Chinese Medicine Demystified (Part 5): Acupuncture Over Drugs
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Chinese Medicine Demystified (Part VI): 5 Ways Acupuncture Can Help You Where Drugs and Surgery Can’t

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Note: This is the sixth article in an ongoing series. If you haven’t read the first five, I recommend doing that before continuing:

Most people in the US don’t know much about acupuncture. They might have heard it’s good for pain, that it can treat infertility, or that it can help you relax. What most people don’t realize is that acupuncture is a more complete and effective method of healthcare than western medicine.

Here’s why.

#1: Acupuncture treats your whole body

Acupuncture isn’t directed toward a particular disease or condition. It works instead by activating the body’s self-healing ability. This is why acupuncture can address everything from irritable bowel syndrome to back pain to the side effects of chemotherapy.

When you get an acupuncture treatment for elbow pain, your elbow pain will go away but it’s also likely that you’ll see improvements in other areas. The headaches you’ve had for ten years will get better, you’ll have more energy, you’ll be better able to handle stress, and you’ll sleep better.

The reason acupuncture can do this is that it focuses on treating the root cause of your health problems. The ancient Chinese knew that symptoms don’t arise out of nowhere. Symptoms are manifestations of an underlying malfunction and disease process.

The progression from malfunction > disease process > symptom can take many years. If you just address the symptom without addressing the malfunction or disease process, healing doesn’t occur.

The Chinese also knew that a malfunction or disease process can give rise to many different symptoms that may seem unrelated. For example, headaches, heartburn and skin rashes may all be expressions of the same underlying problem.

Western medicine, on the other hand, often mistakes symptoms for disease. Treatment is almost always directed at the symptom, not the disease. Western medicine is based on the Cartesian paradigm that has dominated both scientific and philosophical views of the body for the past three hundred years. This philosophy created the notion that the body is a machine composed of many separate parts, and that health can be achieved by simply addressing each part in isolation. There is no consideration for how the parts are connected and related.

This is why in western medicine we have doctors for every different part of our body. We’ve got cardiologists for our hearts, gastroenterologists for our guts, podiatrists for our feet, gynecologists for female reproductive organs, neurologists for our brains, etcetera. We’ve carved our body up into various parts and put different doctors in charge of taking care of each part. In a perfect medical system these doctors would be communicating frequently and sharing ideas about their patients. While this does happen in some cases, all too often it doesn’t. I don’t believe this is the fault of the doctors themselves. They are as much victims of the deficiencies of our healthcare system as patients are.

Acupuncturists have a different perspective, because Chinese medicine is based not on Cartesian dualism but on Chinese philosophy, which is inherently holistic. Acupuncturists look at the body as one interconnected whole. From this viewpoint it is impossible to consider a specific part (like the knee, or the heart) without considering it in relation to the whole.

This is of course much more consistent with what we know about how ecological and biological systems (which the body is an example of) operate. And it explains why a single therapy like acupuncture can treat your entire body at the same time.

#2: Acupuncture cures disease

What is a cure? One definition is that a cure has been achieved when the treatment is removed and the dysfunction or illness doesn’t come back.

With the exception of antibiotics, chemotherapy and selective surgery, western medicine does not cure disease. It suppresses symptoms.

How do we know this? If you take a drug for a problem you generally have to take it for the rest of your life. The problem doesn’t go away – it’s being suppressed by the drug. The drug has just replaced a certain function of your body. But as soon as you stop taking that drug, the problem will come back. And often it will be worse than before.

Blood pressure medication is the perfect example of this. It will certainly lower your blood pressure, but it doesn’t do anything to fix whatever was causing your high blood pressure in the first place. People find this out the hard way when they try to stop taking their medication, and their blood pressure skyrockets to a level higher than it was before they started taking the drug.

Why does the problem get worse after taking a drug? Because drugs don’t only suppress symptoms. Drugs also suppress functions. Though drugs provide symptom relief in the short term, over time they may worsen the underlying condition because they interfere with our body’s self-healing mechanisms.

For example, many people take ibuprofen or other non-steroidal anti-inflammatory drugs (NSAIDs) to cope with arthritis and inflammatory conditions. While NSAIDs are effective in reducing pain and inflammation in the short-term, they are also known to reduce blood flow to cartilage. Since blood carries all of the nutrients and immune substance necessary for tissue repair, NSAIDs can actually worsen the original problem when taken chronically.

Drugs also have side effects. Drugs may correct a specific imbalance, but in the process they cause at least one other and often several other imbalances. When this happens in western medicine, other drugs are prescribed to address the side effects caused by the first drug – and so on until the patient ends up on a cocktail of drugs treating the side effects of drugs. (See my article Problem With Your Pill? Take Another Pill! for more on this phenomenon.)

There’s nothing wrong with symptom relief. Anyone who has suffered from a debilitating health condition can tell you that. I believe that symptom suppression with medication is necessary, and even life saving, in certain cases. The problem occurs when symptom suppression with drugs takes the place of other approaches (such as nutritional and lifestyle changes) that address the root of the condition.

Acupuncture, unlike most drugs, has the potential to cure disease. Why? Because as I mentioned above, acupuncture stimulates the body’s self-healing mechanisms. And the body’s ability to heal itself far surpasses anything western medicine has to offer.

The discovery of antibiotics is certainly one of the greatest achievements of medicine (though not without problems, as the recent phenomenon of antibiotic resistance indicates). However, these medications are like children’s toys compared with the extraordinary complexity of the immune system’s ability to heal disease.

The body is capable of spontaneously healing wounds, regenerating tissue, neutralizing toxins, and keeping cancer cells at bay – all while we catch the latest episode of Lost on TV or pick up the kids from soccer practice.

As evolutionary biologist Paul Ewald puts it:

Put bluntly, medicine’s success at vaccination and antibiotic treatment are trivial accomplishments relative to natural selection’s success at generating the immune system… We will probably obtain much better disease control by figuring out how to further tweak the immune system and capitalize on its vastly superior abilities than by relying on some human invention such as new antimicrobials (antibiotics, antivirals or antiprotozoal agents).1

Acupuncture does just that: it “tweaks” the immune system and capitalizes on the body’s vastly superior ability to heal itself. That is the strength of acupuncture. However, this strength can also be a limitation. Since acupuncture works by stimulating the body’s built-in healing capacity, if that capacity is impaired or damaged (by poor nutrition, excessive stress, etc.) then the healing power of acupuncture will be limited.

#3: Acupuncture prevents disease

The superior physician makes it his prerogative to treat disease when it has not yet structurally manifested, and prevents being in the position of having to treat disorders that have already progressed to the realm of the physical. The low level physician finds himself salvaging what has already manifested in physical form, and treating what is already ruined. 2

Amazingly enough, this quote comes from a medical text in China written 2,500 years ago! The idea of “preventative medicine” has received a lot of attention in the west during the past decade. But as the quote above indicates, the Chinese have been aware of the importance of preventative medicine for thousands of years.

