Eat purple potato stools become red, do not be nervous, stool color will be changed by the color of food, so, after eating purple potatoes digestion and absorption, stools become red is a normal phenomenon. No obvious fresh blood attached to the stool, no obvious tar-like black stool, not accompanied by abdominal pain, diarrhea, abdominal distension performance, can be observed for a few days, if the stool color back to normal, no special treatment; if the stool color is still not normal, it is recommended to go to the hospital, so that the specialist can identify, through the stool routine plus occult blood test and other tests to clarify the diagnosis. Most of the cases are caused by food staining. It is recommended to match nutrition, combine work and rest, exercise properly, enhance physical fitness, maintain a good state of mind, develop the habit of regular bowel movements, and observe regularly.