Smelly farts all the time may be related to constipation, improper diet, functional dyspepsia, organic lesions of the gastrointestinal tract and so on. 1. Constipation: the patient’s stools accumulate in the intestines for a long time and can not be discharged, which will be mixed with the intestinal flora and fermentation, and the phenomenon of smelly farts will occur. 2. Improper diet: often eat gas-producing food, such as potatoes, sweet potatoes, etc., will generate a large amount of gas in the gastrointestinal tract, which will lead to the symptom of smelly farts. 3. Functional dyspepsia: it can cause the gastrointestinal peristalsis of patients to slow down, and the food residues and feces will stay in the gastrointestinal tract for a long time, which will produce a large amount of odor gas after mixing with the intestinal flora, and then manifest smelly farts. 4. Organic lesions of the gastrointestinal tract: such as gastritis, gastric and duodenal ulcer and other diseases, can affect the digestive function, once indigestion occurs, the symptoms of smelly farts. There are many other reasons that cause patients to have smelly farts all the time, if the symptoms are serious or continue to not get better, it is recommended to go to the hospital in a timely manner, after clarifying the cause of the disease, under the guidance of the doctor for targeted treatment.