FM/CFS/ME RESOURCES - What Your Bowel Movements Are Telling You


Search Site 
Disability Attornies
Find A Doctor
Drugs Used In FM & CFS/ME
In-Person Support Groups

Archived Poll Results
Candles of Hope
CMP Info.
Family and Friends
Financial Help
Letter To Loved Ones
Living With FM & CFS/ME
Newly Diagnosed
Rate Your Meds  -  Results
Recommend Doctor
Researchers Spotlight

Take Quiz
Quiz Winners
Patient Surveys

What Your Bowel Movements Are Telling You

It may not be a topic typically talked about at the dinner table or a cocktail party, but most people are actually somewhat obsessed with it. And with good reason: The state of your gastro-intestinal tract (as well as the quality and quantity of its output) is a great barometer of the health of your body.

"The GI tract is a processing unit that metabolizes all of the nutrients you take in and eliminates all of the body's waste," explains Dr. Amy Foxx-Orenstein, president of the American College of Gastroenterology. "What comes through it is reflective of how well or how ill the body is."

Hard and Dry

The amount of time it takes for the food you eat to make its way through the gastro-intestinal system and exit into the toilet will have an impact on the consistency of your stool.

"Intestinal transit averages 40 to 45 hours from when you eat to when it comes out," says Foxx-Orenstein. If it stays in the GI tract for longer than that, fluid is re-absorbed into the body and the stool becomes harder and dryer. Certain medications, like blood pressure drugs, antidepressants, histamines and medications, can slow down the GI tract.

Constipation, which has a myriad of causes, will lead to harder, drier stools (since you're going less often, your stool will stall in the system and the fluid re-absorbed). For some people, a diet high in dairy can be a cause of constipation, so if you are experiencing problems going (and have dry, hard-to-pass stool when you do finally go), it is worth reducing your dairy intake for a week or two to see if that helps. And being dehydrated can also lead to this problem because if the body is lacking in water, it will draw it, and conserve it, from wherever it can find it.

Little Lumps

"An ideal stool looks like a torpedo—it should be large, soft, fluffy and easy to pass," says Foxx-Orenstein. But when conditions are less than ideal, the stool may become more like little deer pellets. Again, transit time may be part of the issue because slow-moving stool will lose fluid, making them less fluffy and lumpier.

A lack of fiber in the diet may also to be to blame. Beware if you're following a weight-loss plan (such as Atkins) that focuses on increasing protein and decreasing carbohydrates, since that can leave you with a diet that's low in fiber. And since fiber holds on to fluid, a lack of it will lead to harder, pellet-like poops that may be more difficult to pass.

Too Liquid

Your body secretes about eight liters of fluid during the course of a day, from the stomach, salivary glands and pancreas, to help your food get broken down and make its way through the digestive system. Under normal, healthy conditions, the majority of that fluid is absorbed along the way, resulting in those sought-after soft, fluffy stools.

But if food passes through too quickly, there isn't enough time for all of that liquid to absorb, and the stool emerges in a too-soft state. The reasons for such super-quick transit could include a sudden increase in fiber in the diet, or a bacterial or viral infection.

"When there is an infection, the body produces toxins which cause water to be released," says Dr. Michael Farber, director of the Executive Health Program at Hackensack University Medical Center. "Things move through very quickly through your system because the body wants to get rid of them."

In traditional Chinese medicine, loose stools, abdominal bloating, lack of energy, and poor appetite can be signs of a condition known as spleen qi deficiency. It doesn't necessarily involve your actual spleen, but it is linked to tiredness and weak digestion brought on by stress and poor diet.

Pencil Thin

Thin may be the preferable state for many things such as: figures, cell phones, television screens, but when it comes to bowel movements, thin is definitely not a good thing. Specifically, thin stools could be an indicator of colon cancer, or its precursor, polyps in the colon.

"Whenever you have mass in the colon that creates blockage, anything that needs to be pushed past that mass will become thinner," Farber says. "If you are seeing thin stools on a consistent basis, that it something you should have looked at by your doctor."

Looking Pale or Gray

Normal stool can come in a range of colors (influenced by what you eat and what medications you take, among other factors). But if your stool has an unhealthy hue, particularly if it's pale or grayish in tone, you could have problems somewhere along your digestive tract. The liver excretes bile to help break down fats in the food you eat, and that bile also adds color to the stool.

But if there's a blockage in the liver, or in the tubes through which the bile travels, the stool might take on a too-pale appearance. Also, if you are suffering from a pancreatic disorder, the stool might look gray because it will be lacking the color imbued by the digestive enzymes produced in that organ.

