Dark bowel movements can be red, brown, gray or black. The cause of the stool darkening will determine the color; however, most dark stool appears black.
Bilirubin, which is found in bile, undergoes many chemical changes as it passes through the digestive tract. These changes can account for the color of stool, which is usually light or dark brown for normal processes or dark green when chemical changes have happened rapidly.
Duodenal, gastric and peptic ulcers can all cause stools to become black.
Tumors in the abdomen and intestines may cause intestinal bleeding leading to tarry, black stool. These tumors can also cause blockages keeping bilirubin from making it into the stool, which will cause gray, clay-like bowel movements.
When bleeding occurs in the digestive tract, for any reason, stool will turn black due to the chemical changes to the hemoglobin flowing into the intestinal tract. If the bleeding is occurring in the lower intestines, than stools will appear red in color.
High intake of iron from ingesting foods like beets or medicines such as bismuth subsalicylate or Pepto Bismol will harmlessly darken stool.
What Does Blood in Your Stool Mean?
It can be a scary thing to look at the toilet paper or into the bowl and see blood on or in...
Bowel Problems in Dogs
Bowel problems in dogs run the gamut, with symptoms ranging from little or no fecal output to severe diarrhea. If your dog...
What Are the Causes of Dark Stool?
Dark stool is caused by upper GI tract bleeding. Generally, we get concerned when we see blood or red-tinged feces, but dark,...
What Does Mucus in the Stool Mean?
It is not unusual to see small amounts of mucus in your stool, but there are times when it can be an...
What Does White or Pale Stool Mean?
Stool should appear light brown and have little odor, and its appearance is an indicator of digestive health. Diseases, chronic conditions and...
Are Black Stools a Symptom of Colon Cancer?
Colon cancer, also known as colorectal cancer, is a cancer that occurs in the large intestines. According to the Mayo Clinic, colon...
Is Dark Brown a Normal Color for Stool?
Dark-brown colored stools are in the range of normal colors for human stools. Stool color is influenced by a person’s diet and...
How Can I Tell If Blood is in My Stool?
Finding blood in the toilet after excreting waste can indeed be shocking. However, the appearance of blood in the toilet after using...