What's the matter with people pooping black

In order to better understand our physical condition, we can judge from our own feces. The color, texture, shape, etc. of the feces can reflect the health of our body. Some people's feces are black. There are many factors that lead to this situation. Sometimes it is dietary factors. For example, if we eat something black, then the feces will naturally be black. So what other factors can cause black stool?

What causes black stool?

When bleeding occurs in the upper gastrointestinal tract, including the esophagus, stomach, duodenum, upper jejunum, pancreas, and bile duct, the iron in hemoglobin in red blood cells combines with sulfide to form iron sulfide under the action of intestinal bacteria, making the stool appear black.

However, it is important to note that tarry black stools are only a typical manifestation of upper gastrointestinal bleeding. The stool color changes during upper gastrointestinal bleeding are not always tarry, but vary greatly. For example: when the amount of bleeding is relatively small, the change in stool color cannot be detected by the naked eye and can only be detected through special tests; when the amount of bleeding reaches more than 50 ml, the stool color becomes darker, which can be seen by the naked eye. However, in addition to the tarry stools mentioned above, the color of the stools can also turn into brown, reddish brown or even bright red when there is upper gastrointestinal bleeding.

The changes in stool texture, softness and color during upper gastrointestinal bleeding depend entirely on the site of upper gastrointestinal bleeding, the amount of bleeding, the rate of bleeding and the time the blood stays in the intestine. If the amount of bleeding is large and the bleeding speed is fast, and the stool stays in the intestine for a short time, the texture of the stool will become very soft or even close to liquid, and the color may further change from black to reddish brown or even bright red. Typical tarry black stools may only appear when the amount of upper gastrointestinal bleeding is relatively small, the bleeding rate is relatively slow, and the bleeding stays in the intestine for a long time.

Judging your health from the color of your stool

1. Red

If there is red color on the surface of the stool or blood dripping after defecation, the possibility of hemorrhoids, anal fissure and rectal cancer should be considered. To distinguish rectal cancer from the first two diseases, it is necessary to observe the thickness of the stool. If the stool becomes obviously thinner, the possibility of rectal cancer is greater. If the stool is mushy and mixed with red, you should consider whether you have acute hemorrhagic enteritis.

2. Black

Black and shiny stools are typical of upper gastrointestinal bleeding, with stomach and duodenal bleeding being common. The reason is that the blood undergoes various chemical changes in the intestines, mainly the reaction of iron and sulfide in the blood to form iron sulfide, which makes the stool black. Among patients with upper gastrointestinal bleeding, about half suffer from bleeding due to ulcer disease, most of which are duodenal ulcer bleeding. In addition to ulcer disease, cirrhosis combined with rupture of esophageal or gastric varicose veins and gastric cancer are also common causes of upper gastrointestinal bleeding.

3. Green

Green stool can be caused by many reasons, and they are usually thought to be caused by food being digested too quickly, or by eating large amounts of vegetables or green food dyes. In other cases, an allergy to fennel oil or a side effect from taking iron supplements can cause this phenomenon.