Why is poop brown? What does it mean if the poop is green, black or red in color?

The feces are end-products of complex and effective waste management system. The case regarding humans is no different. The feces, or poops as everyone calls it, differ in color and character according to the organisms.
Click image to view in full size
The feces of most vegetarian mammals are of green color, owing to the presence of indigestible chlorophyll in the plants. In the case of birds, the excrement is whitish, because of the white uric salts.
Although the human feces vary among people according to the diet and health, the normal color is brown, with a semisolid character. The 75% of the substance is formed by water. The remaining solid part is composed of many things, including dead and live bacteria, mineral compounds, organic chemicals like fat and proteins and compounds from the digestive juices. All these substances have their role in determining the color of the feces.
The brown color of the poop is largely caused by a substance called bilirubin. To be more precise, the chemical stercobilin, which is derived from the bilirubin is the reason for the brown color of poop. It was first isolated from feces in 1932.
The bilirubin is a product of heme catabolism; that is the breakdown of the hemoglobin, the pigment that gives blood its red color. The hemoglobin is the substance that holds a major role in transporting oxygen and carbon dioxide in the blood system.
The hemoglobin is released with the death of the aged or damaged erythrocytes (red blood cells). It splits then to heme and globin of which the former is further converted into bilirubin. After complex mechanisms and bacterial activities, the bilirubin then is converted to stercobilin and urobilin at the small intestine. These pigments, mostly stercobilin, are responsible for the brown color of poop. The brown comes from the iron present in these substances. Without these pigments, the poop will have the same color of vomit.
The higher consumption of meat can result in the dark brown color of poop, since meat is rich in metals including iron and it leads to more production of bilirubin.
The brown color of the feces is the sign of healthy conditions. The health of a person can be gauged by the color of his/her poop. Poop can appear in various colors, for different reasons. If the color is green, it may be because of the consumption of lot of leafy vegetables. If the color is black, it means the presence of dried blood due to internal bleeding somewhere. It is a dangerous sign. The bright red color also indicates bleeding, mostly an ulcer. You have to consult a doctor immediately in the last two cases.

You might also like:

Leave a Reply

Your email address will not be published. Required fields are marked *