Stomach bloating after lunch may be caused by dietary factors, indigestion, gastritis and so on. 1. Dietary factors: it may be due to eating too much spicy and stimulating food or overeating during lunch, which leads to acute gastric mucous membrane damage, thus causing gastric distension. 2. Indigestion: If the usual activity is relatively low, coupled with a poor diet, it is easy to lead to a decline in digestive ability, food in the stomach for a long time, it is easy to cause gastric distension. 3. Gastritis: after eating lunch, because of food stimulation leads to increased secretion of gastric acid, the gastric mucosa caused by stimulation, thus causing gastric distension, gastric acid, heartburn and other symptoms. After lunch bloating pain can be appropriate to the stomach massage and hot compresses, if the symptoms continue to be unrelieved, the need for timely consultation, active treatment.