Stool Color Changes: What Does It Mean?

Changes in the stools may occur for several reasons.

Bowel movements are usually light to dark brown in color, and there is moderate variation among individuals concerning stool color, quantity, and form. When these changes in stool do occur, it can mean that there may be an illness affecting the gastrointestinal (GI) tract or the entire body.

The stool (also called feces, bowel movement, or poop) color is most commonly brown. When stool color changes, a person, parent, or caregiver often becomes concerned.

• The presence of bilirubin in the bile (a breakdown product of the hemoglobin in red blood cells that are normally destroyed after a useful life cycle of several weeks) is generally responsible for the brown stool color.
• Bilirubin concentration can vary the color of the stool from light yellow to almost black.
• Changes in the chemical structure of the bilirubin can cause stool to turn green or yellow.
• Yellow stool also may occur if the stool is dilute or if there is a reduction in the amount of bilirubin produced by the liver.
• Bacteria and digestive enzymes in the intestine can act on the bilirubin and change its color.

Most bowel movement to bowel movement changes in color have little meaning. However, some changes, particularly if the changes are consistent over time and not present in only one stool, may mean something needs to be investigated.

A normal healthy stool is smooth, sausage-shaped, well-formed, and easy to pass. It should not cause discomfort or pain during bowel movements. However, it can vary in size, shape, and smell among individuals, but there are general characteristics that define a healthy bowel movement. These include:

• Color: Normal stool is typically medium to dark brown in color, which is attributed to the presence of bile and bilirubin. These compounds, originating from the liver and gallbladder, mix with food during digestion, resulting in the familiar brown color.
• Shape: A healthy stool usually has a log-like shape, reflecting its formation within the intestines. Any significant deviation such as fragmented or small pellets may indicate an underlying issue.
• Consistency: The consistency of a healthy stool should range from firm to soft, and it should be easy to pass without straining.
• Duration: A healthy bowel movement should be easy to pass and take only a minute or so. Prolonged time spent in the washroom may indicate issues with digestion or bowel health.
• Frequency: It is normal to have a bowel movement anywhere from three times a day to three times a week. The key is consistency in your routine.
• Smell: While stool naturally has an odor, it should not be excessively foul-smelling. Extremely bad odors can be a sign of a digestive issue or infection.

Examples of healthy stools:

• Medium brown, sausage-shaped, soft but firm: This is a classic example of a healthy stool. It’s easy to pass and holds its shape without being too hard or too soft.
• Slightly softer, with some texture: A stool that is soft but still has some texture and form is also considered healthy. This may be common for individuals who consume a high-fiber diet.
• Brown, smooth, and consistent: Even if the stool is a bit softer or firmer on some days, as long as it remains consistent and passes easily, it’s generally considered healthy.

An unhealthy stool refers to any bowel movement that deviates from the norm in terms of color, shape, or consistency. While occasional variations are common, persistent changes warrant attention. Here are some key indicators of unhealthy stools:

• Consistency: Stools that are consistently hard, lumpy, or watery can indicate digestive issues. Hard, pellet-like stools may suggest constipation, while watery stools can indicate diarrhea.
• Color: Unhealthy stool colors can vary and may include pale or white stools, which can indicate problems with the liver, gallbladder, or pancreas. Bright red stools may signal bleeding from hemorrhoids, while black stools could indicate bleeding in the upper gastrointestinal tract.
• Smell: Foul-smelling stools can be a sign of malabsorption disorders or digestive issues.
• Frequency: Sudden changes in bowel habits, such as persistent diarrhea or constipation, can be concerning and may indicate an underlying health condition.
• Shape: Abnormal shapes like pencil-thin stools can be a sign of issues in the colon.

Unhealthy stool colors:

• Pale or white: These colors can indicate issues with the liver, bile ducts, gallbladder, or pancreas. It may be due to insufficient bile reaching the stool, potentially caused by conditions affecting these organs.
• Bright red: Often caused by bleeding from hemorrhoids, bright red stools can also indicate lower gastrointestinal bleeding.
• Black: It can signify bleeding in the upper gastrointestinal tract, potentially from conditions such as ulcers or gastritis.
• Yellow: May indicate liver or gallbladder issues, digestive problems, or malabsorption disorders such as celiac disease or pancreatic cancer.
• Green: While usually harmless and related to diet, persistent green stools can sometimes indicate digestive issues.

