The stomach cannot usually be made smaller naturally, but it can be made smaller through surgery. 1. The volume of the stomach changes with the amount of food eaten. If you eat a lot, the volume of the stomach will increase, and if you eat less, the volume of the stomach will decrease. However, the volume of the stomach is constant and usually does not change. If you usually eat a lot of food, for example, if you often overeat, you should pay attention to improving your eating habits and eat less and more often. 2. Some patients who have too large a stomach volume and are overweight can have their stomach capacity reduced by taking gastric surgery if necessary. However, even after gastric surgery, it is still necessary to pay attention to adjust the diet and living habits, and increase the amount of exercise to avoid causing obesity again.