The tongue serves as a portable living health report. By learning tongue diagnosis, one can self-examine and detect serious health issues at the first sign, without needing to seek help for minor ailments.
The tongue corresponds to the five internal organs.
In fact, each of the five organs has a corresponding area on the tongue. The tip of the tongue reflects information about heart and lung diseases, the center of the tongue reflects spleen and stomach issues, the sides of the tongue correspond to liver and gallbladder conditions, and the root of the tongue generally indicates issues in the lower jiao, including the bladder and kidneys. The following image illustrates this clearly.
A normal tongue should have a pleasing color, typically ranging from light red to pale pink. If the tongue is too pale or white, it indicates cold or deficiency of qi and blood; if it is red or dark red, it suggests the presence of heat in the body; if it appears dark purple, it indicates blood stasis.
The thickness and size of a normal tongue should be moderate.
A tongue that is too large indicates spleen deficiency;
if there are teeth marks, it signifies a more severe version of spleen deficiency—spleen dampness;
if the tongue is too thin, it indicates qi stagnation;
if it is both thin and narrow, it suggests deficiency of qi and blood;
if there are spots or petechiae on the tongue, it indicates blood stasis;
if the tongue papillae are significantly enlarged and swollen, it indicates a heat syndrome; if there are cracks in the center of the tongue, it suggests deficiency of qi in the spleen and stomach.
Examining the tongue coating.
Let’s analyze the different colors of tongue coating and their corresponding conditions.
1. White Coating
White coating generally indicates the presence of cold dampness in the body, which is particularly common in modern individuals. Why? Because modern people often experience high work pressure and irregular eating and sleeping habits, leading to dampness in the spleen and stomach, which manifests on the tongue.
White coating can be seen in healthy individuals (sub-health state) as well as in cases of mild illness, early stages of disease, and recovery phases. It may indicate early-stage or localized lesions that have not yet affected the entire body.
2. Yellow Coating
Yellow coating generally represents heat in the body. If the tongue coating is yellow and greasy, it indicates damp-heat in the body, at which point one should clear heat and eliminate dampness, and regulate the spleen and stomach.
In cases of cold and fever, yellow coating may appear within two days, indicating a close relationship between fever and yellow coating. Treatment should focus on cooling herbs and avoiding spicy and stimulating foods to prevent exacerbating the condition.
3. Gray-Black Coating
This is primarily caused by the proliferation of the filiform papillae on the tongue. The color of black coating can vary from brown-black, gray-black, charred black to pitch black. The presence of this coating indicates a longer disease duration and a more complex and severe condition.
Among patients with black coating, half of the cases are caused by various inflammatory infections, and various late-stage cancers can also present with black coating, indicating a critical stage of illness.
However, black coating does not necessarily indicate severe illness; poor oral hygiene and infrequent brushing can promote fungal growth and excessive keratinization of the tongue papillae, leading to black coating. Regular smokers and those who frequently consume traditional Chinese medicine may also develop black coating due to drug residue staining, which will improve after discontinuation of the medication.
Understanding the significance of tongue coating colors allows us to infer the severity of illness. If the coating changes from white to yellow, it indicates that the pathogenic factor has moved from the exterior to the interior, and the condition has worsened from mild to severe, with a change from cold to heat. Conversely, if the coating changes from yellow to white, it is a positive sign.
Abnormal Tongue Shapes
In addition to examining the color of the tongue coating, we can also assess the shape and size of the tongue to determine health status.
1. Teeth-Marked Tongue
A teeth-marked tongue indicates qi deficiency. Individuals with this condition often have weak spleen and stomach, tend to be quiet and lethargic, and may experience cold hands and feet.
For those with a teeth-marked tongue, it is advisable to avoid raw and cold fruits and drinks, as they can damage spleen yang and exacerbate dampness. Moxibustion can be used to regulate the spleen and stomach, or one can drink a decoction of Fu Ling (Poria) and Bai Zhu (White Atractylodes).
2. Cracked Tongue
Prominent cracks in the center of the tongue (while all individuals have some cracks, they are usually not noticeable in healthy individuals) indicate poor spleen and stomach function, with insufficient qi to lift the tongue coating, resulting in noticeable cracks.
3. Deviated Tongue
A deviated tongue often indicates a precursor to a stroke. If the root of the tongue feels numb and the index and middle fingers feel stiff, this may be a sign of a stroke due to cerebral ischemia. In such cases, it is crucial to seek medical attention promptly.
4. Stasis-Dot Tongue
In menopausal women, if there are numerous stasis dots on the sides of the tongue accompanied by irritability, this indicates a disorder of endocrine metabolism and pigment deposition.
Traditional Chinese medicine believes this is due to liver qi stagnation, leading to internal blood stasis. In this case, one can take some liver-soothing and qi-regulating herbs, such as Chai Hu (Bupleurum) or Xiao Yao Wan (Free and Easy Wanderer), for quicker results.
5. Sub-lingual Veins
Two veins flow quietly under the tongue, which are normally faintly visible or not visible at all. However, when there is stagnation in the body and poor circulation of qi and blood, these veins will become prominent, indicating a risk of cardiovascular and cerebrovascular diseases.
6. Tongue Mobility
Individuals with weak righteous qi and deficient yin fluids, as well as those with internal wind, may experience tongue tremors. A normal tongue is very flexible; if someone struggles to extend their tongue, it indicates significant damage to righteous qi or a severe illness.
