Types of Bariatric Surgery: Which Method is Right for You?

Bariatric surgery refers to a comprehensive set of surgical procedures that intervene in the digestive system to provide lasting weight control for individuals who have not been able to reach their target weight through diet and exercise programs, and whose body mass index (BMI) is above a certain level. Different types of bariatric surgery, such as sleeve gastrectomy, gastric bypass, and the gastric balloon, work by either reducing the stomach's volume or restricting nutrient absorption. These surgeries do not merely offer an aesthetic transformation; they also play a vital role in treating chronic obesity-related conditions like diabetes, hypertension, and sleep apnea. The treatment process is a multifaceted journey that includes careful patient selection, detailed pre-operative preparation, and lifelong post-operative lifestyle changes.

At a Glance

• Bariatric surgery is performed for lasting weight control and the treatment of obesity-related comorbidities.
• The most frequently preferred methods include sleeve gastrectomy (gastric sleeve) and gastric bypass operations.
• Individuals with a Body Mass Index (BMI) of 35 and above, or those over 30 with accompanying medical conditions, are generally suitable candidates.
• In the post-operative period, patients follow a special, protein-rich nutrition program that gradually progresses from liquids to solid foods.
• Operations are mostly performed using minimally invasive (laparoscopic) techniques, which significantly shortens hospital stays and recovery times.

What is Bariatric Surgery and Who is it For?

Commonly known as stomach reduction surgery, bariatric surgery involves surgical procedures that alter the anatomy of the digestive system to restrict food intake or impair nutrient absorption. These procedures reduce the stomach's capacity, allowing the person to feel full with much smaller portions. They also regulate the secretion of appetite hormones to increase the feeling of satiety. However, these surgical interventions are not a suitable first option for everyone who wants to lose weight. During the decision-making phase, the patient's medical history, current weight, and overall health status are evaluated in detail.

The primary criterion for determining who is eligible for bariatric surgery is the Body Mass Index (BMI). According to general medical guidelines, individuals with a BMI of 40 and above (morbidly obese) are directly considered candidates for surgery. Individuals with a BMI between 35 and 40 who also suffer from obesity-related comorbidities—such as Type 2 diabetes, severe sleep apnea, high blood pressure, or joint problems—can also benefit from this surgery. In recent medical approaches, surgery may also be recommended in specific cases for patients with a BMI in the 30-35 range who have uncontrolled metabolic syndrome. Candidates are generally expected to be between 18 and 65 years old, have no medical barriers to receiving anesthesia, and possess the psychological maturity to adapt to post-operative lifestyle changes.

What Are the Types of Bariatric Surgery?

In obesity treatment, different methods are preferred based on the patient's eating habits, accompanying illnesses, and anatomical structure. Surgical options are fundamentally divided into two categories: those that restrict food intake and those that both restrict food intake and impair absorption.

Sleeve Gastrectomy (Gastric Sleeve)

Today, sleeve gastrectomy ranks first among the most frequently performed types of bariatric surgery. In this procedure, approximately 80 percent of the stomach is surgically removed, leaving behind a long, thin tube shaped like a banana. Because the stomach's volume is reduced, the patient feels full after eating very small amounts of food. One of the biggest advantages of this procedure is the significant drop in the level of "ghrelin," known as the hunger hormone, which is secreted from the removed upper part (fundus) of the stomach. This naturally decreases the patient's appetite. Since the natural flow of the digestive tract is not altered, vitamin and mineral deficiencies are seen less frequently compared to other methods. For more information, you can read our article titled What is Sleeve Gastrectomy?.

Gastric Bypass

Gastric bypass is a combined surgical method that both reduces stomach volume and decreases the absorption of nutrients. In this operation, the stomach is divided, leaving a small pouch at the top. A specific section of the small intestine is then bypassed and connected directly to this new, smaller stomach pouch. As a result, consumed food continues down the digestive tract without passing through the larger part of the stomach and the first section of the small intestine. Gastric bypass is a highly effective method, especially preferred for individuals who have suffered from severe Type 2 diabetes for many years or those with severe acid reflux complaints. Because absorption is reduced, patients may need to take lifelong vitamin and mineral supplements after the surgery.

Gastric Balloon Application

Although technically not a surgical procedure, the gastric balloon is a frequently used endoscopic method in obesity treatment. A deflated balloon is lowered into the stomach through the mouth and then inflated with liquid or air to take up a large portion of the stomach. This creates an early feeling of fullness. The gastric balloon usually remains in the stomach for 6 to 12 months and is then removed endoscopically. It is often used as a preparatory step for patients with a BMI between 27 and 35 who do not fully meet surgical criteria, or for super-obese patients who need to lose some weight to reduce risks before the main surgery.

The Pre-Operative Preparation Process

Once the decision for bariatric surgery is made, a comprehensive preparation process begins to ensure a safe operation. During this period, the patient is evaluated by a multidisciplinary team consisting of specialists in general surgery, endocrinology, cardiology, pulmonology, psychiatry, and nutrition. The goal is to confirm the patient's suitability for anesthesia and surgery, minimizing any potential risks. Detailed blood tests, an electrocardiogram (ECG), a chest X-ray, abdominal ultrasonography, and an endoscopy are requested as standard procedure.