Examples of unhealthy stools:

• Bright red stools: Could be a sign of hemorrhoids or lower gastrointestinal bleeding including hemorrhoids, diverticulosis, or colorectal cancer.
• Black or tarry stools: Indicate bleeding in the upper gastrointestinal tract, potentially from ulcers or gastritis
• Yellow stools with foul smell: Can signal liver or gallbladder issues, digestive problems, or malabsorption disorders.
• Pale or white- or clay-colored stools: Often linked to liver, gallbladder, or pancreas issues, these indicate insufficient bile in the stool due to conditions such as hepatitis, cirrhosis, or gallstones.
• Watery or liquid stools (diarrhea): May indicate infections, food intolerances, or digestive disorders such as irritable bowel syndrome (IBS) or inflammatory bowel disease (IBD).
• Hard, pellet-like stools: Often a sign of constipation, which can result from insufficient fiber intake, dehydration, or certain medications.
• Greasy, floating stools: May suggest malabsorption issues where the body isn't properly absorbing fats. Conditions such as celiac disease or chronic pancreatitis can cause this.
• Thin or ribbon-like stools: Can indicate bowel obstruction or colorectal cancer.
• Large, bulky stools: Often associated with malabsorption or excessive intake of certain foods.
• Other unusual colors: Yellow, green, orange, or white stools can signify underlying conditions and warrant discussion with a health care provider.

Unhealthy stools can indicate a range of health issues, from dietary problems to serious diseases. Monitoring stool characteristics such as color, consistency, shape, and frequency can provide valuable insights into one’s digestive health. If persistent changes in stool occur, it is important to seek medical advice for proper diagnosis and treatment.

In most cases, feces color changes are not symptoms of any disease.

Changes in stool color may be due to the following:

• Diarrhea (may cause yellow-green stools)
• Some foods (beets, Jell-O, Kool-Aid, licorice, green leafy vegetables)
• A few over-the-counter (OTC) and prescription medications
• Diseases affecting the liver, pancreas, and intestines
• Bleeding in the intestinal tract

The most common medications that change the color of the stool are the drugs that turn the stool black and include iron and bismuth (contained in Pepto-Bismol and Kaopectate). Nevertheless, a large number of other drugs have been associated with changes in the color of stool to black or other colors. Practically, the importance of this fact is that any new drugs or dietary supplements need to be considered as the cause of any change in stool color.

The Bristol Stool Chart is a medical tool that classifies human feces into seven categories based on their shape and consistency. It helps health care providers diagnose and manage various gastrointestinal conditions.

Seven types of poop:

Type I: Separate hard lumps, like nuts, which are difficult to pass and indicate constipation.

• Appearance: Small, hard, and round lumps that resemble nuts or pebbles.
• Consistency: Very hard and difficult to pass.
• Indications: Often indicates severe constipation. The stool has spent a long time in the colon, causing excessive water absorption and resulting in a hard texture.

Type II: Sausage-shaped, but lumpy stools, indicating constipation.

• Appearance: Lumpy and sausage-like.
• Consistency: Firm and chunky, with noticeable lumps.
• Indications: Suggests constipation, though it is less severe than type I. It can be uncomfortable to pass and indicates a slow bowel movement.

Type III: Sausage-shaped stools with surface cracks, considered ideal.

• Appearance: Sausage-shaped with surface cracks.
• Consistency: Firm but not as hard as type I or type II.
• Indications: Normal, but may hint at mild constipation due to slightly slower transit time through the colon.

Type IV: Sausage or snake-like stools that are smooth and soft, considered ideal.

• Appearance: Smooth, soft, and sausage- or snake-like.
• Consistency: Soft and easy to pass.
• Indications: Suggests healthy bowel function and adequate fiber and water intake.

