It's not for nothing that doctors and wellness practitioners in many medical systems around the world all ask their patients to open up and say "ahhh." A close look at your tongue (and everything else you can see inside your mouth) can reveal much about the overall state of your health.

Surface changes: Run your fingertip across the surface of your tongue, and you should feel lots of tiny nodules that feel slightly hairy or fuzzy. These nodules are called papillae, and they're actually small hairs between which your taste buds are scattered. Changes to these hairs may have no rhyme or reason and be totally harmless, or they may be a symptom of an underlying condition.

  • Smooth: Your tongue may feel smooth due to a nutritional deficiency. A pale, smooth tongue could be a sign of iron-deficiency anemia or a lack of B vitamins, which are important to the body's use of food for energy.
  • Map-like patches: If you spot patchy lesions on the tongue that seem to change location from day to day, you may have a harmless but sometimes uncomfortable condition called geographic tongue. It is thought that B vitamin deficiency may be to blame for this tongue surface change, but it could also be due to irritation by alcohol or certain foods.
  • Wrinkled: A tongue that bears grooves, wrinkles, or furrows could be scrotal tongue, a harmless, usually inborn condition that can rarely cause burning sensations when spicy foods are eaten and make it difficult to keep the tongue properly clean and clear of bacteria.

Sores or bumps: We've all bitten our tongue at one time or another, perhaps hard enough to leave a sore spot. In some instances, a spot on the tongue can be a result of something more than surface trauma.

  • A bump on top of the tongue could be a warning of bacterial or viral infection or of an allergic reaction to a food or medication.
  • Canker sores more often pop up on the underside of the tongue, and can be identified by a round, red border and yellow or white centre.
  • A white or gray lesion with a hard surface that feels thick and raised from the tongue could be leukoplakia, a disorder of the mucous membranes caused by irritation from dentures, crowns, fillings, or tobacco use. Hairy leukoplakia, which occurs in people with weakened immune systems due to illnesses like HIV or the Epstein-Barr virus, appears as a fuzzy, white lesion that usually crops up on the side of the tongue.
  • A sore or lump on one side of the tongue may be a sign of cancer and should be looked at by a doctor. Untreated syphilis can develop into a cancer on the top of the tongue.

Colour changes: You've probably noticed how your tongue can change colour depending on what you eat (remember all of the rainbow colours you could achieve as a kid sucking on popsicles?). Variance from the usual healthy pink may be a sign that you're overdoing it with certain habits – or it could signal an underlying condition.

  • Black: From time to time, a person's tongue may take on a black, hairy appearance. "Black hairy tongue" is a harmless, temporary, but unsightly overgrowth of tongue "hair" (papillae) that traps bacteria and other mouth debris. Poor oral hygiene could be the culprit, as could mouth-breathing, excessive use of tobacco, mouthwashes, some antibiotics, or bismuth-based stomach medications (e.g., Pepto-Bismol). Along with the colour change, you might notice a metallic taste in your mouth and generally bad breath. Brush, floss, and try using a tongue scraper to remove bacteria. Black hairy tongue resolves on its own, but check with a doctor if symptoms last beyond 10 days or so.
  • Yellow: As in the case of black hairy tongue, an overgrowth of papillae on the tongue can trap bacteria and appear yellow. These small hairs that coat the tongue can become inflamed by, among other things, smoking, fever, mouth-breathing, and dehydration. Improve your oral hygiene, and the yellow hue should subside.
  • White: White tongue often means the same thing as black or yellow tongue - bacteria stuck in dense tongue hair. And it shares some of the same causes, too: smoking, dehydration, dry mouth due to mouth-breathing. The white look means there are bacteria, dead cells, and debris wedged in the papillae. Pay special attention to your brushing and flossing habits, and add a tongue scraper to your oral hygiene routine. Less commonly, a pale, smooth tongue indicates anemia, and a white film on the tongue could be a sign of oral thrush, a type yeast infection.
  • Red: A red tongue more often signals underlying problems in children's health. A strawberry or raspberry-coloured tongue can be one of the first symptoms of scarlet fever or Kawasaki disease. Adults less often manifest these signs. But if your mouth hurts and your tongue looks smooth and red, your diet may be deficient in niacin, an important B vitamin.
  • Brown: A spot on the tongue that has turned brown or otherwise darkly discoloured could possibly be a form of skin cancer called melanoma.

Any time that you notice pain, burning, swelling, changes in your ability to taste, abnormal movements, or difficulty moving the tongue, do not hesitate to see a doctor.

Amy Toffelmire