Answer: It may be due to bile pigment in the stool because diarrhea moves food too quickly thorough the intestine so the intestinal chemicals and bacteria can't break down the bile pigment to its normal brown color, or the green color may be due to certain foods like green, leafy vegetables or green food coloring.
Explanation: Although green stools aren't usually a cause for concern or a sign of cancer, you shouldn't ignore green poop that's accompanied by other symptoms. If you experience green stools without any other symptoms, the culprit is probably leafy green vegetables or food coloring.