Type V: Soft blobs with clear-cut edges, trending toward diarrhea.

• Appearance: Soft blobs with well-defined edges.
• Consistency: Soft and easy to pass.
• Indications: This type can be normal, especially if defecation occurs multiple times a day. It indicates a higher moisture content in the stool.

Type VI: Fluffy pieces with ragged edges and mushy stools, indicating diarrhea.

• Appearance: Fluffy with ragged edges.
• Consistency: Mushy.
• Indications: Suggestive of mild diarrhea resulting from rapid transit through the colon, impeding adequate water absorption.

Type VII: Watery stools with no solid pieces, entirely liquid, indicating diarrhea.

• Appearance: Entirely liquid with no solid form.
• Consistency: Watery.
• Indications: Indicates severe diarrhea, often associated with infection or illness.

Changes in stool color alone do not cause symptoms. The underlying cause of the change in stool color, texture, or form is responsible for any symptoms.

If stool passes through the intestine too quickly, there might not be enough time for bile to be digested and broken down to provide the normal brownish stool color. Normally, bacteria in the intestine chemically change bile to a greenish-brown color. It takes time for the bile to fully revert in the intestine and become brown again, and if the transit time is short, for example, when a person has diarrhea, the stool remains green-colored.

Green stools may be a normal variant. A diet rich in green vegetables, especially spinach, or iron supplements also may cause green poop, though iron often turns stool black.

There are a variety of reasons why stool will be yellow, greasy, and foul-smelling. It can be due to the intestine's inability to digest and absorb fat, which may result from diseases of the intestinal lining (such as celiac disease and cystic fibrosis), the inability of the pancreas to manufacture adequate digestive enzymes (such as with chronic pancreatitis or pancreatic cancer that blocks the pancreatic duct), or inadequate bile being delivered to the intestine (such as in cancer of the liver or bile ducts that are blocked). The yellowness, greasiness, and foul smell are due to the undigested fat.

The most common cause of bright red-colored stool in adults is bleeding from hemorrhoids. One of the most concerning causes is bleeding in the gastrointestinal tract. Although this usually presents with dark, black stool, it can also cause bright red blood. This will require urgent evaluation by a health care provider. In infants, the most common cause is an anal fissure or tear in the tissue surrounding the anus.

Other causes for bright red blood in the stool may be more serious, such as:

• Infections of the intestines
• Inflammatory bowel disease (Crohn's disease, ulcerative colitis)
• Diverticular bleeding
• Tumors
• Arteriovenous malformations (abnormal communications between arteries and veins in the wall of the intestine that rupture)

Brisk bleeding from the ulcer in the esophagus, stomach, or duodenum also may cause stools to be red instead of black if there has not been enough time for the red blood cells to be digested.

Red food coloring and beets can also give a reddish hue to the stool.

Orange stools can result from certain dietary choices, such as consuming foods rich in beta-carotene (carrots, sweet potatoes, pumpkins) or artificial food coloring. Taking certain supplements or medications, such as antacids containing aluminum hydroxide, can also lead to orange-colored stools.

Sometimes, orange stools may indicate medical conditions involving the liver, bile ducts, or digestive disorders such as irritable bowel syndrome (IBS), celiac disease, or Crohn’s disease. If orange stools are accompanied by symptoms such as abdominal pain, changes in stool consistency, fatigue, weight loss, jaundice, or fever, it is important to seek medical advice for a thorough evaluation.

Black stools are a worrisome symptom because they may be due to a large amount of bleeding into the digestive system, most often from the upper GI tract including the esophagus, stomach, and duodenum. Red blood cells are broken down by digestive enzymes in the intestine and turn the stool black. These stools tend to be tar-like (sticky) and foul-smelling. This can be a medical emergency; black tarry stools should not be ignored.

Blood from nosebleeds, dental procedures, or mouth injuries can be swallowed and may be the cause of black stool, but the amount of bleeding usually is not substantial enough to do this.

