Blood in your stool. The cleansing of our body is a complicated process, and it lasts every day without stop. Your stool is a waste product, but it can tell a lot about your body and health issues. If there are any problems with your digestive system or liver, the stool test is the first way to diagnose an illness. Jaundice is also on the list of problems that can be diagnosed by your stool. And the most important symptom is blood in your stool. You should go to a doctor as soon as you noticed any signs of blood.