1. The Five Elements The theory of the Five Elements is the essence of traditional Chinese culture, referring to the five fundamental substances: Wood (growth, flexibility, and smoothness), Fire (warmth, ascension, brightness), Earth (transformation, support, acceptance), Metal (purity, cleanliness, and contraction), and Water (coolness, nourishment, and downward movement). Ancient Chinese people recognized that these five elements are essential and that all things in the world arise from the interactions and transformations among them. There exists a relationship of mutual generation and restriction among these elements, maintaining a dynamic balance through their continuous interactions, which is the fundamental meaning of the Five Elements theory.
2. The Generative and Restrictive Relationships of the Five Elements: The Five Elements theory posits that there are generative (sheng) and restrictive (ke) relationships among the elements. The generative relationships explain the interconnections between things, while the restrictive relationships indicate the mutual influences when balance is disrupted. Generative relationships mean mutual support and growth. The order of generation is: Wood generates Fire, Fire generates Earth, Earth generates Metal, Metal generates Water, and Water generates Wood. Restrictive relationships mean mutual restraint and limitation. The order of restriction is: Wood restrains Earth, Earth restrains Water, Water restrains Fire, Fire restrains Metal, and Metal restrains Wood. The concepts of generation and restriction are inseparable; without generation, things cannot arise and grow; without restriction, things cannot maintain normal coordination. Only by maintaining a dynamic balance of generation and restriction can things develop normally.
3. The Five Elements and the Five Organs: Traditional Chinese Medicine (TCM) views the human body as a complex unity centered around the five organs, which, along with the six bowels and meridians, form five major systems. This is part of the systems theory in TCM. Therefore, discussing TCM health preservation inevitably involves the internal connections and mutual nourishing relationships among the five organs. Wood → Fire → Earth → Metal → Water Liver → Heart → Spleen → Lung → Kidney For example, Wood generates Fire, meaning the Liver (Mu) nourishes the Heart (Xin); the Liver stores blood, and the Heart governs blood vessels. A normal blood-storing function of the Liver supports the Heart’s function. Fire generates Earth, meaning the Heart (Xin) warms the Spleen (Pi); the Heart governs blood vessels and spirit, while the Spleen governs transformation and blood production. A normal function of the Heart ensures blood can nourish the Spleen, allowing it to perform its functions of transformation and blood production. Earth generates Metal, meaning the Spleen (Pi) supports the Lung (Fei); the Spleen can benefit Qi, transform Qi and blood, and transport essence to nourish the Lung, promoting its function of governing Qi. Metal generates Water, meaning the Lung (Fei) nourishes the Kidney (Shen); the Lung governs cleansing, and the Kidney stores essence. The Lung’s Qi descending helps the Kidney store essence and govern water. Water generates Wood, meaning the Kidney (Shen) nourishes the Liver (Mu); the Kidney stores essence, and the Liver stores blood. The essence from the Kidney can transform into blood for the normal function of the Liver. This mutual nourishing relationship among the five organs is explained using the generative theory of the Five Elements. The restrictive relationships among the five organs can be explained using the restrictive theory of the Five Elements: For example, the Heart belongs to Fire, and the Kidney belongs to Water; Water restrains Fire, meaning Kidney water can restrain Heart fire, preventing excessive Heart fire. The Lung belongs to Metal, and the Heart belongs to Fire; Fire restrains Metal, meaning Heart fire can restrain Lung Metal, as excessive Heart fire can inhibit the Lung’s cleansing function. The Liver belongs to Wood, and the Lung belongs to Metal; Metal restrains Wood, meaning Lung Metal can restrain Liver Wood, as excessive Lung Qi can inhibit Liver Yang’s hyperactivity. The Spleen belongs to Earth, and the Liver belongs to Wood; Wood restrains Earth, meaning Liver Wood can restrain Spleen Earth. If Liver Qi is smooth, it can relieve Spleen Qi stagnation. The Kidney belongs to Water, and the Spleen belongs to Earth; Earth restrains Water, meaning Spleen Earth can restrain Kidney Water, as the Spleen’s transformation can prevent Kidney Water from overflowing. This mutual restraint among the five organs is explained using the restrictive theory of the Five Elements.
