Gastrin 17 is mainly secreted by G-cells in the gastric sinus and can reflect to some extent the state of gastric acid secretion and the function of gastric sinus mucosal cells, and is a means of assessing gastric function by serum. The low value of only 0.6 pmol/L may be caused by excessive secretion of gastric acid, which can be related to H. pylori infection, gastric ulcer, and atrophic gastritis. Common causes 1, H. pylori infection: H. pylori infection generally has no obvious symptoms, but if the infection induces related diseases, the symptoms of related diseases will appear. Its metabolism produces a variety of enzymes and metabolites, etc., which can directly damage and destroy the mucosa, and the result may be low when checking gastrin; 2, gastric ulcer: inflammatory defects have occurred in the gastric mucosa, and naturally low levels of gastrin 17 will occur. The main symptom of gastric ulcer is burning pain in the stomach, as well as loss of appetite, bloating, weight loss, etc.; 3, atrophic gastritis: atrophic gastritis belongs to a type of chronic gastritis, characterized by the reduction or atrophy of the intrinsic glands of the stomach. Mainly manifested as epigastric discomfort, loss of appetite, belching and other gastrointestinal symptoms. Note healthy people occasionally improper diet and lifestyle may also lead to abnormal gastrin 17, it is recommended to review after adjusting diet and lifestyle.