The metabolic disorder of body fluids is the last fundamental pathogenesis. Recently, the weather has been quite dry, and many friends around me often experience symptoms such as dry mouth, peeling skin, and tightness in the face. Even drinking plenty of water does not alleviate these symptoms. This is a manifestation of abnormal body fluid metabolism, which in Traditional Chinese Medicine (TCM) is referred to as “deficiency of body fluids” (jinye queshi), and it is necessary to replenish body fluids to relieve these symptoms.
What are body fluids?
In TCM, “body fluids” (津液, jinye) refer to all the water and liquid substances within the human body, including the internal fluids and normal secretions of the organs, such as gastric juice, intestinal fluid, saliva, urine, sweat, tears, and nasal mucus. Body fluids are extremely important as they nourish and moisten the body. For example, ancient people often referred to saliva as “the water of the Huachi” or “the jade spring,” believing that saliva has health-preserving benefits. Additionally, body fluids can also generate blood, regulate the balance of yin and yang in the body, and play a role in maintaining health. In Zhang Zhongjing’s “Shanghan Lun,” an important academic thought is discussed, which emphasizes the preservation of body fluids.
Among body fluids, those that are relatively clear and fluid, distributed on the surface of the skin, muscles, and orifices, and can penetrate into the blood vessels to provide moisture, are called “jin” (津); while those that are thicker, less mobile, and permeate the joints, organs, brain, and marrow, providing nourishment, are called “ye” (液).
The normal metabolism of body fluids is a fundamental condition for maintaining the relative balance between the generation, distribution, and excretion of body fluids. Abnormal metabolism of body fluids occurs when there is a disruption in the distribution of body fluids, leading to an imbalance between the generation and excretion of body fluids, resulting in insufficient generation of body fluids, or abnormal distribution and excretion, causing slow circulation of body fluids within the body, leading to pathological changes such as fluid retention, stagnation, and overflow.
The metabolism of body fluids in the human body is a complex physiological process that requires the coordination of various physiological functions of multiple organs to maintain normal metabolic balance. From the perspective of the five organs, the metabolism of body fluids is most closely related to the lungs, spleen, and kidneys. Therefore, any abnormality in any organ or any physiological function in the lungs, spleen, or kidneys can lead to abnormal metabolism of body fluids, resulting in insufficient body fluids or retention of body fluids within the body, leading to the internal generation of dampness or phlegm.
Insufficient Body Fluids
Insufficient body fluids refer to a deficiency in the quantity of body fluids, which leads to the internal organs and external orifices and skin losing their moistening and nourishing functions, resulting in a series of pathological changes characterized by dryness. What causes insufficient body fluids? One cause is the invasion of external dryness or heat, or the fire of the five emotions. Additionally, high fever, excessive sweating, vomiting, diarrhea, frequent urination, blood loss, or excessive consumption of drying herbs can also lead to the depletion of body fluids.
Insufficient body fluids can be likened to a machine that lacks lubrication during operation, causing it to run roughly and produce friction sounds. It is also similar to a plant that has been exposed to the sun for several days without timely watering, causing it to shrivel and lose vitality. What are the manifestations? For example, dry skin, dry corners of the eyes, dry mouth, and dry tongue. If it occurs in the late stage of a febrile disease or after a prolonged illness that injures yin, it may present as a bright red tongue with little or no coating, dry lips and tongue, dry and withered skin and hair, and even tremors or spasms in the hands and feet, which are clinical manifestations of yin fluid depletion and wind movement.
For instance, some elderly individuals may experience sudden hand and head tremors before menstruation, which is not Parkinson’s disease but rather due to insufficient body fluids. Since the liver governs the tendons, if liver blood is insufficient, it cannot nourish the tendons, leading to spasms. Nourishing body fluids with herbs such as Sha Shen (Glehnia root), Mai Dong (Ophiopogon), and Sheng Di Huang (Rehmannia) can quickly alleviate the tremors.