Acupuncture and the other branches of Chinese medicine (nutrition, herbal medicine, tai qi, qi gong) restore homeostasis and keep the body functioning at an optimal level. When the body is functioning at an optimal level, we’re far less likely to get sick, and far more likely to recover quickly when we do get sick.

Another way to put it: acupuncture is an effective method of healthcare.

Healthcare, which may be defined as a method of promoting and maintaining health, is not the focus of our current medical system. A more accurate term for the focus of Western medicine would be disease management.

Disease management is important and we certainly need it in the modern world. Yet it’s a mistake to confuse disease management with healthcare. They aren’t the same thing at all.

Western medicine is focused on the treatment of serious disease. Many of the tests, for example, performed in western medicine will not be triggered as abnormal unless the person being tested is already very sick. If a person goes to see a doctor complaining of headaches, digestive problems, fatigue and insomnia, the doctor will run some tests. If the tests come back “normal”, the patient is told that there’s nothing wrong with them! But of course the patient knows that’s not true. They know it’s not normal to have all those problems, and they know that something is wrong.

In fact, until recently doctors thought serious health conditions such as irritable bowel syndrome and fibromyalgia, and physiological changes related to normal life stages like menopause, were “all in the patient’s head”.

Why is western medicine so oriented towards serious disease? Part of the reason is that there is no concept of health in western medicine.

If you look in the index of any western medical textbook, you’re not going to find a definition of health. Doctors don’t study health, and what it takes to be healthy, in medical school. They study diseases and the drugs that are used to treat those diseases. This puts western medicine at a serious disadvantage when it comes to promoting health.

I want to emphasize that I am making generalizations here. There are surely many doctors (and I have seen quite a few of them myself) that are deeply committed to the health and well-being of their patients, recognize the interconnectedness of the body and mind, emphasize the importance of preventative care, and prescribe nutritional and lifestyle changes to their patients. In particular I see this with many younger doctors who have graduated from medical school in the past ten to fifteen years. They tend to be much more open-minded to alternatives to drugs and surgery, and more inclined to recommend these alternatives when appropriate. This is an encouraging trend in medicine.

#4: Acupuncture makes your life better

The goal of Chinese medicine is to improve your quality of life and keep you healthy right up until the end. This means you’re rock climbing, snowboarding, playing with your grandchildren, or doing whatever else you enjoy until you pass away in your sleep at a ripe old age.

Western medicine, on the other hand, is focused on the treatment of serious, life-threatening conditions. It is an unsurpassed intervention for trauma and acute emergencies. Doctors can achieve almost miraculous feats to keep people alive, including reattaching severed limbs and literally bringing people back from the dead. It’s also true that antibiotics have nearly eliminated the risk of dying from the infections that were the primary cause of death all the way up until the mid-20th century, and that medications like insulin for Type 1 Diabetes have made a normal life possible for people who otherwise would have died at an early age. These interventions have extended our average lifespan considerably, and their contributions to our quality of life shouldn’t be underestimated.

So I’m certainly not “against” Western medicine. Believe me, if I get in a car accident or someday have a heart attack, I’ll go straight to the hospital. However, if I were to develop type 2 diabetes, I would begin by changing my diet because in many cases type 2 diabetes can be completely controlled with diet alone. (Of course it’s very unlikely that I will ever get diabetes, because my diet and lifestyle make it virtually impossible for that kind of blood sugar dysregulation to occur.) These examples explain my guiding principle in making decisions about my health care: for any given condition, I will choose the treatment that does the most good and causes the least harm. In my experience, acupuncture and Chinese medicine fits this guiding principle far more often than drugs and surgery.

#5: Acupuncture won’t kill you or make you sick

Primum non nocere, or “first, do no harm” is one of the principal precepts of medical ethics that students are taught in medical school. Another way to state this principle is, “given an existing problem, it may be better to do nothing than to do something that risks causing more harm than good.”

Somewhere along the line this important precept got swept under the rug. While western medicine has made tremendous contributions to disease management, it has also proven to be dangerous to our health.

We may have the most advanced disease management system in the world, but the US is far behind most other industrialized countries when it comes to health. The U.S. ranks just 34th in the world in life expectancy and 29th for infant mortality. Of 13 countries in a recent comparison, the United States ranks an average of 12th (second from bottom) for 16 available health indicators. 3

Even worse, a recent study (PDF) by Dr. Barbara Starfield published in 2000 in the prestigious Journal of the American Medical Association demonstrated that medical care is the 3rd leading cause of death in this country, causing more than 250,000 deaths per year. Only heart disease and cancer kill more people. Although this study was published in one of the most reputable medical journals in the world, it received little media attention and my guess is that few doctors have heard of it.

Dr. Starfield estimates that, each year, medical errors and adverse effects of the health care system are responsible for:

  • 116 million extra physician visits
  • 77 million extra prescriptions
  • 17 million emergency department visits
  • 8 million hospitalizations
  • 3 million long-term admissions
  • 199,000 additional deaths
  • $77 billion in extra costs

As grim as they are, these statistics are likely to be seriously underestimated as only about 5 to 20% of medical-care related incidents are even recorded. Analyses which have taken these oversights into consideration estimate that medical care is in fact the leading cause of death in the U.S. each year. 4

I ask you this: can a medical system that potentially kills more people each year than any other cause of death else be considered “healthcare”?

In contrast to western medicine, acupuncture is extremely safe and well-tolerated. A recent cumulative review published in the British Medical Journal examined the incidence of adverse effects with acupuncture in more than one million treatments.

According to the evidence from these studies, the risk of a serious adverse event with acupuncture is estimated to be 0.0005% per 10,000 treatments, and 0.0055% per 10,000 individual patients.

The authors conclude:

The risk of serious events occurring in association with acupuncture is very low, below that of many common medical treatments. The range of adverse events reported is wide and some events, specifically trauma and some episodes of infection, are likely to be avoidable.

The incidence of milder side effects during acupuncture is also relatively low. In a study of 230,000 patients who received an average of 10 treatments each, 8.6% reported experiencing at least one adverse effect and 2.2% reported one which required treatment. Common adverse effects were bleedings or hematoma (6.1% of patients, 58% of all adverse effects), pain (1.7%) and drowsiness (0.7%).

To put that in perspective, a review of more than a hundred phase I double-blind, placebo-controlled trials reported that 19% of those receiving placebo experienced side effects, with higher rates following repeated dosing and in the elderly. 5

This suggests that placebos (sugar pills) may cause more side effects than acupuncture.

