What is bariatric surgery?
Bariatric surgery, also referred to as weight loss surgery, includes a group of procedures designed to help people with obesity reduce their weight. It is typically recommended when other weight loss methods have not been effective and when the health risks associated with obesity outweigh the risks of surgery.
These surgeries work by changing parts of the digestive system, most often the stomach and sometimes the small intestine, to limit how much food can be eaten and how many nutrients can be absorbed. They may also influence the hunger signals that travel from the digestive tract to the brain.
Bariatric surgery can help prevent or improve many health conditions related to obesity, including diabetes and fatty liver disease. However, it is not a quick or simple fix. Long-term success depends on thorough preparation and permanent lifestyle changes.
Why is bariatric surgery performed?
Bariatric surgery is considered the most effective long-term treatment for severe obesity. People with high levels of obesity often find it very difficult to maintain weight loss using only diet and exercise. Once the body adjusts to a higher weight, it tends to return to that level. Bariatric surgery changes how the body processes and responds to food, helping support sustainable weight loss and improved overall health.
What conditions can bariatric surgery help with?
Obesity is linked to many chronic health issues, some of which are life-threatening. Bariatric surgery often leads to significant improvement or even resolution of the following conditions:
- High cholesterol (hyperlipidemia): Too much fat in the bloodstream can clog arteries and increase the risk of heart attack or stroke.
- High blood pressure (hypertension): Elevated blood pressure can damage blood vessel walls and increase the chance of cardiovascular events.
- High blood sugar (hyperglycemia): Often linked to insulin resistance, high blood sugar can damage nerves, blood vessels, and organs if left untreated.
- Type 2 diabetes: Excess fat contributes to insulin resistance, raising the risk of adult-onset diabetes. The risk increases with higher BMI values. Bariatric surgery has been shown to improve blood sugar control and, in many cases, result in remission of type 2 diabetes, especially when performed early in the condition’s progression.
- Heart disease: Obesity can impair heart function, cause plaque buildup in arteries, and increase the risk of heart failure, heart attack, or stroke.
- Kidney disease: Obesity-related conditions such as high blood pressure and insulin resistance are major contributors to chronic kidney disease and kidney failure.
- Obstructive sleep apnea: This condition causes breathing interruptions during sleep due to blocked airways, which reduces oxygen flow to the body and stresses vital organs like the heart.
- Osteoarthritis: Carrying extra body weight increases stress on joints, particularly the knees, and can worsen or trigger joint degeneration.
- Fatty liver disease (NAFLD): Fat buildup in the liver can lead to inflammation and scarring, eventually causing long-term liver damage.
- Cancer: Obesity is linked to a higher risk of developing several types of cancer and is also associated with a greater risk of cancer-related death.
Treatment Details
Who qualifies for bariatric surgery?
Eligibility for bariatric surgery typically begins with a diagnosis of severe obesity. A person may qualify if they:
- Have a BMI of 40 or higher, which generally corresponds to being approximately 45 kilograms or more above a healthy weight and carries a high risk of health complications
- Have a BMI of 30 or higher along with at least one obesity-related health condition
For adolescents, the requirements are slightly stricter:
- A BMI of 40 or more with at least one obesity-related condition
- A BMI of 35 or more with a more severe obesity-related condition
Additional medical tests may be needed to confirm related health conditions.
Common myths about bariatric surgery
- Myth: Surgery is only for extreme cases or a last resort
In fact, bariatric surgery is one of the most effective long-term treatments for severe obesity. Diet, exercise, and medication are often less successful at maintaining weight loss over time. - Myth: Surgery is the easy way out
Many individuals have already made these efforts before surgery, but their bodies resisted those efforts. Bariatric surgery is neither an easy solution nor a shortcut, but rather a tool that enables sustained weight loss hand in hand with healthier eating and lifestyle habits.
Preparing for bariatric surgery
Before surgery is scheduled, your general surgeon will assess your readiness from both physical and mental perspectives. He will also explain the benefits and risks and evaluate your overall health.
Your doctor may also ask you to follow a special diet before the operation. This is done to reduce the amount of fat in the abdomen and make the procedure safer. You will be given specific dietary guidelines to follow.
How is weight loss surgery performed?
Most weight loss surgeries are done using minimally invasive methods, such as laparoscopic surgery. This involves small incisions and results in quicker recovery, less pain, and minimal scarring compared to open surgery. In certain cases, open surgery may be more appropriate depending on individual medical needs.
Types of bariatric surgery
- Gastric Sleeve (Sleeve Gastrectomy)
This is the most commonly performed weight loss surgery. It involves removing approximately 80 percent of the stomach and creating a small, tube-shaped pouch. This limits the amount of food you can eat and reduces hunger hormone production, which helps regulate appetite and metabolism.
- Gastric Bypass
This procedure creates a small pouch at the top of the stomach and reroutes a portion of the small intestine to it. This restricts food intake and also reduces nutrient absorption, making it more effective than stomach restriction alone.
Postoperative care
In the first year after surgery, you will attend regular follow-up appointments to track your progress and monitor for nutritional deficiencies through blood tests. Once your weight stabilizes, you may discuss options like body contouring surgery to remove excess skin and improve comfort and mobility.
Weight loss expectations
Most people lose around 50 percent or more of their excess weight and maintain it over time. The results vary depending on the type of procedure:
- Gastric sleeve: between 30 and 80 percent
- Gastric bypass: around 70 percent of excess weight lost
These results are typically measured 18 to 24 months after surgery.
Risks and Benefits
Risks of bariatric surgery
As with any surgery, there are potential complications. More complex procedures may carry a higher risk. Possible complications include:
- Bleeding
- Infection
- Blood clots
- Hernias
- Small bowel obstruction
- Leaks at the surgical connection points (anastomotic leaks)
Potential side effects
Changes to your digestive system can lead to:
- Dumping syndrome: This occurs when food moves too quickly from the stomach into the intestines, causing nausea, diarrhea, abdominal cramping, or low blood sugar. Symptoms often improve over time and with dietary adjustments.
- Malabsorption and malnutrition: Some surgeries reduce how many nutrients the body can absorb. This can lead to vitamin deficiencies and loose stools. Nutritional supplements are prescribed to prevent this.
- Bile reflux: If the valve between the stomach and small intestine doesn’t function properly, bile can backflow into the stomach, irritating the lining and increasing the risk of ulcers.
- Gallstones: Rapid weight loss increases the cholesterol content of bile, which may lead to gallstone formation. Medication may be used to prevent gallstones after surgery.
Benefits of bariatric surgery
- Sustained weight loss: Bariatric surgery is the most effective treatment for long-term weight loss in people with severe obesity.
- Improved metabolism: The surgery helps reset how the body manages hunger, food intake, and energy use, reducing the chances of weight regain.
- Better blood sugar and cholesterol control: Many individuals experience improvement or remission of type 2 diabetes and can reduce or stop medications for related conditions.
- Improved quality of life and longevity: Bariatric surgery not only improves health and reduces obesity-related discomforts but also increases life expectancy and overall well-being.
Recovery and Outlook
Recovery time
Most patients stay in the hospital for a few days and then recover at home over the next few weeks. Strenuous activity should be avoided for about six weeks. A normal diet is usually resumed gradually over the course of three months.
Success rate
Bariatric surgery is considered successful when at least 50 percent of excess weight is lost and maintained. The overall success rate is around 90 percent. Most people experience steady weight loss during the first two years, followed by minor weight regain in some cases, usually not exceeding 25 percent of the weight lost.