Gosh, you would have to ask why poop is brown, what a question.
Researchers have been pondering the question "why is poop brown" for centuries and still have not quite figured out why.
As it turns out, not all poop is brown. Sometimes poop can be green, yellow or nearly black. On occasion there are pieces of red pepper, tomato skins, corn, peas, etc in it too. But, by far, most poop is a shade of brown.
origin of brown poop has been traced to the writings of Phlatus Odiferous of the ancient Greek city of Athens. In "The Steatopygia", the voluminous writings regarding the derriere, Odiferous recounts that it is desirable for people to have brown poop as other colored poop typically causes anal retentive disease.
The greeks, credited for a great many of mankind's advances, embarked on a worldwide crusade to rid the world of non-brown poop. Historical records from the period expose the
most gruesome acts of mass homicide ever known to mankind. The resulting population had 100% brown poop, all those who had other colors were cremated. A dismal chapter in human history.
There are those who discount the writings of "The Steatopygia" and claim that brown poop was created by God as a result of the great flood of Noah. God reportedly had created a rainbow, and given people brown poop, as a means to remind people that he would never bring another great flood on
As for the chemical process that causes food to turn brown inside the digestive system, the process is rather simple. When water mixes with air inside our digestive system, the walls of the intestine start to rust. It is the mixture of intestinal rust with the digested food that gives the poop the pleasant brown color and distinctive odor. I am told that it tastes alot like chicken too!
So now you know.