There are many reasons for a white tongue, the most common being certain chronic diseases, excessive dampness in the body, dietary reasons, oral cavity itself, and some chronic inflammatory conditions can cause a white tongue. Clinically, patients with early onset or recovery from certain diseases may have a white tongue, such as upper respiratory tract infection, bronchitis and early pneumonia. Most patients with these diseases do not have systemic symptoms and manifestations in the early stage, and most of them have white tongue, which is a normal phenomenon. If the diet is reduced or too much liquid food is consumed, the amount of chewing and saliva will be reduced and the tongue will be attached to the surface of the tongue, which will also cause the tongue to turn white; some oral diseases will also cause the tongue to turn white, such as oral plaque disease and oral candidiasis, the appearance of these diseases will also cause the tongue to turn white. There are many reasons that induce white tongue, so we must distinguish the causes and treat the symptoms, and if necessary, please go to the relevant hospital for consultation and treatment to avoid delaying the disease.