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Frequently Asked Questions About Weight Loss Surgery

What Are the Pros and Cons of Various Weight Loss Surgeries? continued...

Gastric Bypass Surgery

The Pros:

  • Weight loss is quick and dramatic. People lose an average of 38% of their excess body weight in the first year, and 62% of excess body weight in two years.
  • Because weight loss is quick, weight-related health problems such as diabetes, high blood pressure, high cholesterol, arthritis, sleep apnea, and heartburn improve quickly.
  • Many people keep most of the weight off for 10 years or longer. After 10 years, the average weight loss is 25%.
  • Loss of stomach tissue results in a drop in the so-called "hunger hormone" Ghrelin, which helps control appetite.

The Cons:

  • Gastric bypass surgery is riskier and is associated with more complications. Although the surgery is generally safe, 10% of people have minor complications. Less than 5% have serious (potentially life-threatening) complications. The risk of death is under 1%.
  • The surgery may result in dumping syndrome, which occurs when food moves too quickly through the stomach and intestines. Dumping syndrome can cause shaking, sweating, dizziness, nausea, and severe diarrhea.
  • Gastric bypass is generally considered irreversible. The surgery permanently changes how your body digests food.


What Are Typical Risks After Weight Loss Surgery?

Typical risks associated with weight loss surgery include:

  • Vomiting from eating too much too quickly and not chewing well
  • Constipation
  • Nutritional deficiencies such as anemia, osteoporosis, and metabolic bone disease

As with any surgery, wound infections can occur up to three weeks after surgery. These can be treated with antibiotics, and sometimes require further surgery.

Complications that may develop following weight loss surgery include:

  • Hernia
  • Gallstones
  • Ulcerations
  • Gastric prolapse
  • Severe scarring of the new stomach pouch
  • Excess skin that may need to be removed in an additional surgery
  • Dehydration
  • Hair loss
  • Kidney stones
  • Hypoglycemia

Rare but serious complications include:

  • Bleeding in the stool, or black stools
  • Leaks in new connections made by weight loss surgery; these usually occur within five days of surgery.
  • Blood clots in the lungs, called pulmonary emboli, occur less than 1% of the time; they are the most common cause of death after weight loss surgery. Blood clots can be prevented with blood thinning medicines and frequent activity.
  • Blood clots in the legs, called deep vein thrombosis, or DVT
  • Pneumonia


How Much Weight Will I Lose After Surgery?

After gastric bypass surgery, people generally lose 61% of excess weight. One long-term follow-up study found that 25% of the excess weight remained off 10 years later.

After gastric banding, people lose on average 47% of their excess weight. About 13% of it remained off 10 years later, according to the long-term study.


How Does Weight Loss Surgery Affect Overall Health?

Obesity-related medical problems will generally improve after weight loss surgery. These include:

  • Obstructive sleep apnea
  • Type 2 diabetes
  • Gastroesophageal reflux disease (GERD)
  • High cholesterol
  • Degenerative joint disease or orthopedic problems
  • High blood pressure
  • Asthma
  • Urinary incontinence


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