Can There Be Something Wrong With Your Stool?

Everybody poops! Stool, or feces, is what we call the waste material that leaves the body through the anus. We all must eat, and when we do, food is broken down. Our food goes through a lot of changes before it becomes stool, but it's not broken down fully; there is something left over.

Stool can often provide some big clues as to what's going on in the body, especially when something is going wrong.

A knit jacket with the applique of internal organs
Hiroshi Watanabe / Getty Images

What's in Stool

Stool is mostly undigested food, but it also contains bacteria, dead cells, and mucus. Digestion begins in the mouth as we chew our food. After food is swallowed, it travels down through the esophagus and into the stomach. Once in the stomach, digestive juices are mixed in and food is digested in earnest.

After the stomach breaks down the food, it moves into the small intestine. More digestive enzymes are added and nutrients are absorbed by small fingerlike hairs called villi.

By this time, many nutrients have been absorbed from food, and it continues along the digestive tract and into the large intestine. In the large intestine, water is absorbed. At the end of its trip through the large intestine and the digestive tract, stool passes into the rectum and then out of the anus as stool.

The Makeup of a Normal Stool

Normal stool is different from person to person. What's assuredly not normal is having too many loose stools (diarrhea) or too many hard stools (constipation). Striking a balance in the middle is the goal, with a stool that is soft and easily passed without any pain or discomfort. The number of stools per day is also variable, with a range of anywhere from 3 a day to once every 3 days. Every person needs to understand their own personal normal and talk to a physician when stools begin to move out of that normal range.

Things That Can Go Wrong

Unfortunately, plenty can go wrong in the digestive process. Any time there's a change in a normal stool pattern (think of differences in size, shape, frequency, and color), it's called a "change in bowel habits." Most of the time this will be temporary, but if it continues for 3 or more days, it's worth talking to the doctor about.


Waste material could move too quickly through the digestive system, which leads to diarrhea. Often diarrhea resolves on its own and the cause might not be known, but some of the many causes of diarrhea include:

  • Disease
  • Food intolerances
  • Functional bowel disorders
  • Infection (viral and bacterial)
  • Motility disorders
  • Parasites


Food can also move too slowly through the digestive tract, which could lead to constipation. Constipation could be temporary and resolve on its own but it could also be chronic. Some of the possible causes of constipation are:

  • Adhesions (scar tissue)
  • Bowel obstruction
  • Dehydration
  • Digestive diseases and conditions
  • Medication (such as pain medications)
  • Motility disorders
  • Other diseases (such as diabetes or thyroid disease)

Unusual Colors

Stool can come in a variety of colors and still be considered "normal" but if a change goes on for more than 3 days or can't be traced back to a food or a supplement, talk to a doctor. Some of the common reasons for differently colored stool are:

  • Red: Naturally and artificially colored foods can cause red stools.
  • Black: Green, black or purple foods as well as iron supplements can turn stool green.
  • Green: Green foods and iron supplements can be the cause.
  • Orange: Red or orange foods and some medications can cause this color.

Red Flag Symptoms

Blood in the stool. Blood in or on the stool could mean red or black stools. Blood in the stool is never normal, and should always be checked out by a doctor. If stools are black, tarry, and foul-smelling, this could also be from blood and should be discussed with a doctor right away.

Pale stool. Sometimes pale stool could be the after-effect of a barium test, in which case it might not be a cause for worry, but it could also be a result of a blocked bile duct. If there hasn't been a barium test recently, contact a doctor about pale colored stools.

Narrow stools. Narrow stools could be the result of a narrowing in the bowel, so it is a reason to make a call to a doctor.

Absence of bowel movements. Not having any stools for a while could mean a blockage, which tends to be more common in people with inflammatory bowel disease (and Crohn's disease in particular).

If any of these signs are accompanied by other symptoms such as abdominal pain or vomiting, seek medical attention immediately.

A Word From Verywell

We tend to think of stool as looking one particular way but there are all different sizes, shapes, and colors of stool. The idea is that a person's own brand of normal is individualized, and if stool starts to look as if it's outside that normal range, it could indicate that something is going amiss in the digestive process. In many cases, changes in stool will resolve on their own because they might be due to a change in diet or an illness, but when symptoms go on for 3 or more days, it's important to talk to a doctor. Blood in the stool is always a reason to see a doctor because it is not a normal occurrence and can be the result of many different diseases and conditions, some of which are serious.

9 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Amber J. Tresca
Amber J. Tresca is a freelance writer and speaker who covers digestive conditions, including IBD. She was diagnosed with ulcerative colitis at age 16.