You can’t eat grapes when you have an upset stomach. Although grapes are rich in vitamins and minerals, eating them when you have an upset stomach will aggravate the symptoms of stomach discomfort. Grapes are acidic food, which will stimulate the gastric mucosa to secrete a large amount of gastric acid after entering the stomach. Most stomach diseases (such as gastric ulcer and gastritis) are themselves caused by excessive secretion of gastric acid, so eating them can aggravate the condition. During the period of discomfort, try to eat a liquid diet and easy-to-digest food, such as millet porridge, corn porridge, egg custard, and so on. If the patient has vomiting, nausea and other symptoms can be suspended eating, after the symptoms are relieved can eat a small amount of food. If symptoms such as epigastric pain, fullness, nausea, vomiting, heartburn, acid reflux, etc. occur, it is necessary to go to the hospital in a timely manner, under the guidance of the physician to avoid delaying the condition.