Tongue Diagnosis


Edward Thompson MA, LCH, CH, Dip.BSS, Dip AC, Dip.CHM, RCST

Year of publication: 

We all rely on our bodies to tell us when something is wrong. Besides the skin, hair and nails as indicators of internal imbalance, the tongue can also provide us with vital clues. In fact, in Chinese and Indian medicine, observation of the tongue plays a fundamental role in determining a person’s state of health. Although not backed by scientific research, tongue diagnosis dates back several thousand years, and has long been used as an investigative tool by practitioners of such schools of medicine. As an introduction, Edward Thompson MA, LCH, CH, Dip.BSS, Dip AC, Dip.CHM, RCST provides the basics into this ancient diagnostic art.

Modern Western medicine recognises that the tongue can be a mirror of illnesses which are systemic and not just local to the tongue. But unlike Chinese or Indian medicine it does not develop observation of the tongue into a general system of diagnosis. For example, glossitis (inflammation of the tongue) causes a red sore tongue which can occur as a result of vitamin B deficiency, especially vitamin B12 or as a result of a lack of iron. A swollen tongue can be a sign of hypothyroidism, as well as of acromegaly, a disease of the anterior pituitary gland where too much growth hormone is produced. It is also commonly observed that children suffering from a fever may develop tongue ulcers.

In Chinese and Indian medicine the tongue is seen to reflect the degree of health or imbalance of the body. The tongue is examined to assist in diagnosis and to the extent in which the tongue changes with treatment can indicate how successful the treatment has been. It is important to emphasise that neither Chinese nor Indian medicine rely only on the tongue for diagnosis, seeing it as an important but not exclusive part of the diagnostic process.

To understand the concept of tongue diagnosis in relation to Chinese and Indian medicine, a basic knowledge of the principles of each system is necessary.


TCM is the traditional system of medicine of China and has evolved over a period of more than 2,500 years. At the centre of TCM is the concept of yin and yang, two opposites which are totally interdependent, existing only in relationship to each other. They are responsible ultimately for the appearance and the rhythms of life both in the external environment and in the internal environment of the body.

Also fundamental to Chinese medicine are the organ and energy (qi) systems of the body. The organ systems of the body are collectively referred to as the zang fu. Each of these zang fu are responsible in health for specific functions in the body and if they become imbalanced they produce specific symptoms and signs.

The zang fu are said to be affected by what are called the pathogenic factors - fire, cold, dampness, dryness, wind and summer heat. They can come from either outside of the body, or with the exception of summer heat can be generated from within the body. Each of the pathogenic factors will cause specific symptoms depending on which of the zang fu they affect.


Ayurveda is the traditional system of medicine of India and is at least 5,000 years old. As with Chinese medicine it has its own understanding of body function and the imbalances which cause disease. At the heart of Ayurvedic medicine is what are called the tridosha. These tridosha are to some degree similar to the old European medieval idea of the humours. The tridosha are vata, pitta and kapha. In health they are responsible for the function and structure of body. However, if they become excessive or deficient either individually, or in combination, then they cause illness. Vata, pitta and kapha are made up of the five elements of Ayurvedic medicine which are ether, air, fire, earth and water. Imbalance of the tridosha can cause the following symptoms:


  • constipation with dry stool hyperacidity excess mucus production
  • dryness of the skin inflammatory conditions overweight
  • anxiety and insecurity peptic ulcer greed and attachment
  • tremors liver and gallbladder imbalances slow elimination with heavy pale stool
  • dizziness hives and rashes dull, heavy deep pain
  • sciatica anger and irritability bronchitis, sinusitis and lung congestion
  • paralysis excessive appetite sensations of heaviness
  • neuralgia oily yellow loose stool
  • gas burning and piercing pain
  • variable appetite dizziness
  • pain which changes location and is tearing


The tongue is seen as a map of the body, and in both TCM and Ayurveda, the tip of the tongue represents the upper part of the body and the base of the tongue the lower part of the body. However, they do not entirely agree on where the organs are located on the map! Organs in Chinese medicine do not necessarily have the same function as the organs in Ayurvedic medicine. The area of the tongue that exhibits a change in appearance, corresponds to the organ which the tongue mirrors in that area. For example, in Ayurvedic medicine discolouration towards the centre of the back of the tongue indicates an imbalance in the colon, whilst markings along the mid line of the tongue indicate the spine is affected.


Tongue diagnosis can be simply divided into the examination of the tongue body and the tongue coat. A normal tongue is seen as being a healthy reddish pink with a very thin white coat which may be more pronounced in the morning. Any deviation from this norm is caused by an imbalance within the system. Both the colour and the shape of the tongue are important in diagnosis.


