Black stool must be bleeding?

Black refers to black stool, black stool is not necessarily bleeding, black stool is bleeding, usually need to be judged in combination with the actual situation.

If the patient recently eat a large number of pig heart, pig liver, duck liver and other iron-rich foods, easy to cause iron ion content in the stool increased, resulting in stool color change, this time generally not bleeding. If the patient in addition to black stool, but also stomach distension, loss of appetite, abdominal pain and other clinical symptoms, and gastrointestinal dysfunction, this time is usually bleeding. Because bleeding will cause the divalent iron in the blood to decompose into trivalent iron through digestive juice and be discharged through stool, black stool phenomenon occurs.