Geographic Tongue is a benign condition of the tongue that makes the surface of the tongue look a bit like a map (geography). The fine hair-like villi that cover the surface of the tongue change, and the tongue looks smoother and redder in some areas. The red areas sometimes look like continents floating on an ocean. The red areas will change shape with time so the look of the map changes from week to week.
The cause of geographic tongue is unknown. It seems to have no significance other than visual uniqueness. Some people have it and some don't. Studies indicate about 1 - 3% of the population have it. It seems to be genetically influenced since it exists more frequently in families. There have been no consequences from it identified.
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