The reasons for the very smelly exhaust all the time are mainly seen in the following points: 1, dietary factors, mainly due to eating more gas-producing and heavy-smelling foods, such as white radish, scallions, soybean products, and meat products. Due to this type of food in the gastrointestinal tract digestion, absorption process, will produce more gas, and heavy smell, and lead to exhaust very smelly. 2, intestinal infection, due to a large number of bacteria, viruses infect the intestinal tract, resulting in damage to the mucosa of the intestine, inflammatory cell infiltration, food in the gastrointestinal tract in the digestive process, inflammatory substances, and the role of pathogenic bacteria will produce a large amount of gas, and the phenomenon of exhaust very smelly. 3, Indigestion, mainly due to intestinal flora dysbiosis leading to indigestion, the balance of intestinal flora is broken, pathogenic bacteria become the dominant flora, food in the role of pathogenic bacteria will produce a lot of gas, and the phenomenon of very smelly exhaust. 4, intestinal tumors, mainly refers to malignant tumors, due to tumor erosion led to a large number of intestinal mucosa, tissue necrosis, which will produce a large amount of gas, resulting in the phenomenon of very smelly exhaust.