What is tongue coating? What causes dark red tongue coating?

As our quality of life improves, our food consumption has also greatly increased, which has led to the emergence of many health problems. Experts suggest that a person’s physical condition can be seen from his tongue. So do you know what dark red tongue coating means?

What is tongue coating?

Tongue coating, a term in traditional Chinese medicine. A normal person has a thin, white, and moist coating on the back of his tongue, which is called tongue coating. It is composed of desquamated keratinized epithelium, saliva, bacteria, food debris and exuded white blood cells. Under normal circumstances, the chewing and swallowing movements, as well as the flushing of saliva and food, constantly remove substances from the surface of the tongue, leaving only a thin white layer of tongue coating. When one is sick, one eats less or only eats soft food, which reduces chewing and tongue movements, or reduces saliva secretion, and the tongue coating becomes thicker. The tongue coating of a normal person is generally thin and evenly spread on the surface of the tongue, and is slightly thicker in the middle and root of the tongue.

Because the tongue coating is produced by the stomach qi, and all the internal organs receive qi from the stomach, changes in the tongue coating can reflect the coldness, heat, deficiency or excess of the internal organs, the nature of the pathogenic factors and the depth of the disease. Observation of the tongue coating includes two parts: observing its color and its texture.

Coating color: the color of the tongue coating. Pathological coating colors mainly include white coating, yellow coating, and gray-black coating. Sometimes green tongue coating (mostly transformed from white tongue coating, common in febrile epidemics and damp-heat, a sign of damp-heat stagnation) and moldy tongue coating (red with black and yellow spots on the tongue, common in heatstroke or long-term internal heat, and a sign of long-term damp-heat disease) may also occur.

Tongue coating manifestation

1. White tongue coating: generally indicates external symptoms and cold syndrome. A thin, white and moist tongue coating is a normal feature of a person's tongue. At the same time, a thin, white coating also indicates that the disease is on the surface of the body and has not penetrated into the interior. The tongue coating is thin, white and overly smooth, which is often seen in symptoms of superficial cold. The tongue coating is thin, white and dry, which indicates superficial heat or infection with dryness. The tongue coating is thick, white and dry, indicating that dampness turns into yellow coating and heat damages body fluid. The tongue is covered with white fur and is not dry to the touch, which is called "powdery white fur" and indicates plague. The tongue coating is white and dry, which is called "rough and cracked tongue coating" and is often seen in febrile diseases. A pale tongue with a white and smooth coating indicates cold syndrome or cold-damp syndrome. The tongue coating is white, smooth and sticky, which is seen in the body with phlegm and dampness or dampness trapped in the spleen. The tongue coating is white, slippery and rotten, which indicates heat accumulation in the stomach. If the tongue coating is white like snowflakes and dry, it is called "snowflake tongue coating", which indicates a cold spleen. If the tongue and mouth are covered with raw cloth, moldy coating, or erosion spots, it is a dangerous sign of stomach qi deficiency and impending extinction of internal organs.

2. Yellow tongue coating: Yellow tongue coating indicates internal heat syndrome. If the tongue coating is thin, yellow and dry, it means that the internal heat is excessive and the body fluids are damaged. The tongue coating is yellow, dry and prickly, and there are cracks on the tongue, which indicates that the internal heat is extremely severe, the body fluids are severely damaged, and the internal organs are extremely hot. The tongue coating is thick and greasy, which is usually caused by phlegm heat, food accumulation or internal damp heat. The tongue coating is yellow, smooth and moist, which is a sign of yang deficiency.

3. Gray tongue coating: mainly indicates internal symptoms. The tongue coating is thin and smooth, which is mostly caused by internal obstruction of cold and dampness, or stagnation of phlegm and fluid. Gray and dry tongue coating indicates fever or yin deficiency and excessive fire.

4. Black tongue coating: Black tongue coating is mostly transformed from yellow tongue coating or gray tongue coating, indicating that the condition is extremely serious. Black and dry tongue coating indicates excessive heat and deficiency of body fluid. The tongue tip has black and dry coating, which indicates excessive heart fire. The tongue coating is black and smooth, indicating extreme yang deficiency and yin cold.