They say that you can tell a lot about your health by looking at the color of your pee: Clear to pale yellow means you're hydrated, and amber to brown means you should probably drink some water ASAP. There are a few outside factors that can influence the color of your otherwise healthy urine. Eating beets, for example, can turn your pee reddish, and asparagus makes your pee smell a little off. Certain medications can also screw with your pee and make it darker. But if you notice that you have actual red blood in your urine, that might be a sign of a more serious medical condition that you shouldn't ignore.
"You should generally be concerned if you see blood in your urine," says Doreen Chung, MD, a specialist in female urology at NewYork-Presbyterian/Columbia University Medical Center. The medical term for "blood in your pee" is "hematuria," Dr. Chung says. It's important to see your doctor if you notice blood in your pee, so that they can test your urine and actually diagnose what's causing it, Dr. Chung says.
Hematuria happens when blood cells enter your kidney or urinary tract, according to the Mayo Clinic. This can happen for a few reasons, most commonly because you have a urinary tract infection, Dr. Chung says. Kidney stones, some kidney diseases, and bladder tumors can also cause blood to appear in urine, she says. A viral or bacterial infection, like strep throat, can cause visible bleeding, too, if the kidney is inflamed as a result, according to the Mayo Clinic.
If you notice blood in your pee after strenuous exercise, as in a marathon or something of similar vigor, then that's usually not a big deal, Dr. Chung says. "It is relatively common and happens in 5 to 25% of people, lasting a few hours to three days," she says. Exercise-induced hematuria is harmless, but you should still talk to your doctor so that they can rule out any more serious causes, she says.
In general, look out for blood spots in your urine, or toilet water that turns pink or red, according to Medline Plus. Sometimes, people confuse period blood or bowel movements with hematuria, so make sure it's actually coming from your urine. You know it's serious if you experience other symptoms, like severe back or flank pain (the area below your ribs), a fever, or if you can't pee, Dr. Chung says. In that case, you should get to the ER right away, she says.
Depending on the cause, your doctor might give you antibiotics to treat the infection and stop bleeding, or they might not prescribe anything at all, according to Mayo Clinic. While you might be used to seeing monthly blood in your underwear, blood in your pee can be a literal red flag that something's up.