Normal stools in the morning and unformed stools in the middle of the day may be caused by improper diet, irritable bowel syndrome, enteritis and other reasons. 1. Improper diet: eating hot pot and other spicy, stimulating food at noon, stimulating the mucous membrane of the gastrointestinal tract, resulting in faster peristalsis caused by the midday stools are not shaped. 2. Irritable Bowel Syndrome (IBS): The stress of studying and working in the morning is relatively high, and excessive busyness, anxiety, and overstress induce IBS, leading to unformed stools at noon. 3. Enteritis: Bacterial and viral infections in the intestinal tract lead to faster intestinal peristalsis, causing unformed stools at noon accompanied by abdominal pain, fever, etc. The stools in the morning are normal, but the stools in the middle of the day are unformed. If you have normal stools in the morning but not at noon, it is recommended that you consult a doctor in time to find out the cause of the problem and treat it as soon as possible.