The stool is thick at the beginning, and then as thin as squeezing toothpaste, mainly considering physiological factors and pathologic factors. 1. Physiological factors: when the patient takes high protein food for a long time, consumes too little vegetables and fruits, and eats too little, resulting in too little intestinal content and slow gastrointestinal peristalsis, this situation will occur. 2. Pathological factors: when the patient suffers from gastroenteritis, due to gastrointestinal peristalsis obstacles leading to abnormal excretion of intestinal contents, the above situation will also occur. When the patient has gastrointestinal tumors, the tumor occupying the place will also cause the stool shape to change and the above situation will occur. In addition, if the stool is thick at the beginning and then as thin as squeezing toothpaste, there may be other reasons. It is recommended to go to the hospital in time, complete the examination and clarify the cause of the disease, and then give targeted treatment or therapy under the guidance of the doctor.