The main reason is that red dragon fruit is rich in phytochrome. This plant pigment is absorbed into the body through the gastrointestinal tract after consumption and needs to be excreted by the kidneys, when the pigment will enter the urine, the excreted urine will appear red. General urine reddening phenomenon in the stop eating dragon fruit will soon be restored, in just after eating dragon over may have urine red urine for the first few times, but will soon return to normal. If the red color of urine persists, the presence of hematuria should be considered. It is recommended to go to the hospital for urine routine and urinary ultrasound to see if the level of red blood cells in the urine is elevated and if the urinary ultrasound will reveal organic lesions in the urinary system.