According to Traditional Chinese Medicine, the kidneys are the fountain of youth, the foundation for a healthy, vital life and for graceful longevity. They are to be guarded and nurtured by living wisely, so that they in turn may continue to supply us with strength well into old age.
From Western anatomy and physiology, we know that the kidneys perform several critical functions in the body: waste removal and filtration, regulation of the acidity of the blood, maintenance of optimum levels of electrolytes and amino acids, and regulation of blood pressure. The kidneys also secrete hormones. Among them are erythropoetin, which stimulates red blood cell production in the bone marrow so that we do not become anemic; and calcitriol, an active form of vitamin D, which is now recognized as essential to a myriad of body functions such as immune and cognitive function, healthy fertility, weight regulation, and of course, bone health.
As we consider all of these functions, and ponder the wide-ranging effects that they have on the entire organism, or conversely, the negative effects of a malfunctioning kidney system, we can begin to appreciate the respect that TCM accords this vital organ system.
TCM was, of course, a prescientific medicine without knowledge of hormones, amino acids, enzymes, and the like, and so it described kidney function in different terms. In TCM, the kidney is the foundation for growth, development, and reproduction; for healthy bones and marrow; and for brain functions such as memory, concentration, and intelligence. The kidney regulates fluid metabolism; supports keen hearing, healthy hair, and strong sexual function; and supplies us with willpower and motivation. Between the two kidneys, at the small of the back, resides the ultimate life force known as the “The Gate of Vitality.” 16th Century TCM doctor, Zhang Jie Bin, describes it thus: “The Gate of Vitality is the residence of Yin and Yang, the Sea of Essence, and it determines Life and Death.”
Kidney essence refers to our genetic inheritance – the constitution and resistance to illness that we inherit, which determines to a large degree how healthy and strong we will be. In traditional Chinese culture, guarding and cultivating one’s kidney essence was elevated to an art, reflected in innumerable martial arts exercises, herbal recipes, and prescriptions for healthy living. Today, Chinatown restaurants routinely serve kidney congee – rice porridge with kidneys – to old people who are diligently applying the principle of “like for like.”
This repertory of methods for the strengthening of our kidneys can hold us in good stead as we face the many challenges of modern living and attempt to travel into old age with our bodies and faculties intact.
FERTILITY AND SEXUALITY
Fertility and healthy sexuality depend on a rich supply of blood and essence to the reproductive organs, on the one hand, and a sufficiently hot “fire” on the other. For the blood aspect, TCM uses kidney yin tonics: nourishing, moistening herbs that provide luxuriant tonification and can improve the uterine lining, maintain the quality of eggs and sperm, and enhance vaginal lubrication. The prime example of such a substance is wine-steamed Rhemannia root, Shu Di Huang. The very look of the sliced root speaks to its effects: black, glistening, heavy, and pliable, so unlike most other roots, which tend to be dry and woody – a true ambrosia.
Other essence-nourishing herbs include sour, red fruits such as cornelian cherry Shan Zhu Yu or schisandra berry Wu Wei Zi. The sourness tones the mucus membranes and encourages production of fluids. The red colour usually indicates the presence of plant chemicals which benefit and nourish the blood.
In order to boost the fire, we must enhance the Yang aspect of the kidneys, which will translate into increased sexual desire, better motility of sperm, and a healthy luteal phase of the menstrual cycle. Herbs such as Epimedium Yin Yang Huo (also known as horny goat weed), Morinda Ba Ji Tian, and Eucommia Du Zhong provide the spark.
MIND AND SPIRIT
Poor memory, insomnia, listlessness, and lack of clarity and motivation can all indicate low or declining kidney function. These symptoms often appear at menopause, when the kidney energy has begun its natural decline. This begins to happen subtly in the early 40s, as many of us are finding out, and kicks into high gear once menstruation stops. The end of the menstrual period is a reflection of waning essence, but mind and spirit symptoms can be kept at bay with kidney tonics that specifically nourish the brain. Formulas such as the gorgeously-named Sagacious Confucius Pillow Elixir will sharpen the mind and calm the nerves, as well as provide control of concurrent symptoms like sweating, by using heavy and mineral rich substances such as turtle shell Gui Ban and fossilized bone Long Gu, to “ground” the spirit/mind.
SKIN AND HAIR
Patients will often remark that their skin is soft and smooth after taking blood and kidney tonics, and one of the prime substances responsible for this is prepared fleeceflower root He Shou Wu. This medicinal nourishes the skin and nails, prevents graying of hair, and combined with Goji and Rhemannia, will moisten the skin from the inside. Externally, pearl powder creams have traditionally been used to beautify the skin and remove blemishes.
WEIGHT AND FLUID BALANCE
It is a sad fact for many middle-aged people that weight gain is suddenly too easy, and not necessarily in proportion to the number of calories ingested. The middle age spread advances in spite of salads, protein shakes, and yoga, and one piece of cake will seemingly cause you to gain a full waist size. Again, you can blame the waning kidney fire, especially if you’ve doused it with a lifetime of hard living, bad food, and stress. This condition corresponds closely to the adrenal fatigue and insulin resistance of naturopathic fame, and while the treatment is often complex and multifaceted, some measure of kidney and spleen tonics always play a part in re-igniting the fluid and food transformation that will keep the weight down.
Astragalus root Huang Qi is primary here. While it is not traditionally a kidney tonic, it is used in modern times to treat many kidney diseases, and to regulate weight and fluid balance in the body. By turning up the heat a little on the digestive and kidney fires, it can make the metabolism more efficient. For this purpose, it is combined with many other categories of herbs, such as diuretics, digestives, and liver support herbs.
Maintaining a balanced lifestyle with healthy food, plenty of sleep, and low stress will preserve your kidney essence. On the other hand, excessive work, excessive exercise, sex, drugs, alcohol, excessive caffeine, anxiety, and stress will deplete kidney essence before its time.
Winter is the season of the kidney, a time when the body naturally seeks warmth and nourishment, and when the richness of kidney tonic herbs are least likely to cause side effects such as heat-congestion and phlegm in the body, as they might easily do in summer. Taking a course of kidney tonic herbs each winter can offer a wonderful preventive regimen that keeps the essence topped up for another year.