Jing (essence) - juice - puts the "sauce" in saucy

1. Kidney Jing plays important role in physiology.
2. Is hereditary, like Prenatal Jing and determines constitution.
3. However, is partly replenished by the Postnatal Jing.
4. Stored in the Kidneys but has fluid nature and circulates all over the body, especially in the Eight Ancestral (Extraordinary) Vessels.
5. Forms the basis for growth, development, sexual maturation, and reproduction.
6. Moves in long, slow cycles, and presides over the major phases of development in life.
   
   
   1. The first is in childhood. Kidney Jing controls growth of bones, teeth, hair, brain development and sexual maturation. Where Kidney Jing is weak, there may be poor bone and teeth development, stunted growth, and mental retardation.
   2. Puberty. Kidney Jing controls reproductive function and fertility, and normal development into adulthood. Developmental problems that occur at this time such as amenorrhea, are often related to weak Kidney Jing.
   3. Conception and pregnancy are guided and controlled by Kidney Jing. Where Kidney Jing is weak, signs such as infertility, chronic miscarriage and other such problems may occur.
   4. Kidney Jing declines naturally, finally producing the characteristic signs of hair/teeth loss, impairment of memory, etc.
7. Kidney Jing is the basis for Kidney Qi
   
   Jing is fluid-like and therefore more Yin. Can be considered as an aspect of Kidney Yin.
   
   Forms the material basis for production of Kidney Qi (via the warming action of Kidney Yang. Kidney Yin is warmed by Kidney Yang and Kidney Qi is formed, but Kidney Jing is necessary before this transformation can occur.
   
   Deficiency of Kidney Jing can thus result in such problems as impotence, chronic weak or sore lower back, weak knees, tinnitus, urinary incontinence, deafness, loose teeth, etc. (all signs of weak Kidney Qi and/or Yang.)
8. Kidney Jing produces Marrow
   
   Kidney Jing produces Marrow. Marrow produces bone marrow, the brain, and the spinal cord (Marrow in TCM has no exact equivalent in Western Medicine).
   
   The Brain in TCM is called the "Sea of Marrow". Therefore if Kidney Jing is weak, brain may be undernourished, leading to poor memory/concentration, "empty" feeling in the head, dizziness, etc.
9. Kidney Jing determines our Constitution
   
   Our protection from exterior pathogens depends largely on the strength of a type of Qi: the Defensive (Wei) Qi.
   
   However, the state of Kidney Essence also influences our strength and resistance. If the Essence is "wasted" or poorly stored, the person may have lowered immunity to exogenous pathogenic influences and constantly be ill with cold, influenza, allergies, etc.
10. Essence and Qi are the material foundation for Shen (Mind).

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