Every day at 3 or 4 p.m., you will feel upset stomach may be caused by dietary factors, hunger, duodenal ulcer and so on. 1. Dietary factors: may be due to the midday ate too much greasy or spicy stimulating food, the stomach caused by the stimulation, and food accumulation in the stomach is not timely digested, thus causing the symptoms of upset stomach. 2. Hunger: If you eat early at noon, at 3 or 4 p.m., the stomach has been emptied, and it is easy to feel the stomach hungry, thus causing symptoms of stomach upset. 3. duodenal ulcer: because at three or four o’clock in the afternoon, the stomach is in the empty cavity state, if itself suffers from duodenal ulcer, when the stomach acid secretion is too much, it will cause stimulation of the ulcer surface, causing abdominal pain. If discharged when dietary factors or hunger caused, need to promptly go to the hospital, clear diagnosis and take treatment.