4. The Five Tastes and the Five Organs: 1. Sour nourishes the Liver: Sour foods enhance digestive function and protect the liver. Regular consumption can aid digestion, eliminate harmful bacteria in the gastrointestinal tract, and prevent colds, lower blood pressure, and soften blood vessels. Foods primarily sour, such as sour plums, pomegranates, tomatoes, hawthorn, and oranges, are rich in vitamin C, which can prevent cancer, combat aging, and treat arteriosclerosis. 2. Bitter nourishes the Heart: There is an ancient saying that bitter medicine is good for health. TCM believes that bitter foods can drain, dry, and strengthen Yin, having effects of eliminating dampness and promoting diuresis. Foods like tangerine peel, bitter almonds, bitter melon, and lily can prevent toxin accumulation and treat various sores. 3. Sweet enters the Spleen: Sweet foods can nourish Qi and blood, replenish energy, relieve fatigue, and detoxify the stomach, also having effects of relieving spasms. Foods like brown sugar, longan meat, honey, and grain products are good choices for sweet foods. 4. Spicy enters the Lung: TCM believes that spicy foods can induce sweating and regulate Qi. Commonly consumed foods like scallions, ginger, garlic, chili, and pepper are primarily spicy; these foods can protect blood vessels and regulate Qi and blood, promoting meridian smoothness. Regular consumption can prevent colds, but those with hemorrhoids, constipation, or weak Kidney Qi should avoid them. 5. Salty enters the Kidney: Salty is the crown of the five tastes, and it is never tiresome. TCM believes that salty foods can regulate cell and blood osmotic pressure, maintaining normal metabolism. Salty foods have effects of draining, softening hardness, dispersing masses, and nourishing Yin blood. Foods like salt, kelp, seaweed, and jellyfish are high-quality salty foods. If the Kidney is too weak, Kidney water can prevent Heart fire from functioning properly. This is also a dangerous signal. We should be cautious about changes in the color of the glabella in daily life.
5. The Five Colors, Grains, and the Five Organs: 1. The Liver corresponds to the color green: It is advisable to eat brown rice, beef, jujube, and sunflower seeds; green corresponds to the Liver, so to achieve a rosy complexion, one should not primarily consume vegetarian food. 2. The Heart corresponds to the color red: It is advisable to eat adzuki beans, dog meat, plums, and leeks; red corresponds to the Heart, so to achieve a complexion like peach blossoms, one can supplement with foods rich in vitamin C, such as tomatoes, oranges, and red apples. 3. The Lung corresponds to the color white: It is advisable to eat wheat, lamb, apricots, and leeks; white corresponds to the Lung, so to achieve fair skin, one can regularly consume protein-rich foods like soy milk and milk. 4. The Spleen corresponds to the color yellow: It is advisable to eat soybeans and chestnuts; yellow corresponds to the Spleen, so those with a dull complexion can supplement with yellow, sweet foods like carrots and egg yolks. 5. The Kidney corresponds to the color black: It is advisable to eat meat, peaches, and scallions; black corresponds to the Kidney, so those with darker skin should eat less food with excessive color additives. 6. The Five Senses and the Five Organs: 1. The nose corresponds to the Lung: The shape of the nose is governed by the stomach Qi, and the nostrils are governed by the Lung Qi, so the Lung opens to the nose. If the Lung is diseased, it will first manifest in the nose. Here, the nose refers mainly to the nostrils; if the Lung is hot, the nostrils will exhale hot air; if the Lung is cold, the nostrils will exhale cool air. For example, when a person has a lung disease, symptoms like wheezing and flaring nostrils may appear. 2. The eyes correspond to the Liver: The Liver opens to the eyes, and liver disease will manifest in the eyes, generally causing the corners of the eyes to appear bluish. If a child is frightened, blue veins or bruises may appear on the bridge of the nose, which is also related to the Liver. In TCM’s correspondence of colors and organs, the Liver corresponds to the color blue. This blue is not the green of grass or leaves but a grayish color. The Liver is generated from Kidney water, and this gray color is a transition between black and blue. It is worth mentioning that if a person does not take care of their body in winter, they may become ill in spring when the Qi begins to rise. Therefore, understanding the correspondence between colors and organs is beneficial for health preservation; we can often judge the state of our body by observing changes in complexion. 