What Do the Different Poop Colors and Shapes Mean?

Here's what stool color and consistency changes could mean

stool
Peter Cade/Getty Images

Although you may not pay much attention to your stools, looking at them regularly can help you pick up on variations in color, shape, and texture that are typical for you and persistent changes that should be investigated.

Here's a description of some of the different types of poop, from stool that is yellow, green, pale, dark, or red to poop that is pebble-shaped or accompanied by mucus. Keep in mind that you should always talk to your doctor about new or concerning symptoms.

What Does a Normal Bowel Movement Typically Look Like?

While it's normal for bowel movements to vary from day to day depending on a number of factors including what you eat and drink, they should generally be formed and some shade of brown. Stools should leave the body with little straining or discomfort, have a toothpaste-like consistency, and look more like a banana than a pencil. You shouldn't see mucus or blood.

Yellow Stool

Having yellow poop may simply mean that you’ve been eating foods high in sweet potatoes, carrots, turmeric, or yellow food coloring.

If the onset is recent, yellow stool can also be a sign of an intestinal infection, particularly if it’s accompanied by diarrhea, fever, flu-like symptoms, and stomach cramps. Giardiasis, a small intestine infection caused by the parasite Giardia lamblia, can also lead to yellow stool.

In addition, people with gastroesophageal reflux disease (GERD) and those taking medication for GERD sometimes have yellow poop.

In some cases, yellow poop may signal the presence of excess fat in the stool, a condition that may be caused by anything that disrupts the intestinal lining (such as celiac disease) or disorders affecting the pancreas, liver, or gallbladder. This type of stool usually looks greasy and may be foul-smelling, frothy, or float in the toilet bowl.

Green Stool

Seeing green stool in the toilet bowl can be alarming, but there are some common reasons why it occurs. Eating lots of leafy vegetables like kale or spinach can give stool a greenish color, but it's normal and shouldn't stop you from getting your fill of these antioxidant-rich foods. Food coloring, including green, purple, and blue dye, and iron supplements can also turn feces an emerald color.

Besides the obvious foods and dyes, any food, supplement, or condition that speeds up intestinal activity can also lead to green stool. Recent changes in your diet can also do it. In women, green stool is more likely to occur at certain times during pregnancy. Find out the many possible causes of green poop in adults and babies.

Stool That Sinks Quickly

Although normal stool shape and frequency varies widely from person to person, if your stool quickly sinks, you may not be getting enough fluids or fiber in your diet. This stool is often dark because it stays in the intestines longer.

Floating Stool

Occasionally having stool that floats is often nothing to be concerned about. Most commonly, floating stool happens when you have increased gas that mixes into stool, causing it to float. It can be caused by anything from carbonated drinks, beans, and sugary foods to conditions like irritable bowel syndrome (IBS).

If you notice that your stool floats consistently, it could also be a sign that you're not absorbing fat properly. Called steatorrhea, this type of stool often has odor, sticks to the side of the bowl, or is difficult to flush away. Find out about these and other reasons why you may have floating stool.

Small, Pebble Stool

Stool that comes out in small pieces rather than long and smooth is sometimes called pebble or pellet stool. Fiber forms a gel in the intestines when it is fermented by bacteria in the colon and combined with water. If there is a lack of fiber holding stool together, it may be shaped like small pebbles.

Upping your intake of fiber may help, by slowly increasing your intake to the recommended 20 to 35 grams daily. Foods like brown rice, quinoa, flaxseeds, beans, and pears are just some of the foods that can help. Learn more about the causes of small, pebble stool.

Loose Stool

Loose stool lasting a couple of days or less is common and usually isn't serious. It can be triggered by recent changes in your diet, too much fructose (a sugar found in honey and many soft drinks and processed foods), and many different foods, supplements, and medication.

While eating something that upsets your digestive system can result in loose stools, another common cause is a gastrointestinal infection (sometimes known as the "stomach flu"). Learn more about what loose stool could mean and when it's time to call your doctor.

Infrequent Stool

If your bowel movements are dry, difficult to pass, or infrequent (occurring less than three times a week), you may have constipation. While certain medications and conditions can result in constipation, for many people, it's a lack of dietary fiber. Legumes and raspberries are just some of the foods that can help constipation.

If constipation is ongoing (lasting over two weeks) or if it's accompanied by symptoms like nausea, vomiting, pain in your abdomen, you should see your health care provider. 

Mucus in Stool

Although mucus is commonly found in stool, you normally don't notice it because it tends to be clear. A thick, jellylike substance, mucus lubricates your intestines (protecting them from stomach acid, bacteria, viruses, or fungi) and makes bowel movements slippery and easy to pass.