I hope this article has helped you to understand the power of acupuncture and Chinese medicine and its relevance as a genuine system of healthcare. And I hope this series of articles has made clear that acupuncture is not a “woo-woo” energy therapy, but a complete system of medicine based on known anatomical and physiological principles.

I would love to hear your feedback on how these articles have affected your perception and understanding of acupuncture. Please leave a comment!

If you’d like to refer people to this series of posts in the future, I’ve created a special “acupuncture” page on the blog with an index of all of the articles in the series. It’s listed on the right hand side of the page, in the sidebar, under “Health Reports”.

  1. Ewald, P. Plague Time. p.64
  2. See chapter 2 of the Suwen, in Nanjing Zhongyi Xueyuan, ed., Huangdi neijing suwen yishi (An Annotated Text With Translation of the Yellow Emperor’s Classic of Medicine: Plain Questions) (Shanghai: Shanghai Kexue Jishu Chubanshe, 1991), p. 16;
  3. Starfield B. Primary Care: Balancing Health Needs, Services, and Technology. New York, NY: Oxford University Press; 1998.
  4. General Accounting Office study sheds light on nursing home abuse. July 17, 2003. Available at: http://www.injuryboard.com/view.cfm/Article=3005. Accessed December 17, 2003
  5. Rosenzweig P, Brohier S, Zipfel A. The placebo effect in healthy volunteers: influence of experimental conditions on the adverse events profile during phase I studies. Clin Pharmacol Ther 1993;54:578-83.
  1. Thank you so much for these articles. I have been an acupuncturist for over 10 years and I am also a nurse practitioner steeped in western medicine. I could never really get the why of its mechanisms and took it on faith.
    Sometimes I felt like a charlatan selling this magic.
    Now I am grounded. Thank you thank you thank you!!!!!!

  2. Well! This has been an extraordinary series of articles to stumble across as I was doing research for an essay. Studying ‘Human Anatomy and Physiology for Beauty and Complementary Therapy’ and the essay is supposed to be how a particular complementary therapy affects any of the body’s systems, e.g. Muscular, cardiovascular, lymphatic and so on.
    Most students in the past have simply chosen ‘massage’ as the therapy and, having seen several previous essays, all without fail have spouted this stuff about massage coming from China/Japan/India and talking about the meridians and chi/qi/prana……….I was about to go on my own merry way and copy them, my chosen therapy being acupressure; HowEVER,… having looked at numerous websites, read articles and books in the library all offering this as ‘gospel’, I have been comparing pictures of the ‘meridians’ and the tsubos/pressure points and was seeing correlations with things like the axial and linguinal nodes, and other elements of the lymphatic system, as well as other corresponding areas too numerous to go into here, and had started to wonder about the scepticism of some Western medical practitioners. I have been trawling sites for ages, trying to make sense of things and get more information…. and thank GOODness have happened upon YOURS!! It all makes so much sense! How typical that people just keep repeating and repeating some so-called facts, [and this info. as you say is taught on courses all over the place….] without checking and going back to the original source! Yes, well of course learning to read and understand Chinese/Japanese would take a while but….THank you so much for this de-bunking. I underwent acupuncture and thought ‘why was I sent HERE I’ve got a muscular complaint…’.(had sprained my groin and needed it all loosened up for a dance project)’ I need physio to move the muscle not all this needle stuff……’Ten sessions later I had complete and utter all round unimpeded movement. I was amazed but confused and now I know why. Why is this information not being trumpeted from the rooftops?! The world needs to know this, she declared from the top of her soapbox! Well Done, I certainly will spread the word. M-AC in Methven, Perthshire Scotland

  3. Brilliant articles Chris. Truly amazing and inspiring to read about the complexity and science of acupuncture. Even before I read these articles, I knew there had to be something special with a modality that has shown to be successful for thousands of years. What are some other beneficial ways to improve health other than good nutrition, acupuncture, acupressure or herbal medicine? Do you have much familiarity with Qi Gong and its effects? I’ve also been tuned to visceral manipulation work, which I’m assuming is somewhat similar to the origins of Qi Gong (mobility and motility of the connective tissue of the internal organs). Thank you for the fascinating read. (Ha, random) but I just realized you are in the east bay too! Small world.

  4. Hi Chris,
    Great series of articles. I went to my first accupuncture appointment just last week and had the chinese medical physician explain the foundation of Chinese Medicine in much the same way you did and expressed just as much frustration at it being thought of as an “energy based” medicine.

    I was still skeptical about Chinese medicine’s effectiveness and wanted to do further research. i was very happy to find your detailed and very easy to digest explanation. You make a fantastic arguement for the benefits of this medical practice.

    I had always believed that acupuncture was just some silly voodoo, hocus pocus witch doctor nonsense that works largely on the power of suggestion as do many westerners. The only reason I tried TCM was because it was so highly recommended on so many fertility blogs.

    I’m still a bit skeptical, but while I went in for fertility treatments, I know the neck pain I’ve had for months is almost gone.

    So kudos to you for your fantastic article and efforts to educate the public.

    So here is a question for you: how does a superficial micro trauma to the leg or arm cause nutrient rich blood flow to be directed to a viceral organ like the heart?

  5. Chris,
    I am thrilled to have come upon this series. I am an acupuncturist myself, and feel like such a cop-out when patients ask me how it works, and ask me to explain Qi. You are 100% right in saying that school teaches you all about energy and meridians. You have answered all my questions beautifully and I couldn’t have asked for anything more. I had a teacher in school who refused to converse with students about this topic, only saying, “Qi is not energy.” He came from a long lineage of Chinese Doctors, and I could feel his frustration in our understanding of the medicine. I have been fervently curious about the truth behind it all ever since. Again, wow, and thanks for taking the time to pull all this information together with concrete bibliographies. I will be passing your series along to patients and colleagues alike. Much appreciated!

  6. Chris, thank you for explaining acupunture so simply. Do you know how the qi system is related to Applied Kinesology (AK, or muscle testing)? When I have had health practitioners test the strength or weakness of my body with AK, they have explained that they are testing the energy flow through meridians. Are they actually testing low oxygen levels in painful areas of my body? Some supplements test weak? What would this mean according to your understanding?

  7. Chris,

    I am going to acupuncture school in two years after I finish my term in the Coast Guard and help pay my Wife’s student loans from Chiropractic school. I am not a fan of debts. Anyways, I was curious where you go to school and if you know which acupuncture schools teach solid science. Or do you feel that all schools are relatively decent and that it is up to us to seek the best information? P.s. I like the Podcast you did with the BulletProof Exec.

  8. Hi there, I spend a fair bit of time reading medical literature and trying my best to figure out the best ways to proceed with my own health issue (autoimmune hypothyroidism). I have honestly had the best results with pure evidence based (rather than experiential based) medicine. Notice that I did not use the term western medicine as that term is in itself rather racist considering that this form of healthcare has had contributors from pretty much any nationality one could mention. Also as this composite form of healthcare progress’s it certainly does treat the patient as a whole, the big problem being crappy doctors rather than a crappy central concept.

