Tongue coating is normal if it is a thin layer of white moss; if it is a thick layer of white moss, it is called greasy moss, which is related to dampness, phlegm and drink (pathological products of impaired metabolism of water and fluid), or food stagnation (accumulation of indigested food in the stomach). Chinese medicine tongue diagnosis that the normal human tongue is thin white moss, that is, a thin layer of white moss flat on the tongue, which is the performance of the stomach qi enough. When the white moss becomes thicker, it is greasy moss, which is abnormal, i.e., a thick layer of white moss spreads on the tongue surface, suggesting that there may be dampness, phlegm or food accumulation. If phlegm-dampness is present in the tongue, it may be accompanied by drowsiness, loose stools, heaviness, dullness (lack of appetite, reduced food intake), etc. Er Chen Tang and Wen Gallbladder Tang can be used to treat this condition. If food accumulation is present, it may be accompanied by overeating and excessive eating, so hawthorn, malt bud, and shen qu can be used to treat this condition. The above prescriptions should be used under the guidance of a Chinese medicine practitioner and should not be taken at random.