A thin tongue is normal. The normal tongue is formed by mixing the filiform papillae of the tongue with food debris. It is normally white and relatively thin, and it is only a disease if the tongue is completely missing. This is when the surface of the tongue is very smooth and mirror-like, called mirror tongue. It is mainly due to the atrophy of the filiform papillae on the surface of the tongue and even the mucosa of the tongue, which is reddish in color. If the tongue coating is thin and white, it means that there is no disease in the body that can be seen from the surface of the tongue, and the tongue is normal. Chinese medicine can look at the pulse and the tongue. If the tongue coating is normal and the color of the tongue body is normal, the tongue is normal.