For those feeling under the weather, the old adage of 'stick your tongue out', may betray the signs of the illness by which they are afflicted.
The tongue can signal signs of a cough, fever, jaundice, headache or bowel habits, and helps doctors make their diagnosis. A healthy tongue should be pink, clean and covered in papillae, which contain taste buds.
But inflamed, red, black or white tongues could be a sign of other conditions such as thrush, while a swollen tongue can be a sign of an allergic reaction. Meanwhile a black, discoloured tongue is indicative of extended antibiotic use, or a fungal overgrowth in HIV patients, say Indian scientists.
And long furrows on the surface are a sign of the sexually transmitted infection, syphilis. Ulcers should ring alarm bells, warning of Crohn's disease or ulcerative colitis. And a 'beefy and smooth' tongue might reveal vitamin B12, iron or folate deficiency, and anemia.
Moving on to more serious conditions, sores or lumps on the tongue - or unexplained bleeding - can be a sign of mouth cancer, warns Cancer Research UK.
Source - Daily Mail