Miley Cyrus can't stop (and she won't stop) sticking out her tongue.
But what is she potentially revealing about her health? It turns out the tongue reveals everything from dehydration to vitamin deficiencies to cancer.
"When we see anything other than that nice pinkish-red tongue with a little saliva -- rather than being coated -- a little alarm bell goes off in our heads that says we should be looking at different things," said Dr. Mark Wolff, a professor at the NYU College of Dentistry.
Last month, Cher criticized Cyrus's VMA performance in a USA Today article, adding, "And, chick, don't stick out your tongue if it's coated."
When a patient's tongue is covered in a grayish-white coating, it's a sign that patient has taken antibiotics that have killed some of the natural bacteria in the mouth, allowing fungus to settle in, Wolff said. It's relatively common, and he sees patients with it a few times a month.
Although this isn't an indicator of overall health, Wolff said the reason Cyrus can stick her tongue out so far is because she doesn't have a large muscle on the underside of it that attaches it to the bottom of her mouth.
"Children and adults who have a little muscle that attaches to the very front of the tongue couldn't spit their tongue out like that if they tried," he said.
Wolff said dentists typically pick up the tongue (usually with gauze) and look at it from all sides during routine exams. Any ulcers or changes in color could hint at cancer, but the tongue can also show other less serious health problems.
Varying degrees of smoothness, redness and swelling can signal different vitamin deficiencies, according to the Merck Manual, a medical textbook.
When the tongue is dry, blistered and red, it means the patient isn't making enough saliva, Wolff said. This can be caused by antihistamines or hypertension drugs.
But if Cyrus gets any of these problems, it's safe to say we'll know it as soon as she sticks her tongue out for the camera.