Generally speaking, mild cases are classified as injury to body fluids, while severe cases are classified as injury to yin. Injury to body fluids does not necessarily accompany injury to yin, but injury to yin will certainly involve injury to body fluids. Therefore, injury to body fluids is a gradual injury to yin, while injury to yin is a severe depletion of body fluids.
Water and Dampness Stagnation
Water and dampness stagnation occurs when there is a problem with the distribution and excretion of body fluids, resulting in abnormal stagnation of body fluids within the body, leading to the internal generation of dampness, phlegm, and other pathological products.
The obstruction of body fluid distribution refers to the inability of body fluids to be distributed normally, leading to slow circulation of body fluids within the body or retention in a specific area, causing body fluids to not transform, resulting in the internal generation of dampness and the formation of phlegm. The normal distribution of body fluids involves the lung’s ability to disperse and descend, the spleen’s ability to transport and transform, the liver’s ability to regulate and smooth, and the patency of the water pathways of the San Jiao (Triple Burner). Among these, the most critical is the spleen’s transport function. As stated in the “Suwen: Zhenzhen Yaodalu,” “All dampness and swelling belong to the spleen.”
Water and dampness stagnation primarily leads to pathological changes such as dampness obstruction, phlegm accumulation, and fluid retention.
1. Dampness Obstruction
Dampness obstruction is mainly caused by the spleen’s inability to transport dampness. Dampness is a familiar concept, and we have discussed it extensively before. After dampness obstruction, many symptoms may arise.
If dampness obstructs the clear orifices, symptoms such as dizziness, nasal congestion, lack of energy, and frequent yawning may occur, making it difficult to concentrate at work.
If dampness obstructs the middle burner, causing internal stagnation, the spleen loses its healthy transport function, leading to abdominal distension and fullness, resulting in either weight gain or failure to gain weight.
In the lower burner, if dampness flows down, symptoms such as loose stools or even diarrhea may occur. This is commonly seen in summer and autumn when temperature fluctuations lead to gastrointestinal colds!
Therefore, TCM states that dampness is a common ailment, “its harm is the slowest, most hidden, and hardest to detect.”
2. Phlegm Accumulation
Phlegm and fluid are pathological products formed due to organ dysfunction and body fluid metabolism disorders, leading to the accumulation of dampness and phlegm, which are factors in various diseases, resulting in complex pathological changes.
Phlegm accumulation primarily involves the lungs, stomach, and heart. Dysfunction in these organs can lead to phlegm accumulation and a series of pathological changes. For example, if phlegm obstructs the lungs, symptoms such as cough, wheezing, and phlegm production may occur; if phlegm obstructs the heart, it can lead to chest tightness, palpitations, and mental confusion; if phlegm accumulates in the stomach, it can cause nausea, vomiting, and discomfort in the epigastric region, leading to a feeling of fullness and discomfort; if phlegm obstructs the meridians and muscles, it can lead to lumps, numbness in the limbs, hemiplegia, and yin sores. Lumps are similar to what Western medicine refers to as lymph node tuberculosis, with lymph nodes resembling a string of beads. Phlegm lumps can resemble cysts under the skin. Yin sores refer to cold phlegm stagnating in the meridians and muscles, resulting in non-red, non-swollen, and non-painful skin ulcers. Stagnation refers to the presence of a fistula connecting one end to the other, discharging white or yellow pus. Phlegm turbidity affecting the head can cause dizziness and fainting, while phlegm obstructing the throat can lead to a sensation of a lump in the throat, similar to what Western medicine calls chronic pharyngitis. Patients may feel as if there is something stuck in their throat that they cannot swallow or spit out, which TCM refers to as “plum pit qi.” Fluid accumulation in the chest and ribs is called “suspended fluid,” similar to pleurisy, where fluid accumulates in the pleural cavity. Fluid accumulation in the chest is called “branch fluid,” commonly seen in bronchitis and pneumonia. Fluid retention in the limbs is called “overflowing fluid,” similar to edema. These are all pathological manifestations of phlegm accumulation.
