According to Traditional Chinese Medicine (TCM) theory, meridians refer to the general term for the channels (jingmai) and collaterals (luomai). The term “jing” implies a pathway, as the main channels connect the upper and lower parts of the body, linking the internal and external systems. The term “luo” implies a network, as the collaterals are branches that diverge from the main channels, smaller in size, crisscrossing and spreading throughout the body. The
“Lingshu: Pulse Measurement” states: “The main channels are internal, while the branches that spread horizontally are the collaterals; the branches of the collaterals are called ‘sun’.”
The meridians internally connect to the organs and externally link to the limbs and joints, facilitating communication between the internal organs and the body surface, thus forming an organic whole. This system allows for the circulation of Qi and blood, nourishing Yin and Yang, maintaining the functional activities of various parts of the body in a coordinated and relatively balanced manner.
In clinical acupuncture treatment, the differentiation of syndromes, selection of acupoints along the meridians, and techniques of tonifying or dispersing are all based on meridian theory. Therefore, the
“Lingshu: Meridian Differentiation” states: “The twelve main channels are the basis of life, the cause of disease, the means of treatment, and the origin of learning and practice.”
This highlights the significant importance of meridians in physiology, pathology, diagnosis, and treatment, which has been emphasized by physicians throughout history.
The meridian system is largely named according to Yin and Yang. All things can be divided into Yin and Yang, which are interrelated. The naming of meridians embodies this concept. One Yin and one Yang evolve into three Yin and three Yang, which have corresponding relationships (interior and exterior correspond).
The three Yin and three Yang are categorized based on the abundance (quantity) of Qi:
The most abundant Yin Qi is Taiyin, followed by Shaoyin, and then Jueyin; the most abundant Yang Qi is Yangming, followed by Taiyang, and then Shaoyang. The
“Suwen: Great Discussion on the True Essentials” asks: “What are the three aspects of Yin and Yang?” “It refers to the differences in the quantity and function of Qi.” “What is Yangming?” “It is the convergence of two Yangs.” “What is Jueyin?” “It is the complete intersection of two Yins.”
The names of the three Yin and three Yang are widely applied in the naming of meridians, including main channels, collateral channels, and sinew channels. The three Yin of the hand (Taiyin, Shaoyin, Jueyin) are located on the inner side, while the three Yang of the hand (Yangming, Taiyang, Shaoyang) are on the outer side; the three Yang of the foot (Yangming, Taiyang, Shaoyang) are on the outer side, while the three Yin of the foot (Taiyin, Shaoyin, Jueyin) are on the inner side. The naming of the Yin and Yang of the hands and feet indicates the close relationship between the formation of meridian theory and the limbs.
In the silk manuscripts unearthed from the Mawangdui Han tomb, there are two versions regarding the eleven meridians (the second version is further divided into two sub-versions, with similar text), which are earlier than the Neijing in ancient meridian theory literature. The names of the eleven meridians are based on the division of Yin and Yang between the “arms” and “feet,” consistent with the significance of the Yin and Yang division of the hands and feet.
In summary, when utilizing meridians for health maintenance, it is essential to distinguish the Yin and Yang of the meridians themselves to effectively and scientifically utilize them.
Understanding the “Network” Map of Your Body
Meridians consist of main channels and collaterals; the main channels are the primary pathways, while the collaterals are the branches. The human body has 12 main channels, also known as the “Twelve Regular Meridians,” along with countless collaterals. The main channels and collaterals crisscross, forming a vast network within the body. This network connects the internal organs and limbs, encompassing all parts of the body, including organs, muscles, skin, and hair. Let us explore this “network” within our bodies.
1. Main Channels — Beware of Early Flooding Disasters
The main channels are the core of the meridian system, divided into regular channels and extraordinary channels. There are 12 regular channels and 8 extraordinary channels. If the twelve regular channels are likened to rivers flowing continuously, the eight extraordinary channels resemble a reservoir. Normally, the Qi and blood flow through the twelve regular channels, while the eight channels operate quietly; however, when the Qi and blood in the twelve regular channels are insufficient and sluggish, the water from the reservoir of the eight extraordinary channels will supplement the rivers. If the flow becomes excessive and turbulent, the reservoir will increase its storage, allowing the Qi and blood to flow smoothly, thus maintaining the balance of normal bodily functions.
(1) Twelve Main Channels
The twelve regular channels consist of the three Yin channels and three Yang channels of the hands and feet, collectively known as the “Twelve Main Channels,” which are the core of the meridian system. They correspond to the twelve organs, with each channel named after its associated organ, following their pathways through the hands and feet, and various positions of the body, based on the theory of Yin and Yang, which assigns different names.
The names of the twelve main channels are: Hand Taiyin Lung Channel, Hand Jueyin Pericardium Channel, Hand Shaoyin Heart Channel, Hand Yangming Large Intestine Channel, Hand Shaoyang Sanjiao Channel, Hand Taiyang Small Intestine Channel, Foot Taiyin Spleen Channel, Foot Jueyin Liver Channel, Foot Shaoyin Kidney Channel, Foot Yangming Stomach Channel, Foot Shaoyang Gallbladder Channel, and Foot Taiyang Bladder Channel.
