss surgery program, which prioritizes quality of surgery, comprehensive patient education, frequent follow-up, and ongoing support.*

Our program

* Patient results vary after weight loss surgery. Past results do not guarantee future results. ** Dr. Oliak’s 0% leak rate statistic applies to primary (non-revision) sleeve gastrectomy operations and LAP-BAND® conversion to sleeve gastrectomy operations.

  • 0%
    our gastric sleeve leak rate**
  • 75%
    our excess weight loss 1 year after sleeve*
  • 65%
    our excess weight loss 10 years after bypass*
Dr. Oliak’s Blog

Orange County bariatric surgeon Dr. Oliak

How to Choose the Best Weight Loss Surgery for You

Choosing the weight loss operation best suited for you typically means choosing between the sleeve gastrectomy operation and the gastric bypass operation. These two operations are by far the most popular weight loss operations performed in the United States. Before we discuss the strengths and weaknesses of the gastric sleeve and


Gastric Sleeve Surgery for Patients with Low Initial BMI (BMI 30-35)

I recently wrote a post entitled “Weight Loss Surgery for Low BMI Patients (BMI 30-35).” In this post I reviewed the guidelines published by the ASMBS for weight loss surgery for low BMI patients, and I reviewed some recent published studies on weight loss surgery for low BMI patients. In


Schedule an educational consultation with Dr. Oliak

Learn more about weight loss surgery and our Orange County weight loss surgery program by attending a private educational consultation or a group informational seminar with Dr. Oliak in Brea or Irvine. Call our office or send us a contact form today!

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