3. The lips correspond to the Spleen: The Spleen opens to the mouth, and the lips are the Spleen’s organ. Those with Spleen disease may exhibit yellow lips or yellowing around the lips, chapped lips, or bleeding, all caused by excessive Yangming dryness and heat. 4. The tongue corresponds to the Heart: The tongue is the organ of the Heart. Heart disease generally manifests as an inflexible tongue or a curled tongue. Frequent verbal errors may also indicate insufficient Heart Qi. The Huangdi Neijing states: “Those with heart disease have a curled tongue and red cheeks.” Red cheeks indicate heart disease, and the cheekbones may appear red. In daily life, we should also pay attention to the glabella, as heart disease can also manifest there. If the glabella suddenly turns red and has a pattern resembling a flower, it indicates that the spirit is scattering, and we should be especially cautious, as this may signal a sudden severe illness. A dark glabella is also not a good sign; from a TCM perspective, this indicates excessive water Qi affecting the heart, meaning Kidney water is too abundant, restraining Heart fire. 5. The ears correspond to the Kidney: The ears are the organ of the Kidney. Ear diseases are related to the Kidney. The Huangdi Neijing states, “The Kidney opens to the ears.” Those with Kidney disease may experience symptoms like deafness or tinnitus. The five senses are closely related to the five organs; by understanding the changes in the five senses, we can discover hidden diseases in the five organs. Therefore, we must always pay attention to changes in the five senses to be aware of the corresponding conditions of the five organs. Specific methods for health preservation related to the five senses are simple: often close your eyes to nourish the spirit; speak less to nourish the heart; breathe steadily to nourish the lungs; eat delicious food to nourish the mouth; avoid unnecessary distractions and listen only to what is appropriate to nourish the ears.
7. The Five Emotions and the Five Organs: 1. “The Heart corresponds to joy” refers to the physiological function of the heart and its relationship with the emotion of joy. The Suwen: On Pain states: “Joy harmonizes Qi and allows the spirit to flow freely.” The process of joy is akin to the release of energy (both mental and physical) in the body, and the released energy forms the original driving force, initiating new mental activities and governing bodily vitality, creating new achievements. For example, it can enhance the vitality of the brain and the entire nervous system, fully unleash the body’s potential, improve the efficiency and endurance of both mental and physical labor, making life and work feel enjoyable and confident, resulting in agile, accurate, and energetic movements; it can strengthen the muscles of the heart and blood vessels, accelerate blood circulation, and enhance metabolic levels; it can expand the lungs, strengthen respiratory movements, increase lung capacity, and facilitate the exchange of carbon dioxide and oxygen; it can enhance the movement of digestive organs, increase the secretion of digestive fluids, thereby improving appetite, aiding digestion, and promoting metabolism.
2. “The Liver corresponds to anger”: Anger is a strong emotional response to external stimuli and is a negative emotional stimulus. Anger is most closely related to the Liver, hence the phrase “The Liver corresponds to anger.” On one hand, excessive anger can harm the Liver, leading to abnormal Qi flow, excessive Liver Qi, and blood surging with Qi, which can manifest as a flushed face, red eyes, irritability, and in severe cases, can lead to vomiting blood, nosebleeds, sudden fainting, or loss of consciousness. On the other hand, if the Liver fails to regulate, it can also lead to emotional instability, manifesting as irritability and restlessness. 3. “The Spleen corresponds to thought”: Thought refers to the state of conscious mental activity. The emotional activities of thought are primarily expressed through the Spleen. Thought is a state of highly concentrated mental activity. When a person is immersed in thought or anxiety, they often experience a lack of appetite and food may seem tasteless. Some women may experience reduced menstrual flow or irregular periods due to work stress and intense concentration, which aligns with the Spleen’s function of governing blood. 4. “The Lung corresponds to worry (sadness)”: Ancient physicians observed that the Lung is the main organ expressing worry and sadness. When a person cries due to worry, tears flow, which is mucus secreted by the Lung. When crying, Lung Qi is abundant, and mucus secretion increases, and since the Lung opens to the nose, tears flow from the nose. The Lung governs Qi and is the master of sound; thus, worry and sadness can lead to hoarseness and rapid breathing. The Lung also governs the skin, so worry can increase facial wrinkles. 5. “The Kidney corresponds to fear”: Fear is related to the Kidney, which is the main organ expressing fear. Fear is a mental state of apprehension towards things, which is a negative stimulus to physiological activities. The Suwen: On Pain states: “Fear causes Qi to descend, and shock causes Qi to become chaotic.” This indicates that the stimulus of fear can adversely affect the body’s Qi flow. “Fear causes Qi to descend” means that in a state of fear, the Qi in the upper body becomes blocked, leading to fullness in the lower body, and in severe cases, can cause incontinence. “Shock causes Qi to become chaotic” means that normal physiological activities can be temporarily disrupted due to panic, resulting in confusion and indecision.