Bright Red

Your first instinct upon seeing red-colored stool in the toilet would probably be to panic. But before you speed-dial your doctor, think about what you ate several hours ago, if it was beets or bright red popsicles, that might be the culprit for creating those colored stools.

But if it's obviously a streak of red blood in the stool, in the toilet, or on the toilet paper, then it's a given that you're bleeding somewhere inside. There's still not necessarily any reason to panic, the cause could be something as benign as a hemorrhoid or just a small fissure caused by straining to go.

When there is blood in stool, the color depends on where it is in the digestive tract. Blood from the upper part of the digestive tract, such as the stomach, will look dark by the time it reaches exits the body as a bowel movement. Blood that is bright or dark red, on the other hand, is more likely to come from the large intestine or rectum.

Conditions that can cause blood in the stool include hemorrhoids, anal fissures, diverticulitis, colon cancer, and ulcerative colitis, among others. Blood in stool doesn't always appear bright red. Blood may be also present in stool but not visible, called "occult" blood. A test called the Fecal Occult Blood Test is used to detect hidden blood in stool.

Dark Stool

Stool that is almost black with a thick consistency may be caused by bleeding in the upper digestive tract. The most common medical conditions that cause dark, tar-like stool includes duodenal or gastric ulcer, esophageal varices, Mallory Weiss tear (which can be linked with alcoholism), and gastritis.

Certain foods, supplements, and medications can temporarily turn stool black. These include:

  • Bismuth (e.g. Pepto bismol)
  • Iron
  • Activated charcoal
  • Aspirin and NSAIDS (which can cause bleeding in the stomach)
  • Dark foods such as black licorice and blueberries

Dark stool can also occur with constipation. If you experience this type of stool, you should see your doctor as soon as possible.

Yellow Stool

Yellow stool can indicate that food is passing through the digestive tract relatively quickly. Yellow stool can be found in people with GERD (gastroesophageal reflux disease). Symptoms of GERD include heartburn, chest pain, sore throat, chronic cough, and wheezing. Symptoms are usually worse when lying down or bending. Foods that can worsen GERD symptoms include:

  • peppermint
  • fatty foods
  • alcohol
  • coffee
  • chocolate

Yellow stool can also result from insuffient bile output. Bile salts from the liver gives stool its brownish color. When bile output is diminished, it often first appears as yellow stool. If there is a greater reduction in bile output, stool lose almost all of its color, becoming pale or grey. If the onset is sudden, yellow stool can also be a sign of a bacterial infection in the intestines.

Floating Stool That Smells

Those ideal torpedo-like poops should sink when they hit they hit the toilet. But when the body isn't properly absorbing fat from the food you eat, it ends up being excreted in your stool. The result: stool that's yellowish in color, greasy in consistency, foul smelling, and that floats in the toilet.

Certain medical conditions, like celiac disease, can cause these malabsorption problems. And since essential nutrients could also be lost along with the un-absorbed fat, it's important to see your doctor if you experience this problem. These fatty, smelly stools are also one of the more unpleasant side effects of eating foods that contain Olestra (the faux fat found in some chips and other fried snacks) or of taking the weight loss drug Xenical or its over-the-counter cousin, Alli.

Green Stool

The liver constantly makes bile, a bright green fluid, that is secreted directly into the small intestine or stored in the gallbladder. Bile is needed to absorb fats and fat soluble vitamins. It also helps to soften stools and is responsible for giving stools their characteristic brown color.

As bile makes its way through the intestines, it progressively changes color from green to yellow to brown, due to the action of bacteria in the large intestine on the bile salts. Green stool often indicates that food has passed through the intestines faster than normal (called decreased bowel transit time), before it could be changed from green to brown. Diarrhea decreases bowel transit time, so any condition that causes diarrhea can result in green stool.

Other causes of green stool include:

  • Laxative use
  • Antibiotic use
  • Medication side effects
  • Food poisoning
  • Celiac disease
  • Ulcerative colitis
  • Crohn's disease
  • Malabsorption
  • Irritable bowel syndrome
  • Bacterial overgrowth
  • Infectious diarrhea - especially salmonella and giardia
  • Traveler's diarrhea
  • Cancer

Foods and supplements that can cause green stool include:

  • Chlorophyll
  • Iron supplements
  • Algae

You May Also Like

Return to top of page


  • Dr. Amy Foxx-Orenstein, American College of Gastroenterology.

  • Sally Wadyka, What Your Bowel Movements Are Telling You About Your Health, Health Topics: Digestive Health,

  • Dr. Michael Farber, director of the Executive Health Program at Hackensack University Medical Center.

  • Cathy Wong, Stool - Healthy and Unhealthy Stool,
Return to Top