    My question is about the efficacy of acupuncture. To my knowledge there has never been a conclusive trial showing acupuncture to be any more effective than a good massage or for efficacy in treating serious ailments. In addition I have read time and time again that there are no correlate physiological structures to be found at acupressure points.

    I do not wish to be argumentative. Perhaps I am reading the wrong materials or am missing something here?

    Thank you for your time and great blog!

  9. Interesting series, though it probably would have been better titled “Acupuncture Demystified.”

    When I think of Chinese medicine I tend to think more of herbs and remedies. Unfortunately I know little about this aspect other than the scenes you see in movies of people going to a Chinese medicine shop and being prescribed all sorts of exotic substances. Would be interesting to know more about the validity of that domain of CM.

  10. Thanks for a very informative and easy to understand article. I have been using acupuncture to manage stress and the annoying symptoms of menopause with great success. I wish I had known before I had my gall bladder removed, I would have liked to try diet change and acupuncture instead of surgery. The surgeon really scared me into getting it immediately.

    I do love the Zen feeling after acupuncture and have noticed that other things seem to improve such as headaches and I have found that I can concentrate and my occasional “brain fog” is no longer a concern.

    I have been using acupuncture for the past 2 years along with a real food diet (paleo) with great success. Next on my list is to be able to completely come off blood pressure medication.

    Thanks again for the great article in easy to understand terms. By the way, I LOVE the Meal Plan Generator!

  11. Meridian Essence: Modern Thought
    JIANG Hui-ru (蒋会茹), CUI Xue-Jun (崔学军), and YU Zheng (于峥) Chin J Integr Med 2013 Jun;19(6):471-474 DOI: 10.1007/s11655-013-1322-5

    Abstract
    Meridian essence has been investigated through anatomy, electrophysiology, biophysics, and biochemistry. Various hypotheses of meridian essence exist, but no hypothesis can truly reflect the internal character of Chinese medicine (CM). The research of meridian essence requires a holistic viewpoint and innovative awareness. Initially, any hypothesis regarding meridian essence should begin with observation of the human body. Secondly, the research should arise from the meridians’ physical functions and pathological changes, so as to maintain the fundamental nature of the meridians themselves. Thirdly, the research should be based upon the theory of CM, yet coupled with the integration of modern techniques to deepen our understanding of the scientific contents of meridians. Fourthly, theoretical research should be combined closely with clinical practice, in order to test the achievements in actual conditions. Lastly, more attention should be given to negative results in studies to more accurately discover the real essence of meridians.
    KEYWORDS: acupuncture, meridian, acupoints

    Meridian theory is a core component of Chinese medicine (CM). The concept of meridian was derived from meridian phenomena by ancient Chinese doctors through long and arduous clinical practice. Among these meridian phenomena, propagated needle sensation (PNS) is perhaps most significant. The phenomenon of PNS includes subjective feelings of numbness, soreness, distention or heaviness (experienced by the patient), that travels along lines of the body once certain points are stimulated with acupuncture. PNS has been verified by many researchers, since the principal was founded by a Japanese researcher in 1950s.(1) Meridian theory has guided acupuncture treatment in the clinic for thousands of years. Therefore, defining meridian essence is a key scientific issue. Thus meridian essence has been investigated via the study of anatomy, electrophysiology, biophysics, and biochemistry.

    Anatomy
    Regarding the anatomical structure of meridians, various hypotheses have been introduced. The most popular belief is that meridians are composed primarily of the nervous system, and further supplemented by both the vascular and lymphatic systems.(1) Around most of acupoints and meridians, there are nerve trunks or large nerve branches. For instance, the Lung (Fei) meridian at the upper limb distributes along the musculocutaneous nerve and lateralcutaneous nerve of the forearm, while the Ren channel, Kidney (Shen) meridian and Stomach (Wei) meridian at the chest and abdomen spread along intercostal nerves and cutaneous branches of the thoracic nerve.(2) Nerve segments contribute to the meridian system. Nerve segments connect Back-shu acupoints and Front-mu acupoints with corresponding Zang-fu organs. The therapeutic effects of acupoints could be attributed to the innervation of nerve segments. Needling Pangguangshu (BL28), Ciliao (BL32), and Qugu (RN2) could enhance the intravesical pressure. Nerves deep to these acupoints belong to nerve segments controlled by the vesical center. The circulatory system is also related to parts of meridians. It has been found that 286 of 309 acupoints, when inserted with needles, are surrounded by arterial and venous trunks.(2) The courses of the three foot yin meridians and the three hand yang meridians are in accord with the flow of the lymphatic system.

    Electrophysiology
    Acupoints usually display low impedance; namely, the current intensity is stronger at acupointssthan at other points. Meanwhile, the strongest intensity is found in acupoints on the head, while the weakest is at the ends of limbs. Among acupoints on the back, acupoints have lower impedance at the upper back than those at the lumbosacral portion.(3,4)

    High electrical potential is the other electrophy- siological characteristic of acupoints. The electrical potential of acupoints is higher than at other areas.(5) The electrical potential of acupoints is similar to the characteristic of low impedance. Acupoints on the head have the highest potential, and at the four limbs the lowest potential. The electricalpotential decreases in Jing (well), Xing (brook), Shu (stream), and Jing (river) acupoints in turn, and increases in He (sea) acupoints. The electrical potential of acupoints is affected by the physical and pathological status of the body, and by many other factors. The lowest potential is detected at the midnight. Food intake and excretion could influence the potential of acupoints. For instance, after eating, the electrical potential of most acupoints on the Stomach (Wei) meridian are enhanced, especially the Zusanli (ST36), while Zhiyin (BL67), and Jinggu (BL64) of the Bladder (Dan) meridian are reduced. Micturition increases the potential of Kunlun (BL60) and Weizhong (BL40), whereas defecation lowers the potential of the Large Intestine (Dachang) meridian. In healthy young volunteers, the electrodermal activity in a pre- exercise resting state was stable and similar amongst 8 different tested points, while during exercise a significant increase of current (from 1000–2000 to 4000–8000 nA) was observed, with the maximal values related to the point located on the ulnar side of the little finger, at the base of the nail, corresponding to the Shaochong (HT9) of the Heart meridian.(6) Normally, bilateral acupoints have balanced potential. However, unbalanced potential is detected in a diseased state. The potential of Ganshu (BL18), and Xingjian (LR2) were unbalanced in Liver (Gan) diseases, as were Zhongfu (LU1), and Feishu (BL13) in Lung (Fei) diseases.