Light-colored stools or clay-colored stools are often seen with diseases of the liver or bile ducts. What’s the link between pancreatic cancer and stool color? The pale stool may be caused by pancreatic cancer that blocks the bile ducts. Lack of bile causes stool to lose its brown color and leaves it appearing pale.

Maroon-colored stools are often due to bleeding in the GI tract. The source of bleeding for red stools is the upper GI tract (esophagus, stomach, duodenum), while the colon is the source of bright red blood. Maroon stools, which are caused by partial digestion of the blood in the intestine often arise from the small intestine (jejunum, ileum) and proximal colon, but the color also depends in part on how rapidly the blood travels through the intestines. The faster the stool moves through the GI tract, the brighter red the color. This can be an emergency.

In children with intussusception, where one portion of the intestine telescopes into another part, causing a temporary obstruction, stools may be described as currant jelly in color and consistency.

The mucus in the stool may be normal, and it may cover segments of formed feces. However, it also can occur in people with inflammatory bowel disease or cancer. Mucus associated with blood and/or abdominal pain should not be ignored and requires medical attention. People with irritable bowel syndrome (IBS) also can have mucus in the stool.

Most stool floats because it contains an excessive amount of gas. By itself, it is normal and has little meaning. Changes in diet can lead to stool that floats, but as an isolated symptom, no action needs to be taken, and often it resolves spontaneously. The stool does not float because of an increased amount of fat. (Fat in stool causes oil droplets in the toilet bowl.)

Any condition that causes increased amounts of gas to form in the intestines theoretically may lead to floating stool, especially in conditions where there is malabsorption of nutrients such as lactose intolerance, celiac disease, cystic fibrosis, and short bowel syndrome.

People have their own size, shape, and stool consistency. It is the change in stool pattern that matters more than the absolute size and shape of the stool. Narrow stool, sometimes called pencil-thin, may occur occasionally and is of no concern. People with irritable bowel syndrome (IBS) may develop thinner stools.

Nevertheless, a person with "normal" stools that has a new change in the diameter, length, and width (caliber) of the bowel movement should consult his/her health care professional. This may be a sign of a narrowed or scarred colon, perhaps due to a tumor, but the health care professional may want further information about accompanying symptoms or tests.

It is not unusual to have two or even three stools in the morning. The first stool will usually have a more solid form because it has been in the colon (where water is absorbed) the longest. The second stool will be looser, and if there is a third stool, it will be the loosest. Another change in stool form that often requires evaluation is the development of looser or firmer than normal stools. At one end of the spectrum is constipation and at the other end is diarrhea, but even if the change does not reach these levels, consistent, milder changes in either direction need to be evaluated.

Aside from black, red, or maroon stools that may mean bleeding is a possibility, and require urgent assessment and treatment, most color changes are not an emergency. The significance is determined based on other symptoms that might be present.

Women who are pregnant often note changes in their bowel patterns. The stool can turn black because of iron and vitamin supplements. Iron can also turn stool greenish. As the uterus enlarges and increases pressure within the pelvis, constipation may occur and hemorrhoids can develop and cause blood in the stool.

If there is no underlying problem, stool color changes are often due to changes in the diet and will resolve in a couple of days. If this is not the case and changes persist, it is appropriate to contact your health care professional and seek medical attention.

Contact your doctor if you have stool color changes and associated symptoms such as vomiting, diarrhea, fever, or abdominal pain.

It is important to remember that every person is different and changes in bowel habits, be it color, size, frequency, or consistency (hard or soft), may be normal for one person or a sign of a potential problem for another.

Most often, people will contact their primary care health care professional with questions about the color of their stool. These include health care professionals who care for infants and children. Depending upon the cause of the stool color change, certain specialists may need to be involved. For example, for red or black stool due to bleeding, a gastroenterologist may be needed to perform an endoscopy to look for a bleeding source in the stomach or intestine.

Gastroenterologists are specialist that helps manage other diseases of the intestinal tract, including Crohn's disease, pancreatitis, and celiac disease, which can cause color changes because of poor absorption of nutrients from the diet.

