Obesity and Diabetes Surgery

Morbid obesity refers to body weight that is dangerously above normal limits. In practical terms, it means that body fat exceeds approximately 30% in women and 25% in men. Clinically, obesity is defined using the Body Mass Index (BMI), which is calculated by dividing body weight (in kilograms) by the square of height (in meters).

• A BMI of 30 kg/m² or higher is classified as obesity.
• A BMI above 35 kg/m² indicates severe obesity, while a BMI of 40 kg/m² or higher is defined as morbid (life-threatening) obesity.

Conditions Caused by Obesity

Obesity is a major risk factor for many chronic and progressive health conditions. It significantly increases the likelihood of developing:

• Type 2 diabetes

• High blood pressure (hypertension)

• High cholesterol and lipid disorders

• Cardiovascular disease, vascular occlusions, and heart attack

• Gastroesophageal reflux disease (GERD)

• Asthma

• Fatty liver disease and potential liver failure

• Gout

• Degenerative joint diseases (arthritis)

• Migraine

• Phlebitis (venous inflammation)

• Polycystic ovary syndrome (PCOS) and menstrual irregularities

In addition, obesity is associated with an increased risk of several cancers, including breast, uterine, colon, esophageal, pancreatic, kidney, and prostate cancers. Importantly, many obesity-related conditions improve significantly—or even resolve completely—once a healthy body weight is achieved.

Obesity Treatment Methods

Although short-term results can be rarely achieved in some patients with diet, exercise, herbal treatments and drug therapies as well as acupuncture and similar alternative treatments, sound results usually fail or the gains cannot be maintained for a long time.

Patients with body mass index above 40 kg/m2 and people with body mass index above 35 kg/m2 and obesity-related diseases, such as diabetes, hypertension, coronary artery disease or sleep apnea, can also undergo obesity surgery.

Metabolic surgery can also be considered for patients with body mass index between 30 and 35 kg/m2 who have type II diabetes that cannot be controlled by drugs and this operation can help selected patients with diabetes mellitus.

Obesity Surgeries

1. Surgeries That Reduce Stomach Volume

a. Sleeve Gastrectomy

Sleeve gastrectomy is the most commonly performed bariatric surgery worldwide. During this procedure, the stomach is reshaped into a narrow tube, allowing patients to feel full with much smaller portions.
Additionally, the section of the stomach responsible for producing ghrelin, the hunger hormone, is largely removed. As a result, appetite is significantly reduced, hunger occurs less frequently, and satiety is achieved more quickly.

b. Gastric Plication

This procedure reduces stomach volume by folding the stomach inward without removing tissue. It remains largely experimental and is not widely used or accepted.

2. Surgeries That Reduce Nutrient Absorption

These procedures bypass a portion of the small intestine, limiting digestion and nutrient absorption. The goal is to allow food to pass through the digestive system before full absorption occurs.

3. Combination Procedures

a. Gastric Bypass (Roux-en-Y Gastric Bypass)
In this procedure, the stomach is reduced to a very small pouch—approximately the size of a teacup—and the small intestine is reconnected to this pouch. Both stomach capacity and nutrient absorption are reduced.
Gastric bypass has been performed for more than 40 years and is considered the gold standard in obesity surgery due to its well-documented long-term outcomes.

b. Mini Gastric Bypass
The stomach is reshaped into a narrow tube and directly connected to the small intestine. This method is highly effective for weight loss and particularly beneficial for patients with type 2 diabetes.
However, it may not be suitable for individuals at risk of bile reflux into the stomach or esophagus. Excellent outcomes can be achieved in carefully selected patients.

c. Transit Bipartition
This technique combines sleeve gastrectomy with an alternative intestinal pathway. Some food follows the normal digestive route, while another portion is diverted.
This approach aims to reduce long-term vitamin and mineral deficiencies while improving blood sugar control through hormonal mechanisms. Although relatively new, early results are promising.

d. Other Surgical Techniques
Procedures such as duodenoileal bypass, jejuno-ileal bypass, and ileal interposition have been described, but they are performed only in highly selected cases. Due to limited long-term data, these procedures are considered experimental rather than standard treatment options.

Use of Gastric Balloon for Weight Loss

The gastric balloon was first introduced in 1982 and remains an effective non-surgical weight loss option. Using an endoscopic technique, a silicone balloon is placed in the stomach and inflated with air or fluid.

On average, patients may lose 20% to 30% of their body weight over 6 to 12 months, depending on balloon type. Many patients are able to maintain approximately 90% of their weight loss during the first one to three years with appropriate lifestyle changes.

Balloon Insertion:

This procedure does not require general anesthesia. Air-filled balloons typically remain in the stomach for up to 12 months, while fluid-filled balloons are usually removed after 6 to 8 months.

The reduced stomach capacity creates a persistent feeling of fullness, helping patients adhere to a personalized diet program. Patients can continue their daily routines and attend scheduled follow-up visits. At the end of the treatment period, the balloon is deflated and removed endoscopically.

Postoperative Period

It is necessary to consult with a dietitian before obesity surgery and obtain detailed information about postoperative nutrition plan. You will be prescribed a diet that is easy to follow. Anatomy and hormone secretions that are modified with the surgery will help you follow this diet. In addition, you are recommended to avoid strenuous exercises for the first 3 months. 

Gentle exercises like walking and swimming are better that do not tire the body too much. You can do any exercise you want 3 or even 6 months after the surgery. Non-sedentary lifestyle is essential to achieve ideal body weight. Also, it is very important to attend follow-up visit at regular intervals in postoperative period. If nothing goes wrong, you should attend follow-up visits quarterly for the first year, semiannually for the second year and annually thereafter.

The medications you take for diabetes, hypertension, high cholesterol or sleep apnea will probably be changed; their doses will be reduced or medications will be stopped. Regardless of type of obesity surgery, some deficiencies may develop secondary to both insufficient eating and malabsorption.

The iron, Vitamin B, calcium or other vitamin and mineral deficiencies detected in the follow-up examinations are usually managed very easily. However, long term deficiencies lead to serious problems if you ignore follow-up visits. This condition is so important that many healthcare facilities do not operate on patients who specify that they will not be able to attend follow-up visit. You do not need to worry about any deficiency as long as you attend follow-up visits.

Weight loss surgeries have been performed approximately for 45 years. Previously, open surgery technique was used. Thanks to modern surgical methods, closed (laparoscopic) surgery techniques can be used. All obesity surgeries specified above can successfully be performed with closed method. Thus, convalescence is shorter, pain is very minimal and there is almost no scar in postoperative period. ​