By observing the root of the tongue coating, we may know the strength of the anti-pathogenic qi and evil qi, deficiency and excess, and the presence or absence of Stomach qi. deficiency or cold syndromes, declining Stomach qi This coating is insubstantial. It seems to be painted on to the tongue's surface. It is easily scraped off the tongue and doesn't seem to even grow from the tongue. Unrooted excess or heat syndrome, no damage to Stomach qi This coating is stable, substantial, and closely sticks to the tongue's surface and is not easily scraped off. Root Rooted indications indications By observing the loss of tongue coating, we may determine the state of the Stomach's yin and qi impending exhaustion of the Stomach yin or qi, poor prognosis The coating is absent over the entire tongue. This gives rise to a very shiny appearance on the tongue.Mirror injury to the yin or qi of the Stomach This coating is missing in some areas and abundant in others. The border between the areas will be obvious, not a gradient. Peeled Geographic IndicationsCoats indications indications