From a physiological point of view, Kidney Energy governs reproduction, growth and the development of the body. It rules the bones and produces the marrow. It is responsible for the metabolism of fluids and is the driving force behind all physiological processes, including the action of warming. It stores what we call innate and acquired Jing. It also receives the Energy of the Lung and controls mental activity, memory and concentration.
Hair, bones, marrow, teeth, the spine, the brain, the sexual organs and the ears are all part of the Kidney energy system.
According to TCM, Kidney functions are deficient in cases of oedema, fragile bones, stiff or painful joints, chronic fatigue, lower back weakness, sensitivity to cold, deep low-pitched tinnitus, deafness, wrinkled dry skin, early loosening of the teeth, needing to urinate several times at night, high blood pressure (salt-free diet), early morning diarrhoea, vaginal dryness, cystitis, low libido, premature ejaculation, impotence, infertility, prostate problems, and decline of physical and/or mental faculties.
From an emotional point of view, Kidney Energy plays a role of command and execution, of will (ZHI) and of creation. The memories held in the deep unconscious are also part of it. An imbalance in Kidney Energy can show up as excessive fears or phobias and a lack of courage. On the contrary, self-confidence, a sense of inner calm, boldness and resilience are all signs of vigorous Kidney energy.
The foods traditionally recommended in Chinese dietetics to tone Kidney Energy are:
Seaweed, legumes, chestnuts, red beans, adzuki, lentils, tofu, tempeh, miso soup, shiitake, beef, duck, chicken, lamb, kidneys, shrimp, walnuts, black pepper, chili, cinnamon, ginger, nutmeg, black sesame.
Activities should be both dynamic and restorative so as not to exhaust the Kidneys, such as hiking, yin yoga or tai chi.