Smooth Tongue

Having a smooth tongue does not necessarily mean you are a smooth talker. Rather, if it is smooth and pale, it can be a sign of any one of several nutritional deficiencies, such as a lack of folic acid, vitamin B12, or iron. As a result, the tongue loses its rough covering and may become tender and even shrink.

A smooth red tongue, however, can be a red flag for pernicious anemia, a fairly common and easily treatable vitamin B12 deficiency, or malabsorption syndrome, an intestinal disorder in which the body cannot adequately absorb nutrients.

If only a patch of your tongue is red or white and smooth, it may be a sign of Median Rhomboid Glossitis (MRG). This bare spot looks much like a diamond or rhomboid, hence its name. It can be flat or raised and is devoid of both tongue hairs and taste buds. Usually found in the middle of the tongue toward the back, it can be quite small or can grow so large that it covers almost half of the tongue. An uncommon condition, MRG, also medically known as Central Papillary Atrophy, is seen more frequently in men than in women.

People with MRG will sometimes get a Kissing Lesion, a red, irritated spot caused when the bare spot of the tongue rubs up against the soft palate. These  spots may be mistaken for cancer, but they are not. They are, however, susceptible to thrush.

Believe it or not, the longest tongue on record is a mere 3.74 inches (9.5cm). This dubious distinction belongs to a British subject, according to the Guinness Book of World Records.