Nausea after meals is not necessarily a precursor of stomach cancer, but may also be caused by gastroesophageal reflux, inflammation of stomach, gastric ulcer and other conditions. 1. Gastroesophageal reflux: it is due to the reflux of food from stomach into esophagus, which causes nausea and vomiting, heartburn, acid reflux and other uncomfortable symptoms. 2. Inflammation of the stomach: the common clinical manifestations of gastritis are epigastric pain, feeling of fullness, nausea, anorexia, etc. Gastroscopy is usually needed to clarify the situation. 3. Gastric ulcer: Helicobacter pylori infection, drugs, acute trauma, bad dietary habits and other factors can lead to gastric ulcer, which often manifests as stomach pain, fullness and bloating after meals, stomach discomfort, loss of appetite, nausea after meals and so on. It should be noted that stomach cancer may also cause nausea after meals, so it is necessary to go to the hospital in time to improve the gastroscopy, which can also determine whether there are obvious occupying lesions in the stomach, and be able to diagnose whether there is gastric cancer or other stomach diseases in time. It is recommended to take the initiative to consult a doctor if there is any abnormality, so as not to delay the condition.