Doctors treat all kinds of illnesses, but conditions can still catch them by surprise. That’s what happened when a patient at Wright-Patterson Air Force Base in Ohio opened his mouth to reveal a tongue covered in what looked like green hair. “I had to take a moment to collect myself,” says Dr. Eric Karr. The patient was suffering from lingua villosa—Latin for “hairy tongue.”
Our tongues are covered with small bumps called papillae. They contain taste buds that help detect the different flavors in food. Over time, papillae naturally slough off, and new ones grow in their place. The same thing happens to skin all over your body to replace old or damaged cells with healthy ones.
But sometimes, papillae on the tongue don’t fall off. Instead, they keep growing, reaching up to 18 millimeters (0.7 inches) long. These “hairs” collect food particles, germs, and anything else that happens to be in the mouth. Over time, the tongue’s surface starts to appear black, yellow, or—in this patient’s case—green.
Poor oral hygiene, recent use of antibiotics (medicines used to kill disease-causing bacteria), and a history of smoking can all contribute to cases of lingua villosa. This patient had all three, explains Karr. He advised him to brush his tongue four times a day to remove the overgrown papillae. After a few months, his tongue was back to normal. “It’s certainly a lesson in not smoking and having good oral hygiene!” says Karr.