Causes shown here are commonly associated with this symptom. Work with your doctor or other health care professional for an accurate diagnosis. Mayo Clinic does not endorse companies or products. Advertising revenue supports our not-for-profit mission.

There are many different reasons why you might experience rectal bleeding. The causes of rectal bleeding can vary from common and mild conditions to more severe and rare conditions that need immediate medical treatment. There are certain foods that can make your poop an unusual color. You can have green, yellow and even black stool. This can happen for a variety of reasons — having too much bile during digestion, having a medical condition like inflammatory bowel disease or celiac disease, being on antibiotics, or even just eating foods with strong color pigments. Often, blood can make your stool look very dark and almost black.

We include products we think are useful for our readers. If you buy through links on this page, we may earn a small commission. Rectal bleeding usually refers to bleeding from the anus, rectum, or colon, all of which are the final portions of the digestive tract. In most cases, bright red blood indicates bleeding in the lower colon or rectum, while darker red blood is a sign of bleeding in the small bowel or upper colon. Very dark or black-red blood is often associated with bleeding in the stomach or other organs in the digestive system.

We include products we think are useful for our readers. If you buy through links on this page, we may earn a small commission. Rectal bleeding has many causes and can occur as the result of a weaker or abnormal area along your digestive tract. According to the Cleveland Clinic , hemorrhoids are the most common cause of rectal bleeding.