    The extremely low-frequency electrical energy is transported somewhat more efficiently through the Large Intestine meridian when compared with a non-meridian control. The results were not dramatic, with some participants giving greater values to the control channel, but they were statistically significant.(7) There was a trend for the Bladder meridian acupoints to have larger numbers of neurofilaments than the reference points, and that trend seemed to be directly proportional to the difference involtage between the points. Bladder meridian acupoints on the back in rats exhibited specific electrical and histological characteristics. Therefore, those acupoints may be utilized to investigate the efficacy of acupuncture with laboratory animals.(8)

    Biophysics
    Meridians possess the biophysical property of high emission of light. A markedly low luminance appeared on the Du channel in animals with experimental syndrome of yang deficiency induced by hydrocortisone; while in animals with experimental syndrome of blood deficiency caused by bleeding, an apparently low luminance occurred on the Ren channel. The intensity of the emitted light on both the Du and Ren channels increased after acupuncture treatment.(9) Electro-acupuncture could affect the light intensity. Sparse-dense wave stimulates light emission of needled acupoints and the distal acupoints of the meridian.(10)

    The skin temperature at acupoints is higher than that at non-acupoints. There are lines and points with higher temperatures on the chest and the abdomen, where temperatures are 0.5–1 ℃ higher than surrounding areas.(1) These point characteristics are consistent regardless of seasonal, physical or pathological conditions. Most of the points correspond to Front-mu acupoints. The temperature changes of acupoints could reflect the pathological changes of corresponding Zang-fu organs. In patients with coronary heart disease, for example, the temperature of related acupoints is lower than that of those seen in healthy people.(1) In patients with chronic gastritis, gastric ulcer, and gastric cancer, the temperature difference at bilateral Chengman (ST20), and Liangmen (ST21) is higher than that of healthy patients.(11)

    In contrast to the central nervous system activation by sham acupoints, Taichong (LR3), Zhongdu (LR6), Zusanli (ST36) and Xiangu (ST43) had the common effect of activating two specific areas of the brain: the bilateral primary somatosensory area and the ipsilateral cerebellum. Acupuncture stimulation of both acupoints Taichong (LR3) and Zhongdu (LR6) evoked activation at the ipsilateralsuperior parietal lobe (BA7). Acupuncture stimulation of both acupoints Zusanli (ST36) and Xiangu (ST43) evoked activation at the ipsilateral middle frontal gyrus (BA10). These results suggest that different acupoints on the same meridian may activate certain similar areas of the brain.(12)

    Biochemistry
    Ion concentration is special in acupoints and meridians. There is a high concentration of calcium (Ca2+), and potassium ions (K+), and a low concentration of sodium (Na+).(13) Stimulating the acupoints on the meridian could cause the Ca2+ concentration to increase in other points of the same meridian but to reduce in the control points (lateral to the meridian points). The results indicate that Ca2+ maybe involved in the activities of the meridians.(14) When acupoints are needled, the concentrations of K+ and Na+ change contrarily. The increased concentration of K+ is accompanied by decreased Na+, vice versa, indicating acupuncture may strengthen the sodium (potassium) pump. Acupuncture also reduces pH values in the acupoints.(15)
    Vigorous metabolism can be detected in acupoints and meridians. Transcutaneous CO2 emission is an important index for the metabolizing level. CO2 emission is more from acupoints than that from non-acupoints. (16) The distribution of transcutaneous CO2 emission is highly related to the position on the body. Transcutaneous CO2 emission is significantly higher at Daling (PC7) and Quze (PC3) than the control points beside them.(17) Needling acupoints adds to the CO2 emission and oxygen consumption.(18) It has also been discovered that oxygen partial pressure is higher in acupoints than that in non-acupoints. Electro-acupuncture at Hegu (LI4) and Neiguan (PC6) depresses the oxygen partial pressure, and the oxygen partial pressure recovers gradually after removal of electroacupuncture.(19) Mechanical pressure could block the induction of acupuncture treatment on oxygenpartial pressure.(20)

    Current Thought
    All of these studies prove the objective existence of meridians in the human body, and meridians could regulate physical functions. However, any hypothesis has limitations in explaining meridian phenomena and can not truly reflect the internal character of CM. One hypothesis usually illuminates partial meaning. Among these hypotheses, some experimental results are mutually contradictory. Meanwhile, no negative result or counter view regarding the existence of meridians was reported. There were rather, many arguments in documented studies to prove their existence.(21-23) We need to maintain a holistic viewpoint and support innovative ideas. Firstly, it is most important that any hypothesis about meridian essence should originate from observation of the human body, as meridian theory was born in medical practice to treat diseases in numerous patients. Animal experiments, therefore, can not truly reflect meridian phenomena in the human body. Secondly, research of meridian essence should begin with the meridians’ physical functions and pathological changes in order to maintain the fundamental nature of meridians. Thirdly, the research should be based upon the theory of CM, yet coupled with the integration of modern techniques to further examine the scientific contents of meridians. Fourthly, the theoretical research should be done in combination with clinical practice to test the achievements in actual conditions. Fifthly, more attention should be given to negative results in studies in order to more accurately discover the real essence of meridians, and thus avoid being blinded by superfluous information. Research of meridian essence is a pivotal aspect of Chinese academia, and continued debate will further drive the development of medical science.

    Acknowledgement
    We gratefully thank the assistance of Michael R. Berger, M.S. Medicine-Acupuncture, Tuina, in revising the manuscript.

