The cause of thick and greasy tongue may be phlegm-dampness, water-dampness, cold-dampness, or accumulation of food in the body (the food is indigested and stops accumulating in the stomach), etc. The patient will have phlegm-dampness during tongue diagnosis. 1. Phlegm-dampness: Generally, it is caused by eating fatty, raw and cold food, which causes the spleen and stomach to malfunction, resulting in phlegm-dampness, and the patient will have a thick and greasy tongue at the root of the tongue during the tongue diagnosis. 2. Water-dampness: mainly because of the humid environment, the body becomes heavy with dampness, which will lead to the swelling of the tongue, the two sides are easy to appear teeth marks, and the root of the tongue will be thick and greasy, and the tongue moss is usually white. 3. Cold and dampness: mainly due to the invasion of cold, in addition to the symptoms of white tongue coating, thick and greasy tongue root, there are usually cold, fear of cold and other symptoms. 4. Food stagnation: If there is food stagnation in the body, there will also be a thick and greasy tongue, there will also be abdominal distension, abdominal pain, sour and rotten gas in the mouth and other phenomena. It is recommended that timely medical standardized diagnosis and treatment, usually more exercise, diet as light as possible, avoid cold.