Suffering from the movements of the dark bowel? The black-colored stool is a phenomenon which is the result of the bleeding in the intestines. The blood in the mix paints the stool in dark brown or even black. In fact, many factors could cause dark bowel movements, but the majority of them are rather bad symptoms. We recommend consulting your physician immediately to avoid adverse consequences. In the case of the acid flux, this sign is just the result of serious cramping and straining.