Biochemical Mechanisms and Risks of "Small Stomach" Surgery: The Regulatory Effects of Sleeve Gastrectomy on the Hypothalamic Feeding Center

"Sleeve gastrectomy," medically known as laparoscopic gastric reduction surgery or sleeve gastrectomy, is an important treatment for morbid obesity. The basic procedure involves using a linear cutting and closing device under laparoscopic guidance to continuously remove the gastric body and fundus from the antrum to the angle of His. This process creates a tube-like structure in the remaining stomach, significantly reducing its volume.

This surgery not only reduces the amount of food entering the body, but its deeper mechanism lies in the removal of most of the endocrine cells in the stomach, leading to a significant decrease in appetite after surgery. To understand this principle, we need to understand the mechanism by which human appetite is generated: human eating behavior is controlled by the feeding center in the hypothalamus. The feeding center contains two reciprocally inhibitory centers, namely the "hunger center" and the "satiety center".

When the hunger center is excited, a person experiences a strong desire to eat; conversely, when the satiety center is excited, appetite decreases. There are two main physiological factors that trigger hunger: a decrease in blood sugar levels and a reduction in the volume of gastrointestinal contents. After gastric reduction surgery removes a large portion of the stomach, its capacity becomes extremely small. Even a small amount of food intake can cause the remaining stomach wall to expand, rapidly stimulating satiety signals, activating the satiety center, and suppressing appetite.

According to clinical literature, patients can lose an average of 70% of their excess weight in the first year after sleeve gastrectomy. Compared with other complex weight loss surgeries, this procedure is relatively less technically demanding, simpler and safer, and has a relatively milder impact on postoperative nutritional status.

However, it is crucial to be aware of the limitations and risks associated with this surgery. First, the surgery permanently alters the normal structure of the body's organs; the removed stomach cannot be restored. Post-operative complications may include bleeding at the surgical margin, leakage, and gastric stenosis. Furthermore, if the patient does not fundamentally change their unhealthy eating habits after surgery, the remaining "small stomach" may slowly expand again under long-term mechanical expansion, leading to weight loss failure.

Therefore, the medical community generally does not recommend "small stomach" surgery as the first-line method for weight loss. The ideal approach remains scientific weight loss through dietary restriction, correcting unhealthy lifestyle habits, and increasing physical activity. Surgical treatment should only be considered when obesity has not improved after trying various conventional weight loss methods, and the patient has serious obesity-related diseases such as hypertension or diabetes, faces significant exercise risks, and has a BMI (Body Mass Index) greater than 32 kg/m².

The decision to undergo surgery requires extreme caution, marking a significant shift from lifestyle interventions to invasive medical treatments. For most overweight and mild to moderately obese individuals, understanding the scientific principles of energy metabolism and cultivating a lasting exercise habit are the best ways to achieve long-term, stable, and lifelong health.