Black Stool – What causes Black Stool?
Your stool is an unnerving sign of your overall health condition. Black stool may indicate the condition of your digestive system. You might experience black stool once in a while or on a chronic basis. A single occurrence is basically the indicator of something you had eaten. But if the occurrence is chronic, then it might point towards any serious underlying problem in the digestive tract.
The black colored feces is tarry in nature. It has a strong, typical, foul odor resembling that of wastes. In most cases, consuming certain kind of foods, minerals, medicines or supplements are the cause of black and tarry stools. Such cases are called benign cases. The dietary connection leading to black and tarry stool is called “false Melena”. Medically, the blood coming from some internal bleeding which leads to the discoloration of the stool is called Melena.
- Ingesting certain foods like black licorice or blueberries are the prime causes of false melena.
- Eating more dyed foods will cause more discoloration of the stools.
- Iron supplements can also cause black bowel movements. This indicates that the iron which is consumed could not be absorbed or utilized by the body.
- Certain kinds of bismuth-based medication or medicines with minute amounts of lead can also cause tarry and black colored bowel movements.
- If occurrence of false melena does not reduce over time, or is caused without the intake of any of the foods mentioned above, then medical advice must be taken immediately.
- Black stool must never be ignored. It can be a sign of serious internal bleeding or a cancer.
- The blood mixes with other digestive juices and results in the blackened wastes. The blood also changes its color over time, while getting retained within the body for some time before excretion. This makes the color of the blood darker (blackish) and not red or reddish.
- Such conditions are clinically referred as “true melena”.
- The blood causing black stool is believed to have stemmed from the upper portion of the digestive tract and not from the lower.
- Another condition which can blacken the stool is called gastrointestinal hemorrhage. In these cases, the iron present in the hemoglobin of the red blood corpuscles gets oxidized when the blood passes through the ileum and colon.
Causes of Black Stool
The prime cause of black stool has been identified as the intake of dyed foods and drinks or internal bleeding in the upper gastrointestinal tract. Let us find what causes the bleeding.
Melena, as discussed above, is a sign of a bleeding peptic ulcer, esophageal varices, Malory-Weiss tear or gastritis.
Peptic ulcer –
- Sometimes, bacterial infection can cause soreness of the lining of the stomach. This can gradually aggravate and lead to bleeding.
- Overuse of a few non-steroidal anti-inflammatory (NSAIDs) drugs can also cause peptic ulcers.
- The inflammation of the lining of the stomach is called gastritis.
- There can be many reasons to such inflammations, like wrong eating and drinking habits, overuse of certain drugs, parasital or bacterial infections etc.
Esophageal varices –
- The dilated veins located at the lower wall of the esophagus is called the esophageal varices.
- Any rupture or tear in these veins can also cause bleeding in the esophagus.
Mallory-Weiss tear –
- This is a rare condition.
- Violent coughing, unusual spasms or convulsions, intense vomiting can rarely tear the mucus membrane forming the connectivity between the esophagus-to-stomach. Such a condition is called Mallory-Weiss tear.
Black stool in the newborn –
- Sometimes, the newborn swallows a bit of blood from the mother during its present within the womb.
- This may lead to blackened stool for a few days after birth.
- But this condition is a temporary condition which will clear up in a few days.