    REFERENCES
    1. Sun GJ, ed. Acupuncture science. 2nd ed. Beijing: People’s Medical Publishing House; 2011:88.
    2. Jiang KC, Li D. Anatomical observation of the twelve meridians and body structure. Acta Univ Tradit Med Sin Pharmacol Shanghai (Chin) 1960;1:57.
    3. Hu XL, Wu BH, LI WF, LI BJ. Preliminary study on plotting out the channel course with skin impedance as index. Acupunct Res (Chin) 1987;(Suppl):9-15,8.
    4. Zhu ZX, Yu SZ, Zhang RX, Zheng MX, Yang FS, Liu YM, et al. A study on the skin electrical conductance of the line of latent propagated sensation along channel. Acupunct Res (Chin) 1980;5:308-310.
    5. Wang BX, ed. Abroad studies of meridians. 1st ed. Beijing: People’s Medical Publishing House;1984:29.
    6. Pontarollo F, Rapacioli G, Bellavite P. Increase of electrodermal activity of heart meridian during physical exercise: the significance of electrical values in acupuncture and diagnostic importance. Complement Ther Clin Pract 2010;16:149-153.
    7. Keith S, Kent C. The transport of extremely low-frequency electrical signals through an acupuncture meridian compared to non-meridian tissue. J Altern Complement Med 2011;7:127-132.
    8 Han HJ, Park SJ, Soh KS, Myoung HS, Lee KJ, Ogay V, et al. Electrical characterization of proposed transpositional acupoints on the urinary bladder meridian in a rat model. Evid Based Complement Alternat Med 2011;295475
    9. Yan ZQ, Chi YR, Zhu XR, Cheng J, Wang PJ. Applications of surface ultra-weak luminescence law in the study of Chinese medicine syndromes, needling sensation and acupoints characteristics. Beijing J Tradit Chin Med (Chin) 1993;12:51-53.
    10. Sun KX, Yang WY, Ni XD, Zhang HM, Su L. Effects of electroacupuncture stimulation with different parameters on light emission of body acupoints. China J Basic Med Tradit Chin Med (Chin) 1998;4(3):52-54.
    11. Sun KX, Yang WY, Ni XD, Zhang HM, Su L. Effects of electroacupuncture stimulation with different parameters on light emission of body acupoints. China J Basic Med Tradit Chin Med (Chin) 1998;4(3):52-54.
    12. Li L, Liu H, Li YZ, Xu JY, Shan BC, Gong D, et al. The human brain response to acupuncture on same-meridian acupoints: evidence from an fMRI study. J Altern Complement Med 2008;14:673-678.
    13. Guo Y, Xu TP, Chen JS, Zhang CX, Jiang P. Speciality of concentration of calcium in acupoints of rabbits. Acupunct Res (Chin) 1991;16:66-68.
    14. Guo Y, Xu TP, Chen JS, Zhang CX, Jiang P. Experimental study of the acupuncture effects on calcium ion concentration in rabbits’ acupoints. World J Acupunct Moxibust 1992;2:51-55.
    15. Jiang HZ, Wang Q, Zhang MM, Gong P, Huang GY. Effect of acupuncture on pH values of acupoints in the goat. Chin Acupunct Moxibust (Chin) 2006;26:732-734.
    16. Huang T, Wang RH, Zhang WB, Han B, Huang X, Tian YY, et al. Relationship between needle sensation and periphery transcutaneous CO2 emission. China J Basic Med Tradit Chin Med (Chin) 2009;15:615-616,618.
    17. Zhang WB, Tian YY, Zhu ZX, Xu RM. The distribution of transcutaneous CO2 emission and correlation with the points along the pericardium meridian. J Acupunct Meridian Stud 2009;2:197-201
    18. Zhang WB, Li H, Xu RM. Effects of needling meridian on transcutaneous CO2 emission. China Acupunct Moxibust (Chin) 1996;16:39-42.
    19. Chen M, Hu XL, Wu ZX. Observation on changes of oxygen partial pressure in the deep tissues along the Large intestine meridian during acupuncture in healthy subjects. Acupunct Res (Chin) 2010;35:213-216.
    20. Xu XY, Hu XL, Wu BH. The influence of mechanical pressing on partial pressure of oxygen in three points along the Large Intestine meridian during acupuncture. Acupunct Res (Chin) 2000;25:276-279.
    21. Wang FC, Li T. Channels and collaterals are “doctrine” or “theory”. China Acupunct Moxibust (Chin) 2006;26:446-450. He XH, Zhang J, Jia MH. Doubt on conception of meridian. J Ningxia Med Coll (Chin) 2006;28:359-361.
    22. He XH, Zhang J, Jia MH. Doubt on conception of meridian. J Ningxia Med Coll (Chin) 2006;28:359-361
    23. Zhang WB. Traditional meridian concepts and modern meridian research. China J Basic Med Tradit Chin Med (Chin) 2003;9:924-929.

    Meridian Essence: Modern Thought
    JIANG Hui-ru (蒋会茹), CUI Xue-Jun (崔学军), and YU Zheng (于峥) Chin J Integr Med 2013 Jun;19(6):471-474 DOI: 10.1007/s11655-013-1322-5

    Abstract
    Meridian essence has been investigated through anatomy, electrophysiology, biophysics, and biochemistry. Various hypotheses of meridian essence exist, but no hypothesis can truly reflect the internal character of Chinese medicine (CM). The research of meridian essence requires a holistic viewpoint and innovative awareness. Initially, any hypothesis regarding meridian essence should begin with observation of the human body. Secondly, the research should arise from the meridians’ physical functions and pathological changes, so as to maintain the fundamental nature of the meridians themselves. Thirdly, the research should be based upon the theory of CM, yet coupled with the integration of modern techniques to deepen our understanding of the scientific contents of meridians. Fourthly, theoretical research should be combined closely with clinical practice, in order to test the achievements in actual conditions. Lastly, more attention should be given to negative results in studies to more accurately discover the real essence of meridians.
    KEYWORDS: acupuncture, meridian, acupoints

    Meridian theory is a core component of Chinese medicine (CM). The concept of meridian was derived from meridian phenomena by ancient Chinese doctors through long and arduous clinical practice. Among these meridian phenomena, propagated needle sensation (PNS) is perhaps most significant. The phenomenon of PNS includes subjective feelings of numbness, soreness, distention or heaviness (experienced by the patient), that travels along lines of the body once certain points are stimulated with acupuncture. PNS has been verified by many researchers, since the principal was founded by a Japanese researcher in 1950s.(1) Meridian theory has guided acupuncture treatment in the clinic for thousands of years. Therefore, defining meridian essence is a key scientific issue. Thus meridian essence has been investigated via the study of anatomy, electrophysiology, biophysics, and biochemistry.

    Anatomy
    Regarding the anatomical structure of meridians, various hypotheses have been introduced. The most popular belief is that meridians are composed primarily of the nervous system, and further supplemented by both the vascular and lymphatic systems.(1) Around most of acupoints and meridians, there are nerve trunks or large nerve branches. For instance, the Lung (Fei) meridian at the upper limb distributes along the musculocutaneous nerve and lateralcutaneous nerve of the forearm, while the Ren channel, Kidney (Shen) meridian and Stomach (Wei) meridian at the chest and abdomen spread along intercostal nerves and cutaneous branches of the thoracic nerve.(2) Nerve segments contribute to the meridian system. Nerve segments connect Back-shu acupoints and Front-mu acupoints with corresponding Zang-fu organs. The therapeutic effects of acupoints could be attributed to the innervation of nerve segments. Needling Pangguangshu (BL28), Ciliao (BL32), and Qugu (RN2) could enhance the intravesical pressure. Nerves deep to these acupoints belong to nerve segments controlled by the vesical center. The circulatory system is also related to parts of meridians. It has been found that 286 of 309 acupoints, when inserted with needles, are surrounded by arterial and venous trunks.(2) The courses of the three foot yin meridians and the three hand yang meridians are in accord with the flow of the lymphatic system.