A red tongue in Chinese medicine indicates heat in the body. Heat can be caused either by excess of yang which causes excess heat and creates one set of symptoms or by a deficiency of yin which causes deficient heat and creates another set of symptoms. Excess heat often relates to inflammation and possibly infection in Western medicine. Some tongues have red spots on them and this too is a sign of heat. It is possible for a tongue to be of normal colour but have small red spots.

Where there is excess heat in the body, foods which are considered to be warm in nature should be avoided - these include red meat, excess refined sugar, spicy food, chicken, alcohol and coffee. The diet should be light with increased portions of vegetables, and little or no meat. Food should be raw, steamed or boiled and not fried in oil or butter.

Excess heat - excess yang

Fever, a red face and flushing, thirst, sweating, a feeling of heat, constipation, dark and scanty urine, dryness in the mouth and throat and a strong rapid pulse.

Deficient heat is due to a lack of yin in the body. Yin is cool and moist in quality and so when it becomes deficient it is unable to balance the hot and dry nature of yang which produces the picture below:

Deficient heat - deficient yin

Low grade fever worse in the late afternoon and evening, night sweats, sensation of heat and burning in the palms of the hands, soles of the feet and the centre of the chest, thirst quenched in sips which becomes more pronounced in the late afternoon and evening, a weak and rapid pulse.

The picture of deficient yin usually occurs as a result of over work and a hectic stressful lifestyle. It needs to be treated by foods that are nourishing, build up the body and increase fluids. The following foods might be chosen to assist healing in someone with either excess or deficient heat. They all have a cooling action on the body. However, those which work on yin deficiency are more building and strengthening in effect.

Foods for deficient heat -yin deficiency

  • Asparagus
  • Pears
  • Seaweed
  • Wheat
  • Rice
  • Grapes
  • Banana
  • Tofu
  • Green beans

Foods for excess heat -yang excess

  • Watermelon
  • Lettuce
  • Cucumber
  • Soya milk
  • Barley
  • Seaweed
  • Mung beans
  • Coriander leaf juice

Where there is a red tongue due to yin deficiency there is very little or no coat at all, the tongue may have a shiny mirror-like appearance and may also be cracked. If the cracks are in a particular area of the tongue then the yin deficiency affects that area of the body that the tongue corresponds. In most cases of excess heat the tongue will have a yellow coat. In both cases because there is heat in the body the tongue may appear dry; the drier the tongue the more extreme the heat.

In Ayurveda a red tongue indicates a pitta imbalance whilst a cracked tongue indicates a chronic imbalance of vata affecting the colon.


A pale tongue always indicates deficiency. Which type of deficiency will depend on other factors revealed on the tongue, as well as the presenting symptoms. A pale tongue indicates a deficiency of yang, qi (energy) or blood. If the tongue is pale and moist it indicates a deficiency of yang which is also sometimes called deficient cold as it causes cold symptoms in the body.

Yang deficiency - deficient cold

The person feels easily cold especially in the limbs and tends to wear more clothes, desire for hot drinks, loose stools, exhaustion, lack of motivation, depression, sensitivity to the cold, a slow and weak pulse

A pale tongue always indicates deficiency. Which type of deficiency will depend on other factors revealed on the tongue, as well as the presenting symptoms Yang deficiency needs to be treated with foods which are warm and tonifying in nature. In qi (energy) deficiency the tongue is pale and is often scalloped in appearance although it may be scalloped in yang deficiency too. The scalloped tongue is slightly larger than normal and so presses onto the teeth which then causes the tongue to have indentations. The spleen qi is of special importance in qi deficiency and of particular interest to nutritionists because the function of the spleen is the digestion and absorption of food. It can be seen from this that it is a mistake to assume that the Chinese understanding of the zang fu is similar to that of Western Medicine’s understanding of the organs, as the spleen has no part to play in digestion in Western physiology.

Qi deficiency

Shortness of breath, easy sweating, tiredness, poor appetite, apathy, abdominal bloating, weakness of the muscles, a sallow complexion.

Finally a pale tongue may also indicate blood deficiency, which is not the same as the Western disease of anaemia but has similarities in some of the symptoms which are produced.


Blood Deficiency

Pallor, dizziness, dry skin, palpitations, scanty periods, dry eyes, weak pulse.

The foods which may be used to help to treat blood, qi or yang deficiency are:

Foods for yang deficiency

  • Garlic
  • Cloves
  • Cinnamon bark
  • Dry ginger
  • Walnuts
  • Lamb

Foods for qi deficiency

  • Grapes
  • Dates
  • Sweet potato
  • Malt
  • Rice
  • Chicken
  • Beef

Foods for blood deficiency

  • Red grapes
  • Raspberries
  • Chicken
  • Egg yolk
  • Red meat
  • Liver

In Ayurveda a pale tongue is said to be due to a lack of blood in the system. Blood forms one of the dhatus (body tissues) of Ayurvedic medicine and is called rakta. A scalloped tongue is seen as it is in Chinese medicine to be caused by poor assimilation of foods.


