What is deficiency? Deficiency means weakness. Yang deficiency means fire is weak, and Yin deficiency means water is weak. In the human body, what is Yang and what is Yin? Or what is fire and what is water? People eat and breathe in oxygen, and through the biological transformation of the stomach and intestines, energy is produced, and this energy is the fire of the human body, the fire of life, which is the Yang of the human body. What is the yin of the human body, or the water of the human body? This water is the blood, the body fluids. Just like boiling water and cooking, if the fire is too big, the water will burn dry and the rice will burn; likewise, if the fire is not enough, the water will not boil and the rice will not be cooked. The human body is the same, if a person’s yang is not enough, people will not be transported well, people will be wet and heavy, the body is fat, the tongue is fat, the stool is not formed; conversely, if a person is not enough yin, people will look very thin, and easy to dry mouth and constipation. Therefore, in general, fat people are more Yang deficient, while thin people are more Yin deficient. Therefore, only a person with a balanced yin and yang will not be fat or thin, and will look proportionate. The interrelationship between kidney yin and kidney yang: kidney yin and kidney yang are two aspects of kidney physiology. The role of nourishing all the internal organs of the body is called kidney yin; the role of promoting the activities of all the internal organs of the body is called kidney yang. The nature of the two is different, Yin and Yang, cold and heat, are two opposing aspects. But the two coexist in the kidneys and are specific manifestations of kidney essence and kidney qi, and are closely linked and inseparable. Yin fluid needs to rely on Yang Qi for propulsion, and Yang Qi needs Yin fluid as its foundation. Kidney Yang deficiency and Kidney Yin deficiency are both Kidney deficiency, the difference lies in the presence or absence of obvious cold or heat symptoms. Kidney yin: Kidney yin is the embodiment of kidney essence, and all the internal organs of the body depend on kidney yin for nourishment; it is the root of the body’s yin fluid, so it is also called “yuan yin”. The loss of nourishment of kidney yin in the internal organs of the human body will lead to pathological changes, such as the loss of nourishment of the liver will lead to liver yin deficiency, liver Yang hyperactivity, and even liver wind; the loss of nourishment of the heart will lead to heart yin deficiency, heart fire, heart trouble and insomnia; the restlessness of the mind; the loss of nourishment of the brain will lead to vertigo and tinnitus. In turn, a serious deficiency of yin in the internal organs will also lead to a deficiency of kidney yin, such as heat aggression burning the stomach, stomach yin deficiency, further damage to kidney yin, called “kidney yin dry”. Due to “Yin deficiency leads to Yang hyperactivity” and “Yin deficiency leads to internal heat”, Kidney Yin deficiency often results in signs of deficiency heat such as hot flashes, rising fire, red cheek, red tongue, dry mouth and throat, and weak pulse. If there is deficiency without heat, it is called kidney essence deficiency. Kidney Yang: Kidney Yang drives the physiological activities of the internal organs of the body and is the root of all Yang energy, also called “Yuan Yang”. Insufficient kidney yang will affect the physiological activities of the internal organs and cause pathological changes. If the lungs lose the help of kidney yang, there will be shortness of breath and lack of inhalation, which is called kidney non-gas; if the spleen loses the impetus of kidney yang, there will be diarrhea and lack of transformation of finished grain; if the heart loses the encouragement of kidney yang, there will be palpitations, shortness of breath, chest tightness, blue lips and tongue and other symptoms of heart yang deficiency; if the bladder loses the qi of kidney yang, there will be unfavorable urination or incontinence or incomplete urination; if the absorption and transmission of fluid lose the qi of kidney yang, edema will occur; If the kidney yang fails, there are dangerous symptoms such as pallor, cold extremities, cold sweat like oil, and weak pulse, which are called dead yang. “Yang deficiency is Yin Sheng”, “Yang deficiency produces external cold”. Kidney yang deficiency will inevitably produce cold signs, such as cold walking limbs, light complexion, cold pain in the back and spine, preference for hot drinks, clear and long urine, thin stool, pale tongue with white fur, and other symptoms. If the deficiency is not obvious, it is generally called “kidney qi deficiency”. Kidney qi deficiency refers to the deficiency of kidney qi, which is the result of the failure of the function of sealing and fixing. It is often caused by congenital deficiency of endowment or long term illness and strain that injures the kidney qi. Clinical manifestations are: soreness and weakness of the waist and knees, fatigue, tinnitus, frequent and clear urination, or incomplete residual urination, or nocturnal urination, or enuresis, or urinary incontinence; or slippery sperm in men, premature ejaculation; or diluted belt in women, easy slippage of the fetus, with a weak tongue and sunken pulse. The kidneys store essence, the main growth, development and reproduction. Insufficient kidney essence leads to infertility in men, menstrual shutdown and infertility in women, dizziness, diminished vision, tinnitus and deafness, mental fatigue, sore and tired bones, shaky teeth and hair, lazy limbs, seminal emission, pale white color, large and weak pulse, and fat and pale tongue. Kidney essence is transformed into kidney qi. Insufficient kidney essence, which does not transform into qi, can lead to kidney qi deficiency; while kidney qi deficiency is mainly manifested by weakness of kidney functions, if further development is accompanied by cold symptoms such as fear of cold, it is kidney yang deficiency, and kidney yang deficiency is the very essence of kidney qi deficiency. Therefore, if the essence of the kidney is insufficient, the deficiency may affect the kidney yang and become kidney yang deficiency. In addition, essence and blood can feed each other, kidney essence deficiency is blood deficiency, essence and blood deficiency can also lead to kidney yin deficiency, kidney yin deficiency can cause yang hyperactivity, cause fire, a deficiency of heat evidence. The deficiency of kidney essence alone will not lead to deficiency heat or deficiency cold, but only to deficiency of both essence and qi, but further development of kidney essence deficiency will eventually lead to kidney yin deficiency or kidney yang deficiency or both kidney yin and yang deficiency.