It usually takes 24 hours for food to enter the body before it can be excreted. After entering the stomach, the food is completely emptied in about 2 to 4 hours. The food enters the intestinal tract where it is further broken down and digested to absorb the nutrients. After about 4-8 hours, the food is transformed into feces and stored in the sigmoid colon and rectum. However, it needs to be stored in a certain amount before it can stimulate the rectal sensory organs and induce a bowel movement. Within 24 hours after the food enters the body, a certain amount of feces is stored and a bowel movement occurs. When the body wakes up in the morning, the gastrointestinal peristaltic response occurs, and the speed of intestinal peristalsis increases because of the change in body position. Therefore, the food consumed on the first day is usually excreted in the early morning of the second day. However, the exact timing may vary depending on the intestinal peristalsis of each individual.