Relationships with the internal organs

The internal organs and body fluids: a network of cooperation

Body fluids are not produced and managed by a single organ. In Traditional Chinese Medicine they are the result of coordinated activity involving several organs, each contributing a specific function to transformation, transportation and excretion. Understanding this network is essential for interpreting fluid pathology and for determining which underlying organ systems require treatment.

The Spleen: the primary organ of transformation

The Spleen occupies the most central position in fluid physiology. It performs the first and most decisive stage: transforming ingested food and drink and separating the pure from the impure. Without adequate Spleen function, the other organs cannot carry out their fluid-related roles effectively because the Spleen provides the transformed material they must work with.

The Spleen also governs the correct direction of fluid movement. The pure should rise and the impure should descend. When Spleen function becomes weak, this directional control deteriorates. Fluids may accumulate, Dampness may develop, Phlegm may form and oedema may appear. This explains why strengthening or regulating the Spleen is frequently relevant in disorders of body fluids, even when another organ is also involved.

The Lung: regulator of the Water Passages

The Lung has two complementary functions in fluid metabolism. Through its dispersing function it spreads the pure fluids received from the Spleen toward the space beneath the skin and the peripheral tissues. Moistening of the skin and regulation of perspiration are direct expressions of this function.

Through its descending function, the Lung sends fluids downward toward the Kidneys and Bladder. Because it both disperses and descends fluids, TCM says that the Lung regulates the "Water Passages". Weak Lung function may therefore be associated with dry skin, dry cough or, conversely, accumulation of fluids in the upper part of the body.

The Kidneys: the source of warmth for fluid transformation

The Kidneys, and particularly Kidney Yang, regulate fluid metabolism at the deepest level. Kidney Yang provides the warming force required for transformation. Without sufficient Kidney Yang, the Spleen cannot transform effectively, the Small Intestine cannot separate properly and the Bladder cannot perform its Qi transformation.

The Kidneys also transform part of the fluids into a fine vapour that is sent upward to moisten the Lungs. This represents an important reciprocal relationship between Lung and Kidney. Kidney Yang deficiency is therefore one of the important traditional patterns associated with oedema and fluid retention.

The Small Intestine, Bladder and Triple Burner

The Small Intestine performs another stage of separation. It distinguishes the relatively pure part of the fluids, which proceeds toward the Bladder, from the impure portion that continues toward the Large Intestine. This separating function is supported by Kidney Yang, which supplies warmth and Qi.

The Bladder receives fluids from the Small Intestine and Kidneys and performs a further separation of pure and impure. Through Qi transformation it participates in the formation and excretion of urine.

The Triple Burner is not an anatomical organ in the Western sense but a functional system coordinating the Upper, Middle and Lower Burners. It supports fluid transformation, transport and excretion throughout the body and provides the functional pathways through which Yuan Qi and fluid processes operate.

The Stomach: the quiet source

The Stomach is sometimes overlooked in fluid physiology, yet it can be regarded as an essential source of the body fluids because food and drink are first received there. The Stomach prepares the ingested material and passes it to the Spleen for transformation and separation. If the Stomach cannot receive and process food and drink properly, the entire production of fluids is compromised.

Conclusion: treat the system, not only the symptom

Fluid metabolism in TCM is a network of mutually dependent organ functions. Dry eyes may relate to Liver Blood deficiency, ankle oedema may relate to Kidney Yang deficiency and dry cough may relate to Lung Yin deficiency. Yet the Spleen remains an important central regulator in the broader fluid system. A practitioner therefore evaluates the whole network rather than treating only the visible manifestation.