Hunger at 3-4 pm every day is caused by irritable bowel syndrome, stomach fire, and hyperthyroidism. There are various manifestations of irritable bowel syndrome, and some people have hyperactive bowel movements as the main manifestation, which are more likely to occur when they are emotionally stressed or under stress. In the afternoon, 3-4 pm is in a more stressful state, some people will be triggered by the onset of the disease, thus appearing hunger performance. Most people with high stomach fire have hyperactive gastric motility, so they are more likely to experience hunger, which occurs within a few hours after food intake at noon because the stomach has been emptied of food. Hyperthyroidism is a hypermetabolic disease, mainly due to excessive secretion of thyroid hormones, which leads to faster metabolism and excessive consumption of fat and protein in the body.