What causes green stools?

Hello. Thank you for writing.

Green stool is usually the result of a high quantity of leafy, green vegetables in someone's diet. Specifically, it is the chlorophyll in the plant that produces the green color. Sometimes, children might have green stool after attending a birthday party where they ate artificially colored frosting.  Diet-based reasons for green stool are the most common, but there are others.   Certain infections, like those caused by the bacterium Salmonella or the parasite Giardia, can also cause green stool. But other symptoms, including severe diarrhea, abdominal cramps, and fever, are common with these illnesses.

Helena