Farting before defecation can be caused by physiological factors, dietary reasons, indigestion, intestinal diseases and other factors. 1. Physiological factors: When defecating in a squatting or sitting position, the intra-abdominal pressure can be increased due to changes in the body, providing a certain amount of pressure for the discharge of stools, and the gas is usually easier to be discharged under the effect of pressure. 2. Dietary reasons: excessive intake of radish, onion, garlic and other gas-producing foods in the daily diet can cause more gas accumulation in the intestines, and the gas will be discharged first in the stool. 3. Indigestion: Impaired gastric tolerance diastolic function and delayed gastric emptying can cause food to accumulate in the gastrointestinal tract for too long, and a large amount of gas is easily produced by the fermentation of intestinal flora, which stimulates the production of the urge to have a bowel movement, and the gas will be discharged first when having a bowel movement. 4. Intestinal diseases: When polyps and tumors occur in the intestinal tract, it is easy to cause intestinal obstruction and narrowing of the intestinal lumen, which can lead to obstruction of the discharge of stools as well as the accumulation of food and fermentation to produce gas, which can be discharged first during defecation. If you have a bowel movement that produces gas first, you need to consult a doctor in time for a clear diagnosis and treatment. Timely and appropriate treatment will help to alleviate your discomfort as soon as possible.