3. Fluid Retention
In TCM, the metabolism of body fluids is related to all the organs, with the kidneys and spleen being the most relevant. Kidney yang and spleen yang are the driving forces behind body fluid metabolism. When the kidneys cannot govern water and the spleen cannot transport dampness, fluid retention occurs, leading to diseases such as edema. If fluid overflows into the skin, symptoms such as facial, eyelid, and limb swelling, or even generalized edema may occur. If water stagnates in the abdominal cavity, it can lead to abdominal distension and ascites.
For example, I once treated a woman in her thirties who experienced premenstrual swelling, but her menstruation was normal. Upon examination, her tongue coating was yellow, her face was swollen, her body was plump, and her complexion was pale; her pulse was wiry and slippery. This pattern of premenstrual swelling indicates spleen deficiency with excess dampness. Therefore, our treatment focus should be on strengthening the spleen and transforming dampness, and after a period of treatment, her condition returned to normal.
The disorders caused by the obstruction of body fluid distribution and excretion are illustrated in the image below:
Disruption of the Relationship Between Body Fluids and Qi/Blood
The disruption of the relationship between body fluids and qi/blood is commonly seen clinically in aspects such as water stagnation causing qi obstruction, qi escaping with fluid loss, body fluids drying up leading to blood dryness, and body fluid deficiency leading to blood stasis.
1. Water Stagnation Causing Qi Obstruction
Water stagnation causing qi obstruction is a pathological change where water and fluids accumulate in the body, leading to qi stagnation. The liver governs the smooth flow of qi and participates in the regulation of body fluid metabolism, emphasizing that when qi flows, water flows; when qi stagnates, water stagnates. During body fluid metabolism, the accumulation of dampness can obstruct the flow of qi, leading to qi stagnation, with both being mutually causal, ultimately resulting in the pathological outcome of qi stagnation and water stagnation.
Clinical manifestations are related to the location of water and fluid stagnation. For example, if water and fluid obstruct the lungs, it can lead to lung qi stagnation, resulting in symptoms such as chest fullness, cough, and difficulty lying flat; if water and fluid obstruct the heart, it can suppress heart qi, leading to palpitations and chest pain; if water and fluid stagnate in the middle burner, it can obstruct the spleen and stomach qi, causing clear qi to fail to rise and turbid qi to fail to descend, resulting in symptoms such as dizziness, fatigue, abdominal distension, and nausea; if water and fluid stagnate in the limbs, it can obstruct the flow of qi and blood in the meridians, leading to not only swelling but also heaviness or pain in the limbs.
2. Qi Escaping with Fluid Loss
Qi escaping with fluid loss refers to a pathological change where a large loss of body fluids leads to the loss of qi, resulting in both qi and yin being depleted. This condition is often caused by excessive sweating, severe vomiting, or diarrhea, which depletes body fluids.
The ultimate result of qi escaping with fluid loss is the depletion of both qi and yin. For example, in acute gastroenteritis, severe vomiting and diarrhea can lead to dehydration, with the vomited contents being watery and the stools being watery as well. The eyes may become sunken, skin elasticity may be lost, and weight loss may occur, indicating a rapid loss of body fluids. This significant and rapid loss of fluids can also lead to symptoms such as mental fatigue and weakness, characteristic of qi deficiency. In severe cases, there may be coldness in the hands and feet, and a weak pulse, indicating extreme qi deficiency and the stage of yang collapse. TCM treatment for shock caused by significant dehydration focuses on restoring qi.
3. Body Fluids Drying Up Leading to Blood Dryness
Body fluids drying up leading to blood dryness refers to a condition where body fluids are deficient or even exhausted, resulting in the internal generation of heat or wind due to blood dryness. Body fluids serve as a conduit for the distribution of fluids throughout the body and are also an important component of blood. If body fluids are deficient, the blood vessels become empty, leading to body fluids drying up and blood becoming dry. The causes of body fluid deficiency often include high fever, burns, or yin deficiency with heat.
Clinical manifestations may include irritability, dryness of the nasal passages and throat, thirst with a preference for drinking, muscle wasting, scanty urination, a red tongue with little moisture, and a thin, rapid pulse.
