There are two types of body fluids in Chinese medicine:
Fluids in Chinese are called Jin
Liquids in Chinese are called Ye
These fluids are clear, light and thin watery, and they circulate with Defensive Qi on the exterior (skin and muscles). They move relatively quickly. They are under the control of the Lungs, which spreads them to the skin all over the body.
Their function is to moisten and partially to nourish the skin and muscles. They are the fluids that are exuded as sweat. They also manifest as tears, saliva and mucus.
Another important function of Jin fluids is to become a component of the fluid part of the blood. These fluids thin the blood out and prevent its stasis.
These liquids are more turbid, heavy and dense. They circulate with the nutritive Qi in the interior. They move relatively slowly. They are under the control of the Spleen and Kidneys for their transformation.
Their function is to moisten the joints, spine, brain and bone marrow. They also lubricate the orifices of the sense organs, i.e. eyes, ears, nose and mouth.
Relation between Qi and Body Fluids
- Qi transforms and transports fluids. Without the transforming and transporting power of Qi, body fluids would accumulate giving rise to disease.
- Qi holds Body Fluids in. If Qi is deficient, the fluids may leak out as incontinence or enuresis (Kidney Qi deficiency), spontaneous sweating (Lung Qi deficiency), or vaginal discharge (Spleen Qi deficiency).
- Body Fluids play a minor part in nourishing Qi. After a significant loss of fluids, such as occurs in profuse sweating, Qi also becomes deficient. Another example is Excessive vomiting that depletes the Qi.
Relation between Blood and Body Fluids
There is mutual nourishment between fluids and blood. On one hand, Body Fluids constantly replenish Blood and make it thinner so that it does not coagulate or stagnate. On the other hand, Blood can also nourish and supplement Body Fluids. Both Blood and Body Fluids pertain to Yin and are somewhat interchangeable. For this reason, if there is a significant loss of Body Fluids over a long period of time, as in chronic spontaneous sweating or excessive use of saunas, this can lead to deficiency of Blood. Vice versa, if there is a chronic loss of blood, as in menorrhagia, this can lead to deficiency of Body Fluids and dryness. Because Blood and Body Fluids come from the same source and mutually nourish each other, sweating and bleeding treatment methods are contradictory in practice, and should never be used together.