If you start seeing mucus in your stool or notice that the mucus is white or yellow, mention it to your health care provider at your next visit. While it doesn't necessarily mean that something is wrong, you want to report any change in bowel habits to your doctor. In some cases, it could indicate inflammation or irritation in the intestinal wall and signal an underlying health issue.

Pencil Thin Stool

Excessive straining when you are on the toilet can result in stool that is long and thin. Bearing down causes the anal sphincter to contract and narrows the opening of the anus. Stool that is squeezed through the narrowed opening is thin.   

Consistently thin stools, however, could signal a medical problem. Any condition that obstructs the bowels, such as benign rectal polyps, hemorrhoids, prostate enlargement, or colon, rectal or prostate cancer, could cause pencil thin stool, so you should see your health care provider if you regularly notice that you have pencil thin stool.

Pale Stool

Bile salts in the intestines give stool its characteristic brown color. Stool that is light-colored (either pale, white, grey, or clay-colored) could indicate a lack of bile in stool. If you notice that your stools are white, clay-colored, or chalky grey, you should see your doctor. A blockage of the bile ducts from gallstones or a condition affecting your gallbladder, liver, pancreas, or liver are some causes of decreased bile output.

Pale or light-colored stool may also be shiny or greasy, floating, and foul-smelling, due to undigested fat in the stool. 

Certain medications such as bismuth subsalicylate (Pepto-Bismol®, Kaopectate®) or anti-diarrheal drugs may also result in light-colored stool. Stool may become temporarily pale after a barium enema test.

Undigested Food in Stool

Seeing undigested food in your stool on occasion typically isn't anything to worry about. Certain plant foods such as corn and grape skins, for instance, often appear in recognizable pieces in stool because we lack the enzymes needed to digest certain components of plant cell walls.

Eating more slowly and chewing each bite thoroughly can help. If you see undigested food in your stool regularly, however, and it's accompanied by other changes in your bowel habits like diarrhea or stomach cramps, it's a good idea to bring it up with your healthcare provider.

Bright Red Stool

Bright red stool can be caused by beets, cranberries, or tomato juice or soup, or red food coloring (e.g. red or grape Kool-Aid or other drink mixes, gelatin, ice pops, red candy, red frosting, and red licorice). Red medicines such as Amoxicillin may also turn stool red.

If there is blood in stool, the color depends on where it is in the digestive tract. Blood from the upper part of the gastrointestinal tract, such as the stomach or esophagus, will look dark by the time it exits the body as a bowel movement. Blood that is bright red, on the other hand, is more likely to come from bleeding in the lower gastrointestinal tract, such as the large intestine or rectum, due to conditions such as arteriovenous malformations, hemorrhoids, anal fissures, ulcerative colitis, diverticulosis, or colon cancer.

Blood in stool doesn't always appear bright red. Blood may be also present in stool but not visible, called "occult" blood. Tests such as the fecal occult blood test may be used to detect hidden blood in stool.

Black or Dark Stool

Certain foods, supplements, and medications can temporarily turn stool black, such as:

  • Bismuth subsalicylate (Pepto-Bismol®, Kaopectate®)
  • Iron supplements
  • Activated charcoal supplements
  • Dark foods such as black licorice, blueberries, Oreo cookies, blackberries, grape juice, or blueberries

Stool can also appear darker with constipation. Dark green stool from bile that hasn't had time to break down may look black in certain lighting.

Stool that is almost black, dark, or tarry with a thick consistency may indicate bleeding in the upper part of the gastrointestinal tract, such as the stomach or esophagus. Medical conditions that can cause dark, tar-like stool include duodenal or gastric ulcers, esophageal varices, Mallory-Weiss tear, and gastritis.

If you experience this type of stool and it is not from food or supplements, you should see your doctor as soon as possible.

A Word From Verywell

Most day-to-day variations in the appearance of your stool have to do with what you eat or drink. While the biggest concerns are unusual poop colors or shapes that persist, consult your doctor if you're concerned about your stool or notice any changes in your bowel habits. 

If your stool is bright red, black, or pale, consistently thin or pencil-like, loose or watery, or accompanied by mucus or pus, or if you have additional symptoms like abdominal pain, be sure to see your doctor right away.

Sources:

Ip S, Sokoro AA, Buchel A, et al. Use of fecal occult blood test in hospitalized patients: survey of physicians practicing in a large central Canadian health region and Canadian gastroenterologists. Can J Gastroenterol. 2013 Dec;27(12):711-6.

Disclaimer: The information contained on this site is intended for educational purposes only and is not a substitute for advice, diagnosis or treatment by a licensed physician. It is not meant to cover all possible precautions, drug interactions, circumstances or adverse effects. You should seek prompt medical care for any health issues and consult your doctor before using alternative medicine or making a change to your regimen.

Continue Reading