"In order to bring into harmony the human body one takes as standard the laws of the four seasons and the five elements."
- The Yellow Emperor, Huang Ti Nei Jing Su Wen, approx. 200 B.C.
Health is more than the absence of disease, and well-being is more than the absence of symptoms. The Chinese concept of true health is a state of balance and harmony, both internally and with the world at large.
Chinese medicine is based on the laws of Nature, discovered after centuries of observation. These laws are reflected in the changes of the seasons. showing five distinct phases or movements of Nature.
These five phases (sometimes called elements) are Wood, Fire, Earth, Metal and Water, and are linked, respectively, to Spring, Summer, Later Summer, Fall, and Winter. All of Chinese medicine is grounded in this law of the five elements. Living in harmony with these five elements, then, was the way to health.
Wood is the name the Chinese gave to the energy of Spring. It is explosive, fast-moving and powerful, just like the growth of plants and trees in the Springtime. Although slow, inner transformations take place all winter inside the buds, roots, and seeds, in Spring this growth becomes rapid and outward. Since we are a part of Nature, we also experience this energy of Wood.The Wood energy in our bodies governs our growth and the structures that support our growth - specifically our trunk, limbs and joints. It also governs muscles, tendons and ligaments, so that the physical ability to be flexible and strong is governed by the healthiness of our Wood. Problems with muscle weakness or stiffness could point to an imbalance in Wood.
The organs associated with the Wood energy are the Liver and Gall Bladder; thus our digestion and overall metabolism and vitality are dependent on healthy Wood functioning. The classics say that the Liver nourishes the eyes, and thus our eyes and our vision are connected to Wood. In addition to physical vision, our capacity to visualize, to envision the future, and to have a vision for our lives has its origin here.
The energy of the Summertime is Fire. It is heat and light, the warmth of the sun and the long, light-filled days of summer. Fire is expansive and kinetic, a metaphor for the life-force itself. The growth that began so powerfully and rapidly in the Spring now reaches a peak of lush maturity, as all of Nature flowers and begins to bear fruit.
The Fire energy in our bodies governs our physical warmth and the circulation of blood through our blood vessels. The ability to maintain an even temperature and to be adequately warmed from within is governed by Fire. Problems with circulation, such as arteriosclerosis, varicose veins, and chronically cold hands and feet could point to an imbalance in the Fire energy.
The organs associated with the Fire element are the Heart and Small Intestine. The Heart is the pump which circulates our blood. It is also traditionally seen as the place in the body where we feel love and joy. The Small Intestine is seen as the Sorter of the Pure from the Impure. This process is alchemical, sorting physical substances into pure and impure in the digestive tract as well as sorting on the mental and emotional levels.
Earth is the name given to the energy of Late Summer. In the yearly cycle, it is the short, transitional season between Summer and Fall - the season of the harvest. This season is a time of intense metamorphosis in Nature, a time of fullness and ripeness, richness and abundance. This is Mother Nature at her most bountiful - the days are warm, the nights are cool, and there is plenty of good food to eat. If there's been a good harvest, we feel content and secure that we will be provided for in the Winter months ahead.
The Earth energy in our bodies governs our ability to nourish ourselves through the foods we eat, how we "harvest" our daily bread. It also governs all the cycles and rhythms of life - the menstrual cycle, our sleeping, eating and breathing cycles are all determined by the harmony of our Earth energy. Any disruption of a natural cycle, or any difficulty with eating or digestion could point to an imbalance in the Earth.
The organs associated with the Earth are the Stomach and Spleen/ Pancreas. They are essential for digestion and the nourishment of the whole body-mind-spirit. The Stomach in the classics is called "the official of the public granaries" - it receives the food you eat and must transform it into something which the body can use. The Spleen/Pancreas, in the Chinese model, is in charge of distributing the nourishment throughout the body.
Metal is the name given to the energy of Autumn. Like the mineral ores, salts and gems of the earth, Metal energy represents strength, structure and quality. The minerals of the soil provide the richness that nourishes living things, and the metallic ores provide the materials for structural strength and for conduits through which communications flow.
On the functional level, Metal is the energy of letting go, of losing all that is inessential. Like the trees as they shed their leaves, it is a paring down to the bare bones, so that you can see the inner structure of the naked branches. As the year slows down to prepare for Winter's rest, so we turn inward, pause and take stock of how far we've come in the year's growth.
The Metal energy in our bodies governs our basic rhythms of receiving and letting go through the breath and through our bodily eliminations. The rhythm of our breath also governs other cycles in the body, including the heart rhythm and the blood circulation. From this, it is not surprising that the organs associated with the Metal element are the Lungs and Large Intestine. Professor Worsley says the Lungs "receive the pure qi from the Heavens." Thus we receive air (qi) into our lungs, and also into every cell of our bodies. The Large Intestine, says the Nei Jing, are "like the officials who propagate the Right Way of Living, and they generate evolution and change." If our Large Intestine is not working properly, then our whole life process begins to slow down, becoming stagnant and stuck, so that change becomes impossible - we've lost the rhythm of taking in and letting go which allows for change.
Water is the name given to the energy of Winter. It is wet and cold, sinking and receptive, (like the depths of the ocean or the still darkness of a winter's night). After the harvesting and letting go of the Fall, all things go inside in Winter, or die down to their roots. It is a time of seeming non-activity, of quiescence, when ground water is stored up in the earth to nourish the new growth the following Spring.
The Water energy in our bodies governs all of our fluid systems - it is the medium for our blood and lymph circulation, our tears, sweat, saliva, urine, and sexual secretions. Because our bodies are about 78% water, the harmonious movement of this energy is very important for health. Problems with dryness, or swelling and edema, could point to an imbalance in Water energy.
It is no surprise that the organs associated with Water energy are the Kidneys and the Urinary Bladder. The Urinary Bladder's job is to "store the overflow," according to the Nei Jing. The Kidneys' role is to move the fluids around in our bodies so that we have lubrication and fluidity where we need it - as the classics say, "the kidneys are like the officials who do energetic work."
The Kidneys are also perceived as storing the Vital Essence, or Jing - the internal reservoir of the life force itself.