Possible causes of vomiting once eating include: physiological causes, cold and fever, liver disease, digestive tract diseases, etc. 1. Physiological reasons: the sensitivity of the gastrointestinal tract increases when the patient is nervous or emotionally excited, which may cause the phenomenon of vomiting when eating. It is also possible that the HCG level in a woman’s body rises after pregnancy, resulting in pregnancy reactions such as nausea, vomiting and loss of appetite. 2. Cold and fever: If the patient has a cold and fever in winter, he or she will suffer from loss of appetite, nausea and vomiting, and indigestion. 3. Liver disease: Patients suffering from liver disease have a lot of destroyed liver cells, poor bile secretion, not easy to digest fat, cholesterol and other substances, and may vomit when eating. 4. Digestive diseases: patients with gastritis, gastric ulcer and other diseases have damaged gastric mucosa, gastrointestinal tract dysfunction, insufficient digestive function, and may also vomit after meals. If the symptoms can not be relieved in time, it is recommended that patients seek medical attention in time to avoid delaying the condition.