Diagnosing the cause of stool color changes involves a comprehensive evaluation that typically includes a detailed medical history, physical examination, and specific diagnostic tests. One of the primary diagnostic tools used is stool analysis.

Stool analysis: This laboratory examination of a fecal sample helps diagnose various conditions affecting the digestive tract. The test can provide information about the presence of infection, inflammation, malabsorption, and other gastrointestinal conditions.

Components of stool analysis include:

Macroscopic examination:

• Color: Observing the color of the stool can provide initial clues. Normal stool is typically brown due to the presence of bile. Deviations from this color can indicate different conditions:
  • Green: May indicate rapid transit through the intestines or the ingestion of green foods or certain medications.
  • Black: Can suggest upper gastrointestinal bleeding (melena) or ingestion of iron supplements or bismuth-containing medications.
  • Clay-colored: May indicate bile duct obstruction.
  • Red: Suggests lower gastrointestinal bleeding, which could be due to conditions such as hemorrhoids or colorectal cancer.
  • Yellow: May indicate malabsorption, often seen in conditions such as celiac disease or chronic pancreatitis.
• Consistency: Evaluating the texture (such as watery, soft, or hard) helps in diagnosing conditions such as diarrhea or constipation.
• Odor: While subjective, a particularly foul-smelling stool may indicate infection or malabsorption.

Microscopic examination:

• Parasites and eggs: Identifying parasitic infections, such as Giardia and Entamoeba histolytica, through microscopic examination of stool samples.
• Fat content: High levels of fat (steatorrhea) may indicate malabsorption conditions, such as pancreatic insufficiency or celiac disease.
• Leukocytes: The presence of white blood cells in stool can indicate inflammation or infection, as seen in conditions such as inflammatory bowel disease (IBD) or bacterial infections.
• Red blood cells: Microscopic bleeding may be identified through the presence of red blood cells in the stool, indicating conditions such as IBD or colorectal cancer.
• Chemical tests: Various chemical tests may be performed to detect specific substances in the stool, such as occult blood (blood that is not visibly apparent), which could indicate gastrointestinal bleeding.
• Cultures: Stool cultures may be conducted to identify bacterial or fungal pathogens that could be causing gastrointestinal infections.

Stool analysis is a valuable diagnostic tool in gastroenterology and can provide important insights into various gastrointestinal conditions. However, it's essential to remember that stool analysis is just one part of the diagnostic process, and its interpretation should be combined with other clinical information for accurate diagnosis and appropriate management.

In most cases, a diagnosis, if any, cannot be made by stool color alone.

The patient and the doctor need to consider other symptoms, past medical history, dietary changes, and medications to help decide what has caused the stool to change color. A physical examination will be important to help decide the significance of the stool color.

The stool may be tested to look for blood, fat, or infection. Blood tests may be necessary depending on the clinical situation. Depending on the color change, it may be necessary to evaluate the pancreas, liver, or GI tract.

Treatment for changes in the stool depends on the symptoms and condition causing the changes.

Black stool

The treatment for black stool varies depending on the underlying condition or reason. If the dark-colored poop is caused by certain foods, stopping those foods will make the condition go away.

Black stool causes may include peptic ulcers. If that’s the case, certain medications, such as proton pump inhibitors or PPI, may be prescribed by the doctor. You may also be advised to stop eating spicy foods. Your doctor may perform a procedure, such as an endoscopy (a procedure in which a flexible tube-like instrument with a camera and light source is used to view the inside of the gut), to treat a bleeding ulcer.

Depending on the extent of blood loss, you may need supplements or blood transfusion. If you are taking certain medications, such as aspirin or NSAIDs, your doctor may ask you to stop taking them.

You may need antibiotics or anti-protozoal medicines if the bleeding is due to certain infections.

Surgery and other appropriate therapy may be needed in case of variances and cancer.

What are black specks in stool?

Black specks in stool can have several potential causes, ranging from benign dietary factors to more serious medical conditions.