    Electrophysiology
    Acupoints usually display low impedance; namely, the current intensity is stronger at acupointssthan at other points. Meanwhile, the strongest intensity is found in acupoints on the head, while the weakest is at the ends of limbs. Among acupoints on the back, acupoints have lower impedance at the upper back than those at the lumbosacral portion.(3,4)

    High electrical potential is the other electrophy- siological characteristic of acupoints. The electrical potential of acupoints is higher than at other areas.(5) The electrical potential of acupoints is similar to the characteristic of low impedance. Acupoints on the head have the highest potential, and at the four limbs the lowest potential. The electricalpotential decreases in Jing (well), Xing (brook), Shu (stream), and Jing (river) acupoints in turn, and increases in He (sea) acupoints. The electrical potential of acupoints is affected by the physical and pathological status of the body, and by many other factors. The lowest potential is detected at the midnight. Food intake and excretion could influence the potential of acupoints. For instance, after eating, the electrical potential of most acupoints on the Stomach (Wei) meridian are enhanced, especially the Zusanli (ST36), while Zhiyin (BL67), and Jinggu (BL64) of the Bladder (Dan) meridian are reduced. Micturition increases the potential of Kunlun (BL60) and Weizhong (BL40), whereas defecation lowers the potential of the Large Intestine (Dachang) meridian. In healthy young volunteers, the electrodermal activity in a pre- exercise resting state was stable and similar amongst 8 different tested points, while during exercise a significant increase of current (from 1000–2000 to 4000–8000 nA) was observed, with the maximal values related to the point located on the ulnar side of the little finger, at the base of the nail, corresponding to the Shaochong (HT9) of the Heart meridian.(6) Normally, bilateral acupoints have balanced potential. However, unbalanced potential is detected in a diseased state. The potential of Ganshu (BL18), and Xingjian (LR2) were unbalanced in Liver (Gan) diseases, as were Zhongfu (LU1), and Feishu (BL13) in Lung (Fei) diseases.

    The extremely low-frequency electrical energy is transported somewhat more efficiently through the Large Intestine meridian when compared with a non-meridian control. The results were not dramatic, with some participants giving greater values to the control channel, but they were statistically significant.(7) There was a trend for the Bladder meridian acupoints to have larger numbers of neurofilaments than the reference points, and that trend seemed to be directly proportional to the difference involtage between the points. Bladder meridian acupoints on the back in rats exhibited specific electrical and histological characteristics. Therefore, those acupoints may be utilized to investigate the efficacy of acupuncture with laboratory animals.(8)

    Biophysics
    Meridians possess the biophysical property of high emission of light. A markedly low luminance appeared on the Du channel in animals with experimental syndrome of yang deficiency induced by hydrocortisone; while in animals with experimental syndrome of blood deficiency caused by bleeding, an apparently low luminance occurred on the Ren channel. The intensity of the emitted light on both the Du and Ren channels increased after acupuncture treatment.(9) Electro-acupuncture could affect the light intensity. Sparse-dense wave stimulates light emission of needled acupoints and the distal acupoints of the meridian.(10)

    The skin temperature at acupoints is higher than that at non-acupoints. There are lines and points with higher temperatures on the chest and the abdomen, where temperatures are 0.5–1 ℃ higher than surrounding areas.(1) These point characteristics are consistent regardless of seasonal, physical or pathological conditions. Most of the points correspond to Front-mu acupoints. The temperature changes of acupoints could reflect the pathological changes of corresponding Zang-fu organs. In patients with coronary heart disease, for example, the temperature of related acupoints is lower than that of those seen in healthy people.(1) In patients with chronic gastritis, gastric ulcer, and gastric cancer, the temperature difference at bilateral Chengman (ST20), and Liangmen (ST21) is higher than that of healthy patients.(11)

    In contrast to the central nervous system activation by sham acupoints, Taichong (LR3), Zhongdu (LR6), Zusanli (ST36) and Xiangu (ST43) had the common effect of activating two specific areas of the brain: the bilateral primary somatosensory area and the ipsilateral cerebellum. Acupuncture stimulation of both acupoints Taichong (LR3) and Zhongdu (LR6) evoked activation at the ipsilateralsuperior parietal lobe (BA7). Acupuncture stimulation of both acupoints Zusanli (ST36) and Xiangu (ST43) evoked activation at the ipsilateral middle frontal gyrus (BA10). These results suggest that different acupoints on the same meridian may activate certain similar areas of the brain.(12)

    Biochemistry
    Ion concentration is special in acupoints and meridians. There is a high concentration of calcium (Ca2+), and potassium ions (K+), and a low concentration of sodium (Na+).(13) Stimulating the acupoints on the meridian could cause the Ca2+ concentration to increase in other points of the same meridian but to reduce in the control points (lateral to the meridian points). The results indicate that Ca2+ maybe involved in the activities of the meridians.(14) When acupoints are needled, the concentrations of K+ and Na+ change contrarily. The increased concentration of K+ is accompanied by decreased Na+, vice versa, indicating acupuncture may strengthen the sodium (potassium) pump. Acupuncture also reduces pH values in the acupoints.(15)
    Vigorous metabolism can be detected in acupoints and meridians. Transcutaneous CO2 emission is an important index for the metabolizing level. CO2 emission is more from acupoints than that from non-acupoints. (16) The distribution of transcutaneous CO2 emission is highly related to the position on the body. Transcutaneous CO2 emission is significantly higher at Daling (PC7) and Quze (PC3) than the control points beside them.(17) Needling acupoints adds to the CO2 emission and oxygen consumption.(18) It has also been discovered that oxygen partial pressure is higher in acupoints than that in non-acupoints. Electro-acupuncture at Hegu (LI4) and Neiguan (PC6) depresses the oxygen partial pressure, and the oxygen partial pressure recovers gradually after removal of electroacupuncture.(19) Mechanical pressure could block the induction of acupuncture treatment on oxygenpartial pressure.(20)

    Current Thought
    All of these studies prove the objective existence of meridians in the human body, and meridians could regulate physical functions. However, any hypothesis has limitations in explaining meridian phenomena and can not truly reflect the internal character of CM. One hypothesis usually illuminates partial meaning. Among these hypotheses, some experimental results are mutually contradictory. Meanwhile, no negative result or counter view regarding the existence of meridians was reported. There were rather, many arguments in documented studies to prove their existence.(21-23) We need to maintain a holistic viewpoint and support innovative ideas. Firstly, it is most important that any hypothesis about meridian essence should originate from observation of the human body, as meridian theory was born in medical practice to treat diseases in numerous patients. Animal experiments, therefore, can not truly reflect meridian phenomena in the human body. Secondly, research of meridian essence should begin with the meridians’ physical functions and pathological changes in order to maintain the fundamental nature of meridians. Thirdly, the research should be based upon the theory of CM, yet coupled with the integration of modern techniques to further examine the scientific contents of meridians. Fourthly, the theoretical research should be done in combination with clinical practice to test the achievements in actual conditions. Fifthly, more attention should be given to negative results in studies in order to more accurately discover the real essence of meridians, and thus avoid being blinded by superfluous information. Research of meridian essence is a pivotal aspect of Chinese academia, and continued debate will further drive the development of medical science.