The twelve main channels are the primary pathways for the circulation of Qi and blood. Through the connections of the Yin and Yang of the hands and feet, they form a continuous, cyclical system of transmission, akin to a river flowing endlessly, allowing Qi and blood to reach the internal organs and surface of the body, nourishing the entire system.
The flow sequence is:
(2) Eight Extraordinary Channels
The eight extraordinary channels include the Ren Channel, Du Channel, Chong Channel, Dai Channel, Yin Qiao Channel, Yang Qiao Channel, Yin Wei Channel, and Yang Wei Channel. Unlike the twelve regular channels, they do not directly connect to the organs and do not have an interior-exterior relationship; their pathways are unique and thus referred to as extraordinary channels. Their function is to connect the twelve main channels, regulating the accumulation and distribution of Qi and blood among them.
(3) Twelve Channel Branches
The twelve channel branches are derived from the twelve main channels, primarily strengthening the connections between the two channels that correspond to each other. They reach certain organs and body parts that are not directly traversed by the main channels, thus compensating for the deficiencies of the main channels.
2. Collaterals — Beware of Blockages in Qi and Blood Transportation
Collaterals are branches of the main channels, which can be classified into branch collaterals, superficial collaterals, and sun collaterals, playing a role in the distribution of Qi and blood throughout the body.
(1) Fifteen Collaterals
The twelve main channels and the Ren and Du channels each have one collateral, plus the large collateral of the spleen, totaling 15 collaterals, known as the fifteen collaterals, named after the acupoints they originate from. They facilitate communication between the interior and exterior of the main channels, governing the superficial and sun collaterals, and nourishing the entire body with Qi and blood.
(2) Sun Collaterals
The smallest branches that diverge from the branch collaterals are called “sun collaterals,” which function similarly to superficial collaterals in distributing Qi and blood to nourish the entire body.
(3) Superficial Collaterals
Among all the collaterals, those that run superficially are called “superficial collaterals,” which are distributed on the surface of the skin. Their primary function is to distribute Qi and blood to nourish the entire body.
Through this analysis, the operation of the human meridian system resembles a city traffic map, clear and straightforward, making the concept of meridians less complex.
Meridians are the Pathways for Qi and Blood Circulation in the Body
Thus, the root of disease lies in the meridians. In other words, the key to life, survival, illness, and treatment all revolves around the meridians. The Huangdi Neijing highly praises the role of meridians in the human body, stating that meridians are “the basis of life, the cause of disease, and the means to treat all ailments.” Specifically, they have the following functions:
Meridians are the general term for the channels and collaterals. Some say that meridians are the routes for Qi and blood circulation, distributed throughout the body.
If our body is likened to a skyscraper, then the meridians are like the electrical wiring hidden within the walls of the building. The illumination of the building depends entirely on these networks, and if the wiring malfunctions, the building will be plunged into darkness. The human body is similar; if the meridians are obstructed, Qi and blood cannot be smoothly transported to various organs, leading to health issues.
The existence of life depends on the meridians: diseases occur due to problems with meridian activity. The Huangdi Neijing states that meridians can control all bodily functions, determining life and death, and treating various diseases; the treatment of diseases is also due to the action of the meridians.
Meridians function as a vast network system within the human body, and when they are unobstructed, they can dispel diseases and strengthen the body, promoting health and longevity. The term “unblocking the meridians” refers to ensuring that the Qi within the meridians flows freely; if the meridians are obstructed, Qi and blood will be imbalanced, leading to various diseases. Below, we will elaborate on several aspects:
1. “Determining Life and Death, Treating All Diseases”
The normal functioning of the meridians determines life and death. The
“Lingshu: Sea Discussion” states: “The twelve main channels are internally connected to the organs and externally linked to the limbs.” The
“Lingshu: Internal Organs” states: “The meridians are responsible for the circulation of Qi and blood, nourishing Yin and Yang, moistening the tendons and bones, and facilitating the joints.”
These clearly illustrate the significant role of meridians in human life activities. The reason humans can function as an organic whole is due to the interconnection of the meridians, which link the interior and exterior, connecting the upper and lower parts, internally linking the five organs and six bowels, and externally reaching the skin and muscles. Without this communication and connection provided by the meridians, how could the various tissues and organs of the body be nourished? The circulation of Qi and blood is crucial for the organs to communicate, allowing Yin and Yang to interact, and the internal and external systems to connect. If Qi and blood do not circulate, the connections between the organs will be obstructed, leading to disease, and in severe cases, even death.
The great physician Yu Jiayan said: “In treating diseases, one must understand the organs and meridians; otherwise, one will make mistakes as soon as they open their mouths or take action.” The
“Lingshu: Nine Needles and Twelve Origins” states: “Unblock the meridians and regulate the Qi and blood.”
