If a person's stool is black, the likeliest reasons are that they have eaten certain foods or that there is bleeding in their gastrointestinal tract. For a person who has no other symptoms and who suspects that foods are to blame, there should be no cause for concern.

When should I be concerned about black stool?

Black stool can be caused by a serious or life-threatening disease or condition of the gastrointestinal tract, such as a bleeding ulcer. It is important to contact your health care provider if you develop black stools, bloody stools, rectal bleeding, or a color change in your stools.

What is wrong with you if your poop is black?

Most cases of black stools are from eating black foods or iron supplements. Stool that is black due to blood indicates a problem in the upper GI tract. Blood in the stool can be detected through a stool test. See your healthcare provider right away if you have black stool along with pain, vomiting, or diarrhea.