Beeturia is the medical name for the presence of red beetroot pigments in urine or feces. After eating beets, around 10 to 14 percent of the general population receives this vivid surprise. Beeturia is generally regarded to be innocuous, however it can be a symptom of iron deficiency in certain people. It can also be caused by some medications such as penicillin and sulfa drugs which induce pigment formation in urine. In medicine, beeturia is used to describe the presence of red blood cells per field under light microscopy of urine or stool samples stained with hematoxylin and eosin (H&E). The term refers to the fact that the urine or stool contains red blood cells when examined under a microscope. A normal human adult produces about 100 million RBCs per day. Thus, one might expect to find between 100,000 and 200,000 RBCs per microliter of urine or colon content if the source was healthy. Higher numbers may indicate an illness or defect in the production of RBCs. People at risk for Bechterev's syndrome should avoid eating foods that contain anthocyanins, particularly berries because they are similar compounds that can cause problems for people with abnormal metabolism. The symptoms usually go away on their own after the person stops eating the beets, but an infection could also cause them to appear in urine.