Bariatric Surgery is a surgery to reduce the size of the stomach or to reduce the absorption of the stomach, which can be called surgery to treat obesity because there is a hormone in our stomach that causes appetite. When we reduce the size of the stomach, the part containing this hormone is also removed. When this hormone decreases, it results in reduced appetite.
Who can undergo bariatric surgery?
- Individuals over 18 years old
- Those with obesity, defined as a BMI greater than 32.5
- Those who have not succeeded in losing weight through other methods
- Those without contraindications for surgery or psychiatric disorders
“Bariatric surgery is considered an appropriate method to achieve good treatment outcomes for better health. Doctors will assess whether the patient is ready and safe for surgery to ensure effective results without any concerning diseases or complications.”
Understanding the term “Obesity” – What is it really?
Obesity (Morbid Obesity or Adiposity-based chronic disease: ABCD) is a medical condition characterized by excessive fat accumulation in the body to a degree that may severely affect health, leading to a shorter lifespan, health problems, and risk of various complications. The diagnosis of obesity is based on calculating the Body Mass Index (BMI), which is calculated by dividing “weight” (in kilograms) by height (in meters) squared, according to the formula BMI = weight (Kg) / [height (m)]².
BMI Criteria and Evaluation
|
Less than 18 |
Underweight |
| 18.5 – 22.9 | Normal weight |
| 23.0 – 24.9 | Overweight |
| 25.0 – 29.9 | Obese |
| 30 and above | Severe obesity |
BMI Calculation Example
Mr. Somchai, 35 years old, weighs 62 kilograms and is 170 centimeters tall, and Ms. Somying, 28 years old, weighs 55 kilograms and is 155 centimeters tall. Who has a better BMI?
Mr. Somchai: BMI = 62 kg / [(1.70 x 1.70) m] = 21.45
Ms. Somying: BMI = 55 kg / [(1.55 x 1.55) m] = 22.89
Conclusion: Both Mr. Somchai and Ms. Somying have a normal body proportion and the lowest risk of complications.
What causes obesity?
- Genetics
- Eating behaviors
- Exercise habits
- Age and gender
- Emotional and psychological disorders
- Certain diseases and medications
Effects of obesity on the body
- Type 2 diabetes
- High blood pressure
- High blood cholesterol
- Heart disease, especially coronary artery disease
- Fatty liver disease and fatty liver hepatitis
- Snoring and sleep apnea
- Osteoarthritis
- Infertility
- Certain types of cancer
Detailed BMI Interpretation
BMI < 18.5 “Underweight”
Individuals with BMI below the standard level are at high risk of malnutrition, leading to fatigue and low immunity. Exercise combined with a high-protein diet helps strengthen muscles and provides sufficient nutrients for organ repair.
BMI 18.5 – 22.9
Individuals with BMI in the standard range have the lowest risk of obesity-related complications. It is recommended to maintain this BMI consistently by calculating BMI during annual health check-ups.
BMI 23.0 – 24.9 “Overweight”
Individuals with BMI above the standard range have a risk of obesity-related complications. They should control body fat by choosing high-protein foods, exercising regularly, resting adequately, and increasing daily activities that burn energy to reduce fat to a normal range.
BMI 25.0 – 29.9 “Obese”
Individuals with BMI significantly above the standard range have a high risk of obesity-related complications. They should urgently control body fat by adopting a healthier diet, exercising regularly, avoiding snacks, drinking at least 8 glasses of water daily, resting adequately, and regularly monitoring BMI during weight control.
BMI 30.0 > “Severe Obesity”
Individuals with BMI far above the standard range have the highest risk of obesity-related complications. They should see a doctor for medication to control blood sugar, change eating habits to healthy foods, reduce fat intake, exercise regularly, rest adequately, drink at least 10-12 glasses of water daily, and regularly monitor BMI during weight control.
Limitations of BMI
Since BMI calculation to estimate body fat has limitations related to gender, age, and muscle mass in some individuals, BMI results may vary as follows:
- Women tend to have higher body fat than men because female hormones promote fat storage more easily, so BMI in men may reflect about 15% body fat, while in women it can be up to 25% of total body mass.
- Older individuals tend to have more fat accumulation than younger ones.
- Athletes with high physical training have higher muscle mass than fat, resulting in higher BMI that does not necessarily indicate excess fat.
Why do conventional weight loss methods often fail?
In reality, disciplined exercise and controlled eating are the most important for weight loss. However, research shows most people lose only 5–10% of their body weight because the body adapts to a starvation-like state, making diet control ineffective. Some even suffer health problems due to excessive dieting and exercise. Moreover, over 50% of those who lose weight through diet and exercise regain the weight within 2 years.
For those with very high body weight, exercising like the general population is difficult because of fatigue and higher risk of injury. Therefore, the most important factor for safe and appropriate weight loss is consulting specialized doctors with expertise and experience to plan effective treatment and provide continuous follow-up.