8. The Five Seasons and the Five Organs: 1. Spring is suitable for ascending and nourishing: In spring, Yang Qi begins to arise, the earth revives, and all things grow upwards, corresponding to the Liver. Based on the characteristics of spring, we should use ascending and dispersing products like mulberry leaves, chrysanthemum, and ginger to fully mobilize the body’s Yang Qi, harmonizing Qi and blood. 2. Summer is suitable for cooling and nourishing: Summer is hot, with excessive fire evil, and all things flourish, corresponding to the Heart. Based on the summer season, the body’s organs and Qi are abundant, and we should use light and cooling products like honeysuckle, lotus leaves, and lotus seeds to regulate the body’s Yin and Yang Qi. 3. Late summer is suitable for light nourishment: Late summer is the transition between summer and autumn, with heat descending and humidity rising, corresponding to the Spleen. We should use light and draining products like adzuki beans, mung beans, and patchouli to benefit the Spleen and achieve a source of Qi and blood generation. 4. Autumn is suitable for cooling nourishment: In autumn, Yang Qi retracts, and Yin Qi grows, with dry weather, corresponding to the Lung. At this time, the five organs have just recovered from the vigorous metabolism of summer, and we should use products like lily and black sesame to nourish Yin and generate fluids, regulating the dysfunction of the organs from summer. 5. Winter is suitable for warming nourishment: In winter, the weather is cold, and Yang Qi is deeply hidden, corresponding to the Kidney. We should use warming products like longan, walnuts, and donkey-hide gelatin to nourish the body’s Qi and blood deficiency, ensuring the organs’ Qi and blood are abundant and adapting to changes in the natural environment.
9. The Five Fluids and the Five Organs: Sweat, mucus, tears, saliva, and spittle are referred to as the Five Fluids. The Five Fluids are generated by the Five Organs: the Heart produces sweat, the Lung produces mucus, the Liver produces tears, the Spleen produces saliva, and the Kidney produces spittle. The Five Fluids are categorized under body fluids, all generated from body fluids, distributed among the organs, playing roles in nourishing, moistening, and regulating fluid metabolism. The generation, distribution, and excretion of the Five Fluids occur during the process of body fluid metabolism, resulting from the combined actions of multiple organs, particularly the Lung, Spleen, and Kidney. However, the Five Organs are the core of the organ representation theory, thus the sweat, mucus, tears, saliva, and spittle are attributed to the Five Organs. Therefore, it is said: “In a person’s body, there are mucus, tears, saliva, spittle, urine, and feces, all belong to the transformation of one water, and are emitted through the nine orifices” (from Questions and Answers). “Sweat and urine can both be called body fluids” (from Notes on Medicine). The relationship between the Five Organs and the Five Fluids is a unity of overall regulation and local regulation during the metabolism of body fluids.
