DOB value is the result of carbon 13 breath test, the normal range is between 0~4dpm, out of the range suggests the infection of Helicobacter pylori. The carbon 13 breath test is a quick, non-invasive test for detecting the presence of H. pylori infection in the human body, with an accuracy rate of more than 95%. The normal range of DOB is 0~4dpm, within the normal range is negative, mostly indicates that there is no H. pylori infection, if the DOB value is greater than 4dpm, it is positive. H. pylori is associated with the development of peptic ulcer, gastritis, gastric cancer, etc. Abdominal pain, abdominal distension, weight loss, anemia, black stools and other symptoms can occur, so it is recommended that further gastroscopy to clarify whether there are gastric lesions. If DOB is positive, it is recommended to consult the gastroenterology department of regular hospitals in time. Daily attention should be paid to dietary hygiene and regular sterilization of tableware, etc.