The treatment of diseases and the recovery of the body must start from the meridians. It is well known that pain is one of the most common symptoms of illness. According to TCM, it is said that “where there is flow, there is no pain; where there is pain, there is no flow.” Only when the meridians are unobstructed can Qi and blood circulate; only with the circulation of Qi and blood can patients receive treatment and recovery.
2. Connecting the Organs and Communicating the Whole Body
Meridians can connect all parts of the body, including the internal organs, limbs, five senses, skin, muscles, tendons, and bones, just as underground cables connect an entire city. When the pathways are clear, the body can maintain balance and unity, sustaining normal activities.
3. Regulating Deficiency and Excess, Circulating Qi and Blood
According to TCM theory, the Qi and blood of the internal organs are the same as those of the meridians. If there are issues with the internal organs, stimulating the meridians and acupoints on the body surface can adjust the deficiency and excess of Qi and blood. For example, in cases of gastric spasm, needling the Zusanli (ST36) acupoint can relax the stomach; for deficiency syndromes, tonifying methods are used, such as needling Zusanli (ST36) to strengthen contraction. Of course, due to the differences in deficiency and excess syndromes, although both use Zusanli (ST36), the techniques differ: one uses dispersing methods, while the other uses tonifying methods. This example illustrates that meridians have the function of adjusting deficiency and excess. The smooth flow of the meridians relies on movement. Because “movement leads to resolution of stagnation,” “movement prevents decline,” and “flowing water does not rot, and the door hinge does not decay.” Only through movement can Qi and blood circulate throughout the body; regular practice of Qigong can also unblock the meridians, as the “Zhoutian Circulation Method” and “Rising and Falling Opening and Closing Method” in Qigong are important techniques for ensuring the normal flow of Qi along the meridians. Additionally, regularly consuming herbs and foods that regulate Qi and invigorate blood, such as Chenpi (dried tangerine peel), Muxiang (saussurea), Sharen (cardamom), Simiao San (Four Milled Decoction), Yueju Wan (Yueju Pill), Danggui (Angelica), Chuanxiong (ligusticum), Taoren (peach kernel), Honghua (safflower), Youcai (rapeseed), and Heidazong (black soybean), is beneficial for unblocking the meridians. A cheerful mood also helps in keeping the meridians unobstructed, as “worry and anxiety cause Qi to stagnate and not flow.” Therefore, regardless of any unpleasant events, it is essential to maintain a positive mindset to prevent Qi and blood from becoming stagnant.
Natural gas needs to be transported through pipelines to various locations; similarly, Qi and blood must be delivered through the meridians to nourish the entire body, both internally and externally. This is the second function of the meridians. Every person’s life depends on Qi and blood for sustenance, and the meridians are the pathways for Qi and blood circulation. Only by utilizing the meridian system to transport Qi and blood and other nutrients throughout the body can one maintain normal physiological activities.
4. Defending Against Pathogenic Factors, Protecting the Body
External diseases often invade the body from the surface and gradually develop inward, starting from the skin. The meridians connect internally and externally with the skin, allowing Qi and blood to flow to the surface, forming a solid wall like bricks and tiles. Whenever external enemies invade, the meridians are the first line of defense, serving as a barrier to resist external pathogens and protect the body.
5. Reflecting the Internal State, Knowing the Inside from the Outside
Diseases can also arise from within; for example, “disease enters through the mouth” refers to illnesses caused by consuming unclean food, leading to abnormal Qi and blood within the body. This internal disease first manifests as abnormal Qi and blood in the internal organs, which is then reflected through the meridians at corresponding acupoints.
Thus, acupoints along the meridians can also reflect internal issues, a concept in TCM known as “knowing the inside from the outside.”
6. Stimulating the Meridians, Adjusting Qi and Blood
The human body has great potential; for instance, only 1/3 of the liver is actively working, and only 1/7 of the heart is functioning… If they encounter problems, the first step is to stimulate and mobilize the body’s potential. According to TCM theory, the Qi and blood of the internal organs are interconnected with those of the meridians. If there are issues with the internal organs, stimulating the meridians and acupoints on the body surface can adjust the deficiency and excess of Qi and blood. This is also the reason why acupuncture, massage, and Qigong can treat internal diseases.
The mouth not only serves to eat but can also introduce bacteria, becoming a pathway for disease infection. Similarly, the meridians can circulate Qi and blood and perform the aforementioned functions, but once the body is ill, they also become the route through which diseases “travel” from the outside in. By understanding their pathways, we can utilize this knowledge to prevent the progression of diseases. This is akin to knowing the enemy’s route of attack, allowing us to prepare defenses in advance.
Ancient Chinese medicine discovered the existence of meridians through long-term clinical practice. The ancients defined meridians from a practical perspective: meridians are the pathways for Qi and blood circulation in the body, internally connecting to the organs and externally distributed throughout the body, linking various tissues and organs into an organic whole.