The constant hunger feeling is related to chronic gastritis, duodenal ulcer, hyperthyroidism, diabetes, etc. First of all, patients with chronic gastritis will be stimulated by inflammation, thus leading to excessive secretion of gastric acid. Patients will be decomposed and emptied by gastric acid faster after food intake, so patients’ stomachs will often feel hungry. Secondly, duodenal ulcer is a common peptic ulcer, which will not only cause excessive secretion of gastric acid, but also cause painful sensation when gastric acid then causes irritation history to the mucosa. Some people will then mistake the painful sensation as being caused by hunger in the stomach when it occurs. Finally, hyperthyroidism and diabetes are hypermetabolic diseases that cause a lot of energy to be consumed in the body because of hyperfunction and sympathetic excitement. They are often accompanied by a feeling of hunger and an increase in the number of bowel movements, which requires treatment to improve the disease.