It is common to detect gallstones or sludge in the gallbladder during ultrasonography, as rapid weight loss can trigger gallstone formation. To get detailed information on this topic, you can read Prof. Dr. Selim Sarı's insights on gallstones. About one or two weeks before the surgery, patients are started on a special "liver-shrinking diet." This low-carbohydrate, protein-rich diet reduces fat in the liver, allowing the surgeon easier access to the stomach during surgery and increasing the safety of the operation.

Post-Operative Nutrition and Recovery

Success after stomach reduction surgery largely depends on the patient's ability to adapt to their new eating habits. During the recovery period, a phased nutrition program is implemented to protect the stomach's staple lines and help the body adjust to its new anatomy. For the first one to two weeks, only clear liquids (beef broth, chicken broth, sugar-free compotes, water) are consumed. From the third week, patients transition to puréed foods (yogurt, blended soups, puréed vegetables). Generally, soft solid foods are introduced by the end of the first month.

The most critical rule to remember in this new phase is that solid foods and liquids must not be consumed at the same time. Liquid intake should be stopped 30 minutes before meals and resumed 30 minutes after eating. Protein intake is a primary priority to prevent muscle loss and support wound healing. Patients must chew their food thoroughly, swallow in small bites, and stop eating the moment they feel full. Regularly taking the vitamin and mineral supplements recommended by your doctor and dietitian is indispensable for your long-term health.

Benefits and Potential Risks

As with any surgical intervention, bariatric surgery has its own unique benefits and potential risks. These two pictures must be weighed together with your physician during the decision-making process.

Benefits of Bariatric Surgery:

• Permanent loss of 60 to 80 percent of excess weight within the first year and a half.
• Significant regression or complete resolution of conditions like Type 2 diabetes, hypertension, and high cholesterol.
• Elimination of sleep apnea and snoring problems.
• Increased mobility due to reduced strain on the knee and lower back joints.
• A marked improvement in psychological well-being, self-confidence, and overall quality of life.

Potential Risks and Complications:

• Standard surgical risks associated with general anesthesia.
• Development of bleeding or infection at the surgical site.
• Leakage of stomach fluid into the abdominal cavity from the staple line (leak risk).
• Blood clot formation in the leg veins (deep vein thrombosis) and clots traveling to the lungs (pulmonary embolism).
• Long-term deficiencies in iron, B12, calcium, and vitamin D due to inadequate nutrition.

When to Go to the Emergency Room

Reading your body's signals correctly in the early post-operative period is vital. After discharge, mild pain, fatigue, or slight nausea while adjusting to fluid intake can be considered normal. However, certain symptoms can be harbingers of serious complications that require emergency medical intervention.

If your fever rises above 38.5°C (101.3°F), or if you feel a sudden, increasingly severe pain in your abdominal area, you should go to the hospital without delay. In cases of persistent vomiting, vomiting blood, blackening of the stool (melena), shortness of breath, chest pain, palpitations, or sudden swelling and redness in the legs, you should immediately call 112 (Türkiye's national emergency number) or go to the nearest fully equipped emergency room. In such situations, our hospital's Emergency Medicine department is ready for immediate intervention 24/7 with its expert staff.

The Bariatric Surgery Process at BHT CLINIC

At BHT CLINIC İstanbul Tema Hastanesi, bariatric surgery is performed with a safe, patient-centered approach in accordance with international JCI quality standards. Your journey begins under the leadership of our general surgery specialists, with a joint evaluation by our endocrinology, dietetics, and psychiatry departments. Surgeries are performed in our fully equipped operating rooms using the latest laparoscopic and robotic surgical technologies.

Following the operation, our patients are under the assurance of our experienced nursing staff and, if needed, our 24/7 intensive care and emergency service support units. After discharge, your adaptation to your new life is closely monitored through dietitian follow-ups and physician check-ups. To take a step towards a healthy future and create your personalized treatment plan, you can book an appointment with our specialists.

Frequently Asked Questions

When can I return to work after bariatric surgery?

Recovery time varies depending on the nature of your job. If you work at a desk job that does not require physical exertion, you can generally return to work 10 to 14 days after the surgery. For those working in jobs that require heavy physical activity, it is recommended to wait 4 to 6 weeks.

Is the surgery risky?

Every surgical procedure carries certain risks. However, when bariatric surgery is performed using the laparoscopic (minimally invasive) method by an experienced team in fully equipped centers, the risk rates are quite low. For most patients, the life-threatening risks of remaining morbidly obese are much higher than the risks of the surgery itself.

Will I regain weight after the surgery?

Bariatric surgery is a powerful tool, but it is not a standalone miracle. If the recommended healthy eating habits are not adopted in the post-operative period, if high-calorie liquids are consumed, and if exercise is neglected, you may experience weight regain in the long term as the stomach stretches slightly. Therefore, a permanent lifestyle change is mandatory.

Will there be skin sagging after stomach reduction surgery?

Skin sagging can occur after rapid weight loss. The degree of sagging depends on the patient's age, genetic skin elasticity, how much weight was lost, and whether they exercise regularly. Once the weight loss process is complete and the weight has stabilized (usually after 1 to 1.5 years), these sags can be treated with aesthetic surgical methods.

Can I get pregnant after the surgery?

Yes, you can get pregnant after bariatric surgery, and weight loss actually affects fertility positively. However, to guarantee the health of the mother and baby and to ensure adequate nutrient intake, it is recommended not to get pregnant for at least 12 to 18 months after the surgery.

This article is for informational purposes only; please be sure to consult your physician for diagnosis and treatment.