    Acknowledgement
    We gratefully thank the assistance of Michael R. Berger, M.S. Medicine-Acupuncture, Tuina, in revising the manuscript.

    REFERENCES
    1. Sun GJ, ed. Acupuncture science. 2nd ed. Beijing: People’s Medical Publishing House; 2011:88.
    2. Jiang KC, Li D. Anatomical observation of the twelve meridians and body structure. Acta Univ Tradit Med Sin Pharmacol Shanghai (Chin) 1960;1:57.
    3. Hu XL, Wu BH, LI WF, LI BJ. Preliminary study on plotting out the channel course with skin impedance as index. Acupunct Res (Chin) 1987;(Suppl):9-15,8.
    4. Zhu ZX, Yu SZ, Zhang RX, Zheng MX, Yang FS, Liu YM, et al. A study on the skin electrical conductance of the line of latent propagated sensation along channel. Acupunct Res (Chin) 1980;5:308-310.
    5. Wang BX, ed. Abroad studies of meridians. 1st ed. Beijing: People’s Medical Publishing House;1984:29.
    6. Pontarollo F, Rapacioli G, Bellavite P. Increase of electrodermal activity of heart meridian during physical exercise: the significance of electrical values in acupuncture and diagnostic importance. Complement Ther Clin Pract 2010;16:149-153.
    7. Keith S, Kent C. The transport of extremely low-frequency electrical signals through an acupuncture meridian compared to non-meridian tissue. J Altern Complement Med 2011;7:127-132.
    8 Han HJ, Park SJ, Soh KS, Myoung HS, Lee KJ, Ogay V, et al. Electrical characterization of proposed transpositional acupoints on the urinary bladder meridian in a rat model. Evid Based Complement Alternat Med 2011;295475
    9. Yan ZQ, Chi YR, Zhu XR, Cheng J, Wang PJ. Applications of surface ultra-weak luminescence law in the study of Chinese medicine syndromes, needling sensation and acupoints characteristics. Beijing J Tradit Chin Med (Chin) 1993;12:51-53.
    10. Sun KX, Yang WY, Ni XD, Zhang HM, Su L. Effects of electroacupuncture stimulation with different parameters on light emission of body acupoints. China J Basic Med Tradit Chin Med (Chin) 1998;4(3):52-54.
    11. Sun KX, Yang WY, Ni XD, Zhang HM, Su L. Effects of electroacupuncture stimulation with different parameters on light emission of body acupoints. China J Basic Med Tradit Chin Med (Chin) 1998;4(3):52-54.
    12. Li L, Liu H, Li YZ, Xu JY, Shan BC, Gong D, et al. The human brain response to acupuncture on same-meridian acupoints: evidence from an fMRI study. J Altern Complement Med 2008;14:673-678.
    13. Guo Y, Xu TP, Chen JS, Zhang CX, Jiang P. Speciality of concentration of calcium in acupoints of rabbits. Acupunct Res (Chin) 1991;16:66-68.
    14. Guo Y, Xu TP, Chen JS, Zhang CX, Jiang P. Experimental study of the acupuncture effects on calcium ion concentration in rabbits’ acupoints. World J Acupunct Moxibust 1992;2:51-55.
    15. Jiang HZ, Wang Q, Zhang MM, Gong P, Huang GY. Effect of acupuncture on pH values of acupoints in the goat. Chin Acupunct Moxibust (Chin) 2006;26:732-734.
    16. Huang T, Wang RH, Zhang WB, Han B, Huang X, Tian YY, et al. Relationship between needle sensation and periphery transcutaneous CO2 emission. China J Basic Med Tradit Chin Med (Chin) 2009;15:615-616,618.
    17. Zhang WB, Tian YY, Zhu ZX, Xu RM. The distribution of transcutaneous CO2 emission and correlation with the points along the pericardium meridian. J Acupunct Meridian Stud 2009;2:197-201
    18. Zhang WB, Li H, Xu RM. Effects of needling meridian on transcutaneous CO2 emission. China Acupunct Moxibust (Chin) 1996;16:39-42.
    19. Chen M, Hu XL, Wu ZX. Observation on changes of oxygen partial pressure in the deep tissues along the Large intestine meridian during acupuncture in healthy subjects. Acupunct Res (Chin) 2010;35:213-216.
    20. Xu XY, Hu XL, Wu BH. The influence of mechanical pressing on partial pressure of oxygen in three points along the Large Intestine meridian during acupuncture. Acupunct Res (Chin) 2000;25:276-279.
    21. Wang FC, Li T. Channels and collaterals are “doctrine” or “theory”. China Acupunct Moxibust (Chin) 2006;26:446-450. He XH, Zhang J, Jia MH. Doubt on conception of meridian. J Ningxia Med Coll (Chin) 2006;28:359-361.
    22. He XH, Zhang J, Jia MH. Doubt on conception of meridian. J Ningxia Med Coll (Chin) 2006;28:359-361
    23. Zhang WB. Traditional meridian concepts and modern meridian research. China J Basic Med Tradit Chin Med (Chin) 2003;9:924-929.

    Meridian Essence: Modern Thought
    JIANG Hui-ru (蒋会茹), CUI Xue-Jun (崔学军), and YU Zheng (于峥) Chin J Integr Med 2013 Jun;19(6):471-474 DOI: 10.1007/s11655-013-1322-5

    Abstract
    Meridian essence has been investigated through anatomy, electrophysiology, biophysics, and biochemistry. Various hypotheses of meridian essence exist, but no hypothesis can truly reflect the internal character of Chinese medicine (CM). The research of meridian essence requires a holistic viewpoint and innovative awareness. Initially, any hypothesis regarding meridian essence should begin with observation of the human body. Secondly, the research should arise from the meridians’ physical functions and pathological changes, so as to maintain the fundamental nature of the meridians themselves. Thirdly, the research should be based upon the theory of CM, yet coupled with the integration of modern techniques to deepen our understanding of the scientific contents of meridians. Fourthly, theoretical research should be combined closely with clinical practice, in order to test the achievements in actual conditions. Lastly, more attention should be given to negative results in studies to more accurately discover the real essence of meridians.
    KEYWORDS: acupuncture, meridian, acupoints

    Meridian theory is a core component of Chinese medicine (CM). The concept of meridian was derived from meridian phenomena by ancient Chinese doctors through long and arduous clinical practice. Among these meridian phenomena, propagated needle sensation (PNS) is perhaps most significant. The phenomenon of PNS includes subjective feelings of numbness, soreness, distention or heaviness (experienced by the patient), that travels along lines of the body once certain points are stimulated with acupuncture. PNS has been verified by many researchers, since the