Benefits of bariatric surgery for obesity treatment
When weight loss by conventional methods is not possible, bariatric surgery is a safe option. This method is internationally standardized and serves as a starting point for obese patients to lose weight. After surgery, patients can easily control their weight through exercise and dietary behavior control. The hospital has a specialized medical team ready to provide consultation and treatment planning for effective and long-term results. Typically, patients lose about 1-2 kilograms per week initially and can resume normal exercise within 1 month. After weight loss, existing chronic diseases may improve or resolve.
What are the methods of bariatric surgery?
Bariatric surgery is mainly divided into two methods:
1. Laparoscopic Sleeve Gastrectomy (LSG)
This is a laparoscopic surgery using automatic stapling devices to reduce the stomach size to a tube-like shape similar to a sleeve. This limits the amount of food intake per meal and reduces appetite-regulating hormones produced by the removed part of the stomach.
2. Laparoscopic Roux-en-Y Gastric Bypass (LRYGB)
This is a laparoscopic surgery using automatic stapling devices to divide the stomach into a smaller food-receiving part and connect it to the middle part of the small intestine. This limits food intake and reduces nutrient absorption, as well as decreases stimulation of appetite-regulating hormone secretion.
Comparison table of bariatric surgery methods
|
Control Item |
LSG | LRYGB |
| Excess weight loss | 50-60% within 18-24 months | 60-80% within 12-18 months |
| Treatment of associated diseases | ++ | +++ Usually, most medications can be stopped |
| Amount of food intake after surgery | 4-5 bites/meal | 2-3 bites/meal |
| Malnutrition after surgery | + | +++ May require some vitamin supplements |
| Duration of surgical effect | 2 years (depends on patient compliance) | 2 years (depends on patient compliance) |
| Common postoperative complications |
Acid reflux |
Dumping Syndrome |
Considerations for choosing bariatric surgery method
To achieve good treatment outcomes that meet patient needs and minimize impact on their quality of life, decisions are made collaboratively between the patient, medical team, and multidisciplinary professionals. Since the best results are achieved with the first surgery, patients with a BMI over 50 kg/m² are recommended to consider gastric bypass surgery if there are no contraindications, rather than sleeve gastrectomy.
Importance of patient preparation before bariatric surgery
Before undergoing bariatric surgery, patients must undergo health assessments by specialized medical teams and multidisciplinary professionals in various fields, including:
- Endocrinologist or obesity specialist to assess risk factors and causes of obesity, and treat related internal diseases such as diabetes, hypertension, and high cholesterol.
- Gastroenterologist or liver specialist to evaluate fatty liver and fatty liver hepatitis through abdominal ultrasound and liver tissue scan (Fibroscan), and provide treatment if inflammation is present.
- Respiratory specialist for snoring and sleep apnea assessment, including Sleep Test and evaluation for the need of CPAP (Continuous Positive Airway Pressure) device. If required, treatment should start at least 6-8 weeks before surgery.
- Upper gastrointestinal endoscopy to assess esophagitis from acid reflux, Helicobacter pylori infection, and other anatomical abnormalities related to surgery outcomes.
- Nutritionist consultation to modify eating behaviors by reducing high-calorie foods (total daily calories should not exceed 800-1200), reducing rice, starch, and fat intake, increasing fiber, and choosing lean meats.
Additional consultations with other specialists such as psychiatrists, dermatologists, or orthopedic surgeons may be necessary for comprehensive evaluation and treatment before surgery.
Patients will be advised to start appropriate exercise based on their physical limitations and health, focusing on resistance training to build muscle and aerobic exercise to increase calorie and fat burning.
During preparation, patients are encouraged to lose about 5-10% of excess weight to reduce surgical risks and complications and improve postoperative weight loss outcomes.
Postoperative care after bariatric surgery
In the early postoperative period, patients must adjust their eating behavior by eating only at meal times and stopping when feeling full. They should focus on protein and meat-based foods, avoid rice and starch, limit total daily calories to 800-1200, avoid drinking water during meals and about 1 hour before and after meals, but drink enough water between meals, aiming for at least 2500-3000 milliliters per day.
Snacking between meals and consuming alcoholic beverages should be strictly avoided.
Advantages of bariatric surgery
- Small surgical wounds
- Short recovery time after surgery
- Patients can resume normal exercise immediately (depending on suitability)
- Specialized medical team with expertise and direct experience collaborates with multidisciplinary teams to support and plan treatment with maximum safety
Recommendations
- If a patient requires CPAP for sleep apnea before surgery, they must continue using it until the doctor advises otherwise.
- Patients should attend regular follow-up appointments as scheduled. The medical team will monitor weight loss trends, complications, and malnutrition after surgery, and adjust medications for related diseases as symptoms improve.
- Female patients are advised to use contraception to prevent adverse effects of weight loss on fetal development.
- After 2 years or more post-surgery, most patients can eat more, and some weight regain may occur. It is crucial to maintain proper eating habits and adequate exercise, along with continuous follow-up with the medical team to sustain good long-term results.
