Eating red dragon fruit will appear red and black stools, to be precise, the color of the stool should be purple-red. Because dragon fruit contains anthocyanin, which is not digested and absorbed by the body, the feces discharged will be red and the urine discharged is also red. Black or red stools and red urine last about 1-2 days to recover, and no more than 3 days at most. Moreover, black and red stools do not have a special smell, and the number and nature of the bowel movements are the same as normal stools. If you are not sure, you can go to the hospital and cooperate with the doctor to check the stool routine plus the occult blood test to clearly rule out the presence of gastrointestinal bleeding.