It is common practice in traditional Chinese medicine to examine the size, shape and movement of the tongue and use it to diagnose a range of illnesses.
For instance, a bright red tongue indicates a Yin, or excess heat. The darker the red, says scientists in an article in The Journal of Traditional and Complimentary Medicine, the warmer the body is.
While Western medicine does not follow these exact guidelines, experts agree the tongue is a useful tool and can be used in the diagnoses of many diseases.
Just stick out your tongue the next time you are feeling under the weather – it might just point to the cause of your illness.
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The normal tongue
First it’s a good idea to look at what a normal tongue looks like. It’s supposed to be a pink-ish colour and is usually an indication of good oral health.
When your tongue is a bit swollen and has smooth white areas, the chances are good you have glossitis – or more commonly known as inflammation. Research from The New York Times indicates “glossitis is often a symptom of other conditions or problems”, which include an allergic reaction to toothpaste or mouthwash, low iron levels, a yeast infection or so-called “dry mouth syndrome”. Antibiotics and antifungal medications are often prescribed after the doctor has identified a possible root cause.
This colour might indicate the presence of median rhomboid glossitis (MRG), also known as central papillary atrophy, which presents as “a smooth, red, flat or raised nodular area on the top part (dorsum) of the middle or back of the tongue”, according to the American Academy or Oral Medicine. The condition is not contagious or dangerous, but can be accompanied by a burning sensation in the mouth.
It sounds very gloomy to have a “black hairy tongue”, but according to The Mayo Clinic this is a harmless oral condition and goes away without any treatment. This condition results from the build-up of dead skin cells on the surface of the tongue, which is then stained by tobacco, food or other substances. These cells are usually longer, giving a “hairy” feeling to the tongue. Practicing good oral hygiene, cutting out triggers such as tobacco, and certain foods, might help to avoid this condition.
A yellow colour can be an early indicator of “black hairy tongue”, but depending on the amount and texture of the yellowness, it can be an indication of oral thrush, also known as oral candidiasis. Research from the Centre for Disease Control in the USA says this is a fungal infection that occurs when there is an overgrowth of yeast called Candida. You might experience difficulty swallowing, but antifungal medication will most likely take care of it.
If your tongue or mouth discolours to a dark brown and the texture changes to a “wound-like” feature, it might be an indication of oral cancer and you should get it checked out immediately. The growth of the tumour might not be noticeable at first, says research from the Oral Cancer Foundation, but it’s important to regularly inspect your mouth for any possible lesions.