Healthy people who eat greasy food in moderation will generally not have a thick white tongue; if they eat too much greasy food, or if they have phlegm (a pathological product of impaired water metabolism) or food accumulation (food that is indigestible and stagnates in the stomach), they may have a thick white tongue when they eat greasy food. If too much greasy food is eaten, the function of the spleen and stomach may be impaired, resulting in fullness and tightness in the epigastrium (stomach and abdomen), loose stools (thin, unformed feces), loss of appetite, and a thick white tongue coating. People who have phlegm and food accumulation may eat greasy food, which may cause distension of the epigastrium, heaviness of the limbs, sticky and greasy mouth, or abdominal pain, vomiting, diarrhea, loss of appetite, and a thick white tongue coating. Daily diet should be light and avoid excessive or prolonged intake of greasy food. If you have any of the above symptoms, it is recommended that you seek prompt medical treatment.