White moss on the tongue may be normal, or it may be caused by coldness of the spleen and stomach (spleen and stomach weakness and cold). There are more causes of white moss on the tongue, so it is recommended to consult a doctor. Tongue moss is a layer of moss on the surface of the tongue. All normal tongues have thin white moss on the surface, which is produced by the stomach qi. Therefore, thin white moss on the tongue is generally normal. White moss on the tongue caused by coldness in the spleen and stomach is often accompanied by abdominal pain and distension, stomach cold and pain, cold and fear of cold, lack of warmth in the limbs, a preference for warmth and pressure, loss of appetite, a light mouth with no thirst, and a sluggish and feeble pulse. Note that if white moss on the tongue is accompanied by other discomforts, it is recommended to consult a doctor in time to identify the cause and carry out targeted treatment.