Phone: 303-662-1191

Fax: 303-662-1343

Address: 10099 Ridgegate Parkway
Conifer Building Suite 390
Lone Tree, CO

Gastric Bypass Weight Loss Surgery

In recent years, better clinical understanding of procedures combining restrictive and malabsorptive approaches has increased the choices of effective weight loss surgery for thousands of patients. By adding malabsorption, food is delayed in mixing with bile and pancreatic juices that aid in the absorption of nutrients. The result is an early sense of fullness, combined with a sense of satisfaction that reduces the desire to eat.

According to the American Society for Bariatric Surgery and the National Institutes of Health, Roux-en-Y gastric bypass is the current gold standard procedure for weight loss surgery. It is one of the most frequently performed weight loss procedures in the United States. In this procedure, stapling creates a small (15 to 20cc) stomach pouch. The remainder of the stomach is not removed, but is completely stapled shut and divided from the stomach pouch. The outlet from this newly formed pouch empties directly into the lower portion of the jejunum, thus bypassing calorie absorption. This is done by dividing the small intestine just beyond the duodenum for the purpose of bringing it up and constructing a connection with the newly formed stomach pouch. The other end is connected into the side of the Roux limb of the intestine creating the "Y" shape that gives the technique its name. The length of either segment of the intestine can be increased to produce lower or higher levels of malabsorption.


  • The average excess weight loss after the Roux-en-Y procedure is generally higher in a compliant patient than with purely restrictive procedures.
  • One year after surgery, weight loss can average 77% of excess body weight.
  • Studies show that after 10 to 14 years, 50-60% of excess body weight loss has been maintained by some patients.
  • A 2000 study of 500 patients showed that 96% of certain associated health conditions studied (back pain, sleep apnea, high blood pressure, diabetes and depression) were improved or resolved. 
  • There is 30-89% improved survival after 5-10 year follow up from gastric bypass studies. 


  • Because the duodenum is bypassed, poor absorption of iron and calcium can result in the lowering of total body iron and a predisposition to iron deficiency anemia. This is a particular concern for patients who experience chronic blood loss during excessive menstrual flow or bleeding hemorrhoids. Women, already at risk for osteoporosis that can occur after menopause, should be aware of the potential for heightened bone calcium loss.
  • Bypassing the duodenum has caused metabolic bone disease in some patients, resulting in bone pain, loss of height, humped back and fractures of the ribs and hip bones. All of the deficiencies mentioned above, however, can be managed through proper diet and vitamin supplements.
  • A chronic anemia due to Vitamin B12 deficiency may occur. The problem can usually be managed with Vitamin B12 pills or injections.
  • A condition known as "dumping syndrome " can occur as the result of rapid emptying of stomach contents into the small intestine. This is sometimes triggered when too much sugar or large amounts of food are consumed. While generally not considered to be a serious risk to your health, the results can be extremely unpleasant and can include nausea, weakness, sweating, faintness and, on occasion, diarrhea after eating. Some patients are unable to eat any form of sweets after surgery.
  • In some cases, the effectiveness of the procedure may be reduced if the stomach pouch is stretched and/or if it is initially left larger than 15-30cc.
  • The bypassed portion of the stomach, duodenum and segments of the small intestine cannot be easily visualized using X-ray or endoscopy if problems such as ulcers, bleeding or malignancy should occur.

Related Procedures

Alternative Procedures

Questions Regarding the Gastric Bypass Procedure?

Free weight loss surgery seminars are available throughout the greater Denver, Colorado area on a monthly basis.  These relaxed informational seminars are for the benefit of our patients to learn more about procedures like gastric bypass. Dr. Chae and his friendly staff answer questions, discuss options, and provide information on the latest weight loss surgery news. Sign up is available online or by phone at 303-662-1191. Come join us and take your first step on the journey to a healthier you!

For those who are unable to attend a public seminar, free individual or group meetings with Bariatric specialist, Dr. Frank Chae, are available for those in the Denver and greater Colorado area, please call our friendly staff and we would be happy to assist you.

More Information

The staff of the National Bariatric Center™ in Colorado work to inform patients. If you would like further information please send us an e-mail using our online form or telephone our Denver, Colorado office at 303-662-1191. Additionally, if you are in the Colorado area and would like a personal consultation, give us a call.

National Bariatric Center™: Denver, Colorado Location

The National Bariatric Center™ is located in the Rocky Mountain heartland of America at Sky Ridge Medical Center in beautiful Lone Tree, Colorado (southern metro Denver ).  Our state of the art medical center complex is situated next to highways I-25 and C-470 in the Littleton-Highlands Ranch region, and conveniently accessible to international airports in Denver and Colorado Springs . 

10099 Ridge Gate Parkway, Conifer Building Suite 390
Sky Ridge Medical Center
Lone Tree , Colorado  

Phone 303-662-1191     
Fax 303-662-1343



"I have lost 210 pounds since the start of my journey. What I liked so much about Dr. Chae is that he is a follow up guy, he makes sure that you understand everything about the procedure and that all your questions are answered."

Bryan N.
Denver, CO

Join Dr. Frank Chae and the staff to learn about the latest news and options for Obesity/Weight Loss Surgery. 

April 6, 2019 - 10:00am to 11:30am
Sky Ridge Medical Center