Traditional Chinese medicine (TCM) is built on a foundation of more than 2,500 years of Chinese medical practice. TCM is a holistic practice that aims to treat the body as a whole, rather than alleviate specific symptoms of illness.

Within TCM, there is frequent discussion of substances called Essence, Qi, Blood, and Body Fluid.  What’s the relationship Between Essence, Qi, Blood, and Body Fluid?

Qi is active by its very nature. It is categorized as yang (bright) and is responsible for warming the body. Blood is also active in nature, but is categorized as yin (dark), and is responsible for nurturing the body.

Qi is the primary driving force for the formation and subsequent movement of blood. Blood metaplasia is formed by qi and blood is its subsequent carrier within the body.

1. Qi can produce body fluid
   The movement and change of qi are the driving force for the metaplasia of body fluid and the abundance of qi in the spleen, stomach, and other viscera guarantees sufficiency for the metaplasia of body fluid.
2. Qi can move body fluid
   The movement and change of qi are the driving force for the distribution and excretion of body fluid (when qi moves, fluid moves).
3. Qi can control body fluid
   The proper solidification and dilution effect of qi can prevent the indiscriminate loss of body fluid and monitor the excretion of sweat and urine in a controlled manner.

1. Body fluid can generate qi
   The nourishment and replenishment of body fluid can make the spleen, stomach, lungs, kidneys, and other viscera function vigorously, and in turn help the metaplasia of qi.
2. Body fluid can carry qi
   Body fluid is another carrier of qi around the body. And as qi is embedded within the body fluid, it can move around without being lost through vaporization.

1. Physiological relationship between blood and body fluid
   Blood and body fluid are mutually convertible and mutually complementary between themselves.
2. Pathological relationship between blood and body fluid
   In the context of pathology, body fluid and blood lesions can affect each other.

The intimate relationship between qi and essence is manifested in the way that qi can generate essence, and essence can transform into qi.

The relationship between blood and essence lies in the fact they originate from the same source so one can generate the other, and vice versa.

For body fluid and essence, it is due to their co-relationship with water and grain, from which both originate, and are then produced in the spleen and stomach. Therefore, the essence of water and grain and body fluid bears the distinct co-generation and assimilation relationship.