Jing (Chinese medicine)

Jīng (Chinese: 精; Wade-Giles: ching¹) is the Chinese word for "essence", specifically kidney essence. Along with qì and shén, it is considered one of the Three Treasures Sanbao 三寶 of Traditional Chinese Medicine or TCM.

According to tradition, Jīng is stored in the kidneys and is the most dense physical matter within the body (as opposed to shén which is the most volatile). It is said to be the material basis for the physical body and is yīn in nature, which means it nourishes, fuels, and cools the body. As such it is an important concept in the internal martial arts. Jīng is also believed by some to be the carrier of our heritage (similar to DNA). Production of semen, in the man, and menstrual blood (or pregnancy), in the woman, are believed to place the biggest strains on jīng. Because of this, some even equate jīng with semen, but this is inaccurate; the jīng circulates through the eight extraordinary vessels and creates marrow and semen, among other functions.

Jīng (精; essence) should not be confused with the related concept of jìn (勁; power), nor with jīng (經; classic/warp), which appears in many early Chinese book titles, such as the Nèi Jīng, yì jīng and Chá Jīng, the fundamental text on all the knowledge associated with tea.

The characteristics which constitute signs of good Jing (e.g. facial structure, teeth, hair, strength of adrenals or kidneys) share the embryological origin of neural crest cells. These cells undergo immense and challenging cellular migrations requiring great organisation. As such, Jing may simply represent the strength of embryological self-organisation in the organism. This will be manifestated most strongly in those cells which require most organisation; that is, the neural crest cells.

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