Black specks in stool may be due to undigested food, such as blueberries. However, they can also be a sign of internal bleeding or liver problems. In newborns, black stool may be meconium.

Daily factors such as diet or minor gastrointestinal distress can affect stool color. However, if stools turn black or have black specks for several days, a person should see their doctor to determine the cause.

In this article, we look at the causes of black specks in adult and baby stools, treatments, and when to see a doctor.

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Healthy bowel movements are normally a medium brown color, and long and smooth in shape. They should not require straining to pass or cause pain. Black specks are more noticeable when the stool is light in color than when it is darker.

Visually, the black specks may look like:

  • small, thin flecks
  • coffee grounds
  • dark patches in the stool

Some common causes of black specks in the stool include:


Some foods, such as the skins or seeds of fruit, are more difficult to digest than others. The following foods may leave black specks in the stool:

Food coloring can also cause the stool to change color because the body may have trouble digesting artificial dyes. For instance, black licorice can turn the stool black or very dark brown.

This cause is not necessarily a problem, although, it could mean a person is eating an unbalanced diet when it persists.

Iron supplements

Iron supplements can cause the stool to turn black.

A sudden change could indicate that a person is getting too much iron. Black stools in a child could mean that they have consumed too many iron pills.


Some medications can temporarily change the color of the stool.

Bismuth, an active ingredient in some intestinal medications such as Pepto Bismol, mixes with the tiny amount of sulfur in a person’s saliva and stomach to temporarily add black color to the stool and sometimes the tongue.

The temporary color change is harmless, and it should disappear within a few days of stopping the medication.

A person should consult a doctor about potential stool changes if they have recently started taking a new prescription or over-the-counter drug.

Intestinal bleeding

Bleeding in the gastrointestinal tract, such as in the stomach or intestines, can make the stool appear black. The higher up in the digestive system the bleeding occurs, the darker the blood tends to be.

A person should see a doctor if they experience the following symptoms:

Liver problems

Stool color is a frequent indicator of liver disease. This is because the liver disease can cause cholestasis, where bile is reduced or blocked, sometimes leading to pale-colored stool.

Liver disease can also cause black, tarry stool or black specks in the stool. This is because it can cause bleeding in the digestive tract, a complication called esophageal varices or portal hypertension.

Esophageal varices are bulging veins in the throat and stomach. They happen when blood flow to the liver is blocked. Scar tissue on the liver, often due to cirrhosis, is a common cause of esophageal varices.

Esophageal varices signal a serious liver problem and need to be treated as a medical emergency.

Signs of liver disease include:

Some other conditions, including a blood clot and severe parasitic infections, may also block blood flow to the liver and cause esophageal varices.

A person with liver disease should talk with their doctor about what to do about signs of bleeding.

In newborns, meconium is usually the cause of black, tarry stools. Their stool is dark because they do not yet have the usual friendly gut bacteria that help people to digest their food and have bowel movements.

Once the baby leaves the womb, their intestines become colonized with bacteria, usually in the 24–48 hours following birth, and the stools become gradually lighter.

Older babies can develop black specks in their stools for the same reasons as adults. However, because babies are more vulnerable than adults to infections and diseases, it is important to notify a pediatrician immediately of changes in their stools.

A baby should be taken to the emergency room if they also show signs of:

Learn more about the color of babies’ stools and when to see a doctor.

People who feel otherwise healthy and who have no chronic illnesses can wait a day or so to see if black spots in their stool disappear.

A person should seek medical attention for black spots in the stool if they have:

A doctor should immediately see newborns if the black color is not due to meconium.

People who have had black specks in their stool for more than a day or so should see a doctor if they are not taking medication that turns the stool black.

Similarly, they should see a doctor if they cannot explain the color by any foods they have recently eaten.

Treatment for black specks in the stool depends on the cause. A doctor will take a thorough medical history and may ask for a stool sample.

It may also be necessary to do imaging tests of the colon, stomach, or other parts of the gastrointestinal tract. Liver tests, including blood work, can assess the efficiency of the liver’s functioning.

A person with liver disease may need to take medication, make dietary changes, or spend time in the hospital. If there is internal bleeding, a doctor will want to explore the cause and then have it treated.

Digestion is a complex process, and many factors can affect stool appearance. Many causes of stool changing color or having black specks are not emergencies.

A person should talk with a doctor to find out about personal risk factors related to this symptom, and they should seek prompt care for any troubling changes in stomach or digestive function.

Black specks in the stool are likely due to a person’s diet. The skin of foods such as blueberries and plums can leave the body undigested, appearing as black specks in the stool.

However, if a person’s stool appears black, they should contact a doctor. Although stool can change color due to iron supplements or over-the-counter medications, black stool can indicate more severe health conditions.