If you eat too much hard food, too much greasy food, because these foods are difficult to digest in the stomach, they are discharged into the intestines with the stool before they are completely digested. Patients with indigestion usually have problems with digestion, insufficient power, slow gastrointestinal peristalsis can lead to food not being completely digested and absorbed, staying in the stomach for a long time, and discharged into the intestines without being completely broken up and digested in the stomach, and the small intestine can not completely digest and absorb the food before it is discharged from the body. Patients with gastrointestinal disorders have abnormal gastrointestinal functions due to excessive mental stress and excessive tension, and slow gastrointestinal peristalsis leads to incomplete digestion and absorption of food, resulting in undigested food residues in the stool.