Dietary causes:

Foods:

• Consuming certain foods can lead to the appearance of black specks in stool.
• Common culprits include blackberries, blueberries, dark leafy vegetables, and foods with dark pigments or dyes.
• Sometimes, undigested parts of food such as seeds, skins, or other fibrous materials can pass through the digestive tract and appear as black specks in the stool.

Medications and supplements:

• Iron supplements and medications containing bismuth, such as Pepto-Bismol, can cause the stool to appear darker or black and may also create black specks.

Gastrointestinal bleeding:

Bleeding from the esophagus, stomach, or upper part of the small intestine can result in black or tarry stools, known as melena. Conditions causing such bleeding may include:

• Peptic ulcers: Ulcers in the stomach or upper small intestine can bleed, causing dark stools.
• Gastritis: Inflammation of the stomach lining can lead to bleeding.
• Esophageal varices: These are swollen veins in the esophagus that can bleed.
• Mallory-Weiss tears: These are tears in the esophagus due to severe vomiting.

Intestinal conditions:

• Diverticulosis: Small pouches (diverticula) in the colon wall can sometimes bleed, causing dark specks in stool.
• Inflammatory bowel disease (IBD): Conditions such as Crohn's disease or ulcerative colitis can cause bleeding in the intestines, leading to black specks in the stool.
• Parasitic infections: Some parasitic infections can cause black specks in stool. These specks might be the bodies or eggs of the parasites.
• Fungal infections: Overgrowth of Candida (a type of yeast) in the intestines can sometimes cause black specks in stool.

If black specks persist for more than a few days alongside symptoms such as abdominal pain, diarrhea, unintended weight loss, or rectal bleeding, it's vital to consult a doctor. Seeking medical attention is crucial for identifying the underlying cause and determining appropriate treatment, especially if there are concerns about gastrointestinal bleeding or parasitic infections.

Green stool

Green stools are generally harmless and will resolve on their own. If you want to treat green stools, there are several ways you can potentially return your stool to its standard shade.

If you've been eating large amounts of green vegetables, they are likely the cause. Reducing your spinach intake may return your stools to their normal color. Similarly, if you've started taking iron supplements, lowering your dose will likely help.

For short-term intestinal problems like gastroenteritis, your priority should be to keep yourself hydrated and comfortable. The illness should resolve by itself in a few days to a week and your stools will return to normal.

If your stomach problems continue for longer than a few days or you're having trouble staying hydrated, you should reach out to your physician for medical treatment.

Mucus in stool

Depending on the diagnosis, your doctor may advise medical treatment or simple home-based care. If it is an infection, your doctor will prescribe the necessary antibiotics and medicine to manage the symptoms.

Some conditions like mild food poisoning will only require you to drink more fluids and a diet change.

A clear diagnosis will help you and your doctor to find the best cure for your condition.

Oily stool (steatorrhea)

To treat steatorrhea, your underlying condition must be treated by a health care provider.

You may require pancreatic enzyme replacement therapy if you have exocrine pancreatic insufficiency.

• If your intestines are not getting enough bile, you might benefit from a bile acid replacement, such as Ursodiol (ursodeoxycholic acid).
• You may require additional treatment to avoid complications of fat malabsorption. Long-term fat malabsorption can result in severe fat-soluble vitamin deficiencies (A, D, E, and K).

Treatment for various levels of malnutrition and its complications could be required.

• Is undigested food in stool bad? Undigested food in stool is a common occurrence, especially when consuming high-fiber foods. In most cases, it is a sign of normal digestion and does not indicate any underlying health issues. However, in some instances, it can be a symptom of certain medical conditions.
• Can you see liver flukes in stool? Liver flukes are not typically visible in stool samples. The eggs of liver flukes, which are the primary diagnostic indicator of infection, are usually microscopic and require specialized laboratory tests to detect them.
• What color is a stool with a bad liver? Stools associated with a bad liver can often appear pale, clay-colored, or gray. This discoloration occurs because the liver's impaired function affects bile production and release, which is crucial for giving stool its normal brown color.
• Is dark stool a problem? Dark stools (black or tarry stools) can be a sign of a variety of issues, ranging from harmless food or medication side effects to more serious medical conditions.