1. Sweat is the fluid of the Heart: What is sweat? “Yang added to Yin is called sweat” (from Suwen: On Yin and Yang). “Yang” refers to the Yang Qi in the body; “Yin” refers to the Yin fluids in the body. The phrase “Yang added to Yin is called sweat” means that sweat is the body fluid transformed from body fluids through Yang Qi’s evaporation and is expelled from the skin (sweat pores). The secretion and excretion of sweat also rely on the opening and closing of the defensive Qi on the skin. When the pores are open, sweat is excreted; when the pores are closed, there is no sweat. Since sweat is transformed from body fluids, and blood and body fluids originate from the same source, there is a saying that “sweat and blood share the same source.” Blood is governed by the Heart, and sweat is the fluid of the Heart, transformed from Qi, hence it is called “sweat is the fluid of the Heart.” As Li Zhongzi said: “What the Heart stores internally is blood, and what is emitted externally is sweat; thus, sweat is the fluid of the Heart” (from Essential Readings in Medicine).
Due to the close physiological relationship between sweat and blood, they also influence each other pathologically. In terms of the relationship between sweat and blood, excessive sweating can deplete blood and damage body fluids. Conversely, insufficient body fluids can lead to low blood volume, resulting in insufficient sweat. Therefore, in clinical practice, when blood deficiency symptoms appear, one should be cautious in using sweating methods. The principle of “depleting blood leads to no sweat, and depleting sweat leads to no blood” is based on this. Regarding the relationship between sweat and the Heart, excessive sweating can deplete the Heart’s Qi and blood, leading to symptoms like palpitations and anxiety. Since sweating is the result of the evaporation of body fluids due to Yang Qi, excessive sweating can also harm the body’s Yang Qi, leading to a critical condition of excessive sweating depleting Yang. Conversely, when the Heart’s Qi and blood are insufficient, it can also cause pathological sweating, such as in cases of Heart Qi deficiency, where the defensive Qi is not solid, leading to spontaneous sweating; or in cases of Heart Yin deficiency, where Yang does not restrain Yin, leading to night sweats.
2. Mucus is the fluid of the Lung: Mucus is the viscous secretion from the nose, which serves to moisten the nasal passages. The nose corresponds to the Lung, and the Five Organs generate fluids, with the Lung producing mucus. When the Lung’s physiological function is normal, mucus moistens the nasal passages without flowing out. If the Lung is affected by wind-cold, clear mucus may flow from the nose; if affected by wind-heat, turbid mucus may flow; if the Lung is dry, there may be little or no mucus.
3. Saliva is the fluid of the Spleen: Saliva is the mouth’s fluid, with the clearer part referred to as saliva. Saliva protects and cleanses the mouth. During eating, saliva is secreted in larger amounts, moistening and dissolving food, making it easier to swallow and digest. Under normal circumstances, saliva rises in the mouth but does not overflow. If the Spleen and Stomach are not harmonious, it often leads to excessive saliva secretion, resulting in drooling, hence it is said that the Spleen generates saliva.
4. Tears are the fluid of the Liver: The Liver opens to the eyes, and tears flow from the eyes. Tears serve to moisten and protect the eyes. Under normal circumstances, tear secretion is moistening and does not overflow, but when foreign objects invade the eyes, tears can be secreted in large amounts to cleanse the eyes and expel the foreign objects. In pathological conditions, abnormal tear secretion may occur. For example, insufficient Liver Yin blood can lead to reduced tear secretion, often resulting in dry eyes; if there is wind-heat in the Liver channel, there may be increased tears and weeping in the wind. Additionally, in cases of extreme sadness, tear secretion can also increase significantly.
5. Spittle is the fluid of the Kidney: Spittle and saliva are both oral fluids, with the thicker part referred to as spittle and the thinner part as saliva. The Spleen’s fluid is saliva, while the Kidney’s fluid is spittle. In addition to moistening and dissolving food, making it easier to swallow, and cleansing and protecting the mouth, spittle also nourishes Kidney essence; since spittle is transformed from Kidney essence, excessive spittle or prolonged spitting can deplete Kidney essence, which is why practitioners often swallow spittle to nourish Kidney essence.
The Five Elements, Five Organs, Five Tastes, Five Colors, Five Senses, Five Emotions, Five Seasons, and Five Fluids are all interrelated and inseparable. As long as you grasp their interrelationships and apply them to daily health preservation, you will surely achieve a healthy body!