Stool color can only initially distinguish the condition of the digestive system, but you can not rely on stool color alone to judge the condition of the whole body. Normal people’s stool color should be light yellow, brown and other colors, by observing the color of the stool, you can initially distinguish whether there are abnormalities in the digestive system. First, if the color of the stool has recently become black or red, it may be due to conditions such as gastrointestinal bleeding, but it may also be due to recent blood products such as pig’s blood or taking certain medications (such as bismuth). Secondly, if the color of the stool is potter’s clay, it may be due to bile duct obstruction associated with bile duct stones and biliary tract tumors. The above scenarios are only preliminary judgments by abnormal stool color, which may be due to digestive system diseases, but may also be due to physiological factors, and cannot be used as a means of confirming the diagnosis. At the same time, simply relying on the color of the stool is not able to distinguish the condition of the entire body, because other systemic diseases, such as urinary system, cardiovascular system, etc., usually do not lead to a change in the color of the patient’s stool. To sum up, patients who have recently experienced abnormal stool color need to consult a doctor in time to clarify the specific cause. Patients who have normal stool color but experience discomfort also need to consult a doctor in a timely manner and not rely solely on stool color for self-diagnosis.