Having a bowel movement is a critical part of digesting the food we eat. Stool formed by the large intestine is the body’s way of getting rid of waste.
While you should talk to your doctor about any concerns, changes in poop color and consistency could show what is happening inside your digestive system.
Rocks and Pebbles
Poop that is hard and shaped like tiny rocks or pebbles is likely just a sign of constipation . You can still be considered constipated even if you are able to pass a small amount of stool.
The large intestine helps to concentrate waste by absorbing water. If muscle contractions in the large intestine are not working properly, waste left in the colon becomes even more concentrated, resulting in harder stool.
“One of the most common concerns I hear from patients is worry about the change of poop color,” says Dr. Linda Lee . The color of stool is impacted by the foods you eat and the kind of bacteria living in your colon.
“There are a lot of food colorings added to what we eat and drink, so of course the color of your stool is then going to change,” says Lee. “When I perform a colonoscopy, I can actually tell what color the beverage was they used to take the prep.”
A change in the color of stool is usually not cause for concern, unless it appears to be black or bloody, which could signal other problems with the digestive system.
Black and Tarry
The most common cause of black and tarry poop is from taking iron supplements or a medication containing bismuth, such as Pepto-Bismol. However, it could mean you’re losing blood somewhere in your gastrointestinal tract, such as in the stomach or small intestine.
Oily or Greasy Stools
If you have poop that appears oily, has a greasy consistency and is difficult to flush, it could be a signal that your body is not able to properly digest fat. The consistency changes could be caused by an infection, nutrients not being digested due to celiac disease or a problem with the pancreas, such as pancreatic cancer or pancreatitis.
Stool that is only occasionally very thin is not a cause for concern. It is likely due to muscle contractions in the large intestine as it helps to concentrate waste.
If there is a sudden and consistent change in your stool always being thin, it could mean there is a blockage in your colon, and you should see your doctor.