White and greasy tongue coating is usually not related to dampness or heat. White and greasy tongue coating often represents internal accumulation of dampness, food accumulation (accumulation of food in the stomach due to indigestion) or phlegm-drinking (pathological products formed by impaired metabolism of water and fluid), while yellow greasy moss and accumulation of powdery moss often represent dampness-heat syndromes. White moss is the original color of the tongue and is the most common color of the tongue, and all other colors can be transformed from white moss. White and greasy tongue coating mostly represents internal stagnation of dampness and turbidity, food stagnation (accumulation of food in the stomach due to indigestion) or phlegm-drinking (pathological products formed by impaired metabolism of water and fluid). If the tongue coating is as white as accumulated powder and is not dry to the touch, it is called accumulated powder coating, which is related to dampness-heat, mostly formed by the combination of dampness and heat-toxin. Yellow greasy moss often represents dampness-heat syndrome. Yellow greasy moss refers to moss that is yellow in color and delicate in texture, and is mainly associated with dampness-heat accumulation (dampness evils and heat evils gather each other in the body), food accumulation (food that is indigested and stagnates in the stomach) and putrefaction, or phlegm-heat internal accumulation. Yellowish greasy moss on the tip and edge of the tongue and grayish black moss in the tongue are mostly caused by the accumulation of dampness and heat, which does not dissolve over time. If you have an abnormal tongue color or feel unwell, it is recommended that you go to the hospital in time for early diagnosis and treatment under the guidance of a professional physician.