Chances are, you won’t have heard of geographic tongue,
although you may have experienced this distressing
condition without ever giving it a name. Figures of exactly
how many people are affected by geographic tongue vary.
According to the authoritative review study concluded in
1992 –called “Incidence of tongue diseases based on
epidemiologic studies” by Drs. Dombi and Czeglédy,
geographic tongue affects around 3 percent of adults
worldwide. The incidence in the US is the same.
Source – how to get rid of geographic tongue