A blue tongue is caused by coldness, whilst a purple tongue is caused by failure of blood to move properly - which the Chinese refer to as blood stagnation. It however can also be caused not by a lack of yang but by too much cold. A purple tongue with a bluish tinge is due to coldness causing blood to stagnate, whilst a reddish purple tongue is due to heat causing the blood to stagnate. Where there is excess cold, the tongue has a thick white coat.

Excess Cold

Pale, often overweight, water retention, normal energy levels, excess mucus, cold hands andfeet, copious and clear urination, abdominal pain better for heat but worse for pressure, loosestools and a strong pulse.

Blood stagnation

Sharp, fixed stabbing pain which is worse for pressure, irregular periods with clotted purple blood, purple lips and complexion.

Foods for blood stagnation

  • Leeks, Chives
  • White pepper, Cayenne, Nutmeg
  • Vinegar
  • Ginger
  • Aubergine
  • Butter
  • Rice
  • Basil, Rosemary
  • Garlic

Foods for excess cold

  • Onions, Leeks, Chives
  • Cinnamon bark, Cloves, Cumin, Caraway, Fennel, Chilli, Pepper, Ginger
  • Oats
  • Walnuts
  • Parsnip
  • Lamb
  • Chicken
  • Beef
  • Anchovy
  • Trout
  • Dates
  • Citrus peel


A yellow coat indicates internal heat in the body, a white coat indicates cold. If the coat is thick then the degree of heat or cold is more pronounced than if the coat is thin. If the coat appears greasy it is due to dampness accumulating in the body.


Fluid retention, swelling, heavy sensation in the head and muscles, lethargy, sticky mucus discharge, a feeling of fullness in the abdomen and loss of appetite.

Dampness may occur either with heat or cold. Foods which reduce damp work by stimulating the digestion to improve absorption and often cause increased urination to “drain” the dampness from the body.

Foods which reduce dampness

  • Parsley leaf
  • Barley
  • Mushrooms
  • Grapefruit and tangerine peel
  • Corn
  • Broad beans
  • Hops

In Ayurveda, a thick tongue coat is caused by ama, which is a toxic sticky residue that builds up in the body and causes obstruction and heaviness. A thick greasy yellow coat indicates what is called ama jvara which is ama accompanied by fever, whilst a simple yellow coat indicates increased pitta. A white coat with mucus on it is caused by an excess of kapha.


Vata balancing foods Pitta balancing foods Kapha balancing foods
Sweet fruits such as bananas, coconuts, cherries, grapes and figs Sweet fruits as for vata, but sour fruits should be avoided Apples, apricots, prunes, raisins
Cooked vegetables such as asparagus, carrots, garlic, green beans, onion and sweet potato Sweet and bitter vegetables such as broccoli, Brussels sprouts, cauliflower, lettuce and cabbage Pungent and bitter vegetables such as broccoli, cabbage, Brussels sprouts, aubergine and lettuce
Oats, rice and wheat Barley, oats and rice Barley, oats, corn, millet, basmati rice
Beef, chicken and eggs Chicken and eggs Chicken and eggs
No legumes All legumes except lentils All legumes except kidney, soya and mung beans
All nuts in small quantities No nuts except coconuts No nuts
All seeds in small amounts No seeds but for sunflower and pumpkin No seeds except sunflower and pumpkin
All natural sweeteners but not white sugar All natural sweeteners but not molasses or honey Raw honey only
All spices Coriander, turmeric, fennel, cinnamon and cardamom All spices except salt
All dairy products Unsalted butter, cottage cheese and milk No dairy products except goat’s milk
All oils Coconut, sunflower and olive oils Almond, corn, sunflower oils in small amounts

Finally it is important to emphasise that the use of foods in Chinese and Ayurvedic medicine is different from the modern nutritional use of foods, which is based on understanding the vitamin, mineral, protein, phytochemical, carbohydrate and fat content. In Chinese or Ayurvedic medicine foods are understood in terms of taste - whether they are sweet, bitter, sour, pungent or salty - and whether they are warming, cooling or neutral in their affect on the body. The opposite quality to the condition is always chosen, hence for someone with coldness in the body, warming foods are used, whilst if someone is weak and deficient, sweet tasting foods which are strengthening are used.


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Edward Thompson has 11 years of training in natural medicine. He is a herbalist practising both Western and Chinese herbalism, an acupuncturist, homeopath, shiatsu and craniosacral practitioner and has studied Ayurveda at the Ayurvedic Institute in London with Dr Vasant Lad.



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