Farting stinks every afternoon may be caused by physiological factors such as eating irritating foods and high protein foods, or it may be caused by intestinal flora imbalance, indigestion, and disease factors such as ulcerative colitis. 1. Physiological factors: if you often eat garlic, onions and other flavorful foods or often eat pork, beef and other foods with high protein content, these foods will be broken down into irritating gases in the intestinal tract, the body may appear in the afternoon every day, the performance of the exhaust stinks, which is a normal physiological phenomenon. 2. Intestinal flora imbalance: when intestinal flora imbalance, harmful bacteria will appear in the intestinal tract, and the food or feces in the intestinal tract will produce foul-smelling gas after the fermentation of the harmful bacteria, which will be manifested as the above symptoms. 3. Dyspepsia: When patients suffer from dyspepsia, gastrointestinal peristalsis will slow down, and if food stays in the gastrointestinal tract for a long time, foul-smelling gas will be produced in the intestines, which will lead to the symptom of foul-smelling exhaust in the afternoon every day. 4. Other: the patient every afternoon exhaust odor may also be related to ulcerative colitis, gastric cancer, amoebic dysentery and other diseases. It is recommended to consult a doctor in time to clarify the cause of the disease under the guidance of a professional physician.