4. Body Fluid Deficiency Leading to Blood Stasis
Body fluid deficiency leading to blood stasis refers to a pathological change where the deficiency of body fluids results in poor blood circulation. Adequate body fluids are essential for maintaining the fullness of blood vessels and the smooth flow of blood. If high fever, excessive sweating, or other factors lead to a significant loss of yin fluids, the components involved in blood formation will decrease, affecting the speed of blood circulation and leading to blood stasis.
Clinical manifestations may include purple or dark red tongue body or the presence of petechiae, which is the reason for the appearance of blood stasis on the skin after significant damage to body fluids.
Starting from the “Bladder”: What is the Bladder?
Many TCM textbooks explain: “The bladder is the organ that stores and excretes urine… located in the lower abdomen… connected to the kidneys by the ureters above and opens to the front via the urethra. The physiological function of the bladder is to store and excrete urine.” How does this explanation differ from Western medicine? As an introductory course in TCM, how can students learn the “Huangdi Neijing” or “Shanghan Lun” and guide clinical practice with such explanations? Is this what is meant by integrating Chinese and Western medicine or modernizing TCM? Such explanations can only destroy TCM.
So what exactly is the bladder? Before addressing this question, it is necessary to understand the characteristics of TCM concepts. TCM research methods involve observation and introspection, and its concepts reflect more of a function rather than anatomical structure. For example, “the sky is round and the earth is square,” the four seasons, day and night, the function of the sky is indeed round, right? The concept of TCM organs, meridians, qi, blood, and body fluids is more about function rather than just anatomical structure. This is also the reason why meridians cannot be found under a microscope.
Once we understand the characteristics of TCM concepts, we can explore what the bladder is. The “Suwen: Linglan Mijian Lun” states: “The bladder is the official of the state, where body fluids are stored; when qi transforms, it can be released.” This indicates that the bladder stores body fluids, and that body fluids can be released when qi transforms. What does “qi transformation leads to release” mean? Many people often say “bladder qi transformation is not smooth” when explaining issues related to urination, using formulas such as Shen Qi Wan, Wu Ling San, or Zhen Wu Tang. This suggests that bladder qi transformation is related to kidney yang. This is also mentioned in the “Selected Readings of Huangdi Neijing.” But is this the whole story? I believe it is not entirely so.
As previously mentioned, TCM concepts are more about function. The statement that the bladder “stores body fluids” (not urine) indicates that the bladder is a reservoir for body fluids, akin to a water reservoir.
What does “qi transformation leads to release” mean? There are two aspects to “release”:
One is the clear yang portion, which, after transformation, nourishes the organs, tissues, and orifices, spreads to the skin, and circulates through the five organs and meridians;
The other is the turbid yin portion that is released through the lower orifices, which is urine.
So where does the clear yang portion go after it is released from the bladder?
The water from the reservoir naturally flows into the waterways, and the San Jiao is the waterway.
The “Suwen: Linglan Mijian Lun” states: “The San Jiao is the official of drainage, where the waterway is released.” (Here, San Jiao refers to the San Jiao as one of the six fu organs, the same applies below.)
What does it mean that the San Jiao governs qi and manages drainage?
Qin Bomei explains that the San Jiao’s qi mechanism must be smooth for body fluids to be distributed and transformed, thus managing drainage. This explanation is correct, but I believe it is not comprehensive. The term “governing qi” here refers not only to the qi mechanism but also to qi transformation (of course, the qi mechanism is the basis for qi transformation).
What exactly is San Jiao qi transformation, and what is bladder qi transformation?
First, let’s look at the relationship between the San Jiao and the bladder. The “Lingshu: Ben Shu” states: “The San Jiao is the official of the middle drainage, where the waterway is released, belonging to the bladder, which is the official of the state.” What does it mean that the San Jiao belongs to the bladder? Think of it this way: the waterway belongs to the reservoir.
The bladder, this reservoir, is located in the lower burner, but the San Jiao, this waterway, is formless and pervades the entire body (to some extent, wherever there is body fluid, it belongs to the bladder and San Jiao). Bladder qi transformation is closely related to kidney yang but also significantly related to the lungs and spleen. The San Jiao pervades the entire body, with the lungs facilitating its qi transformation above, the spleen facilitating its qi transformation in the middle, and the kidneys facilitating its qi transformation below. Of course, it is also related to the liver and heart.
Thus, the “Classified Classics: Zang Xiang” states: “If the upper burner is not treated, water will overflow the high plains; if the middle burner is not treated, water will remain in the middle; if the lower burner is not treated, water will disrupt the two excretions.”
The bladder “qi transformation leads to release.” The term “release” refers to two aspects: (1) the excretion of urine (which can be abnormal in two ways: either not excreting or excreting excessively), and (2) the release from the bladder to the San Jiao, where it undergoes qi transformation, allowing “water essence to be distributed” to nourish the body, and “five meridians to operate” within the organs and meridians. Of course, body fluids also undergo qi transformation as they pass through the bladder and San Jiao, allowing “water essence to be distributed and the five meridians to operate.” During the qi transformation in the upper burner, body fluids are excreted in the form of sweat, hence it is said that “the San Jiao and bladder respond to the skin and hair” (“Lingshu: Ben Zang”).
Once we truly understand the bladder and San Jiao, we will find that the two are closely related in function. Therefore, it is said that “the San Jiao belongs to the bladder.” In summary, bladder qi transformation releases body fluids to the San Jiao, and San Jiao qi transformation distributes body fluids throughout the body, but both rely on the lungs, spleen, kidneys, and liver. That is, the body fluids in the bladder and San Jiao undergo qi transformation to distribute throughout the body, irrigating the meridians and organs, while some are excreted as urine, sweat, or through breathing. However, there are still differences between the two; think of the difference between a reservoir and a water channel, or between the ocean and rivers, and combine this with various diseases to understand.
Diseases related to body fluids are all caused by the dysfunction of bladder and San Jiao qi transformation, whether due to deficiency or excess, ultimately relating back to this. The qi mechanism is also the basis for qi transformation, so the qi mechanism must not be forgotten. If dampness, phlegm, fluid, wind, cold, or heat obstruct the qi mechanism, we must guide their removal according to the situation, whether through sweating, urination, or purging.
What does fluid stagnation mean?
Fluid stagnation refers to the disorder or obstruction occurring in the generation, distribution, and excretion of body fluids. It is primarily manifested as the deficiency of body fluids and the pathological changes of distribution and excretion obstruction.
1. Spleen’s Inability to Transport, Water and Fluid Stagnation.
The spleen governs transportation, allowing water and fluids to ascend to the lungs and distribute throughout the body, while also nourishing the kidneys and bladder. If diet, overwork, or external dampness injures the spleen, or if the spleen qi is internally obstructed, leading to impaired spleen function, qi transformation will be disrupted, and water and fluids will stagnate, resulting in disease. As stated in the “Suwen: Zhenzhen Yaodalu,” “All dampness and swelling belong to the spleen.”
2. Lung’s Inability to Regulate, Water Overflowing.
The lungs govern the regulation of water pathways and are the source of water. If they can regulate the water pathways, body fluids can be distributed throughout the body to perform their nourishing functions and can also descend to the bladder to excrete excess fluids and turbid qi. If external pathogens invade the lungs, lung qi will fail to disperse and descend, leading to stagnation of body fluids in the upper burner, overflowing throughout the body, or accumulating as phlegm.
3. Kidney’s Inability to Transform, Water and Fluid Stagnation.
The kidneys are the residence of water and fire, the root of yang qi. The original yang in the kidneys transforms body fluids into liquid, serving as the driving force for the qi transformation of all organs. At the same time, the kidneys and bladder are interrelated; the bladder stores body fluids, and when qi transforms, it is released as urine. If there is congenital deficiency, acquired imbalance, or prolonged illness affecting the kidneys, leading to insufficient kidney yang, qi transformation will be impaired, and body fluids will fail to ascend, resulting in insufficient yang qi in the organs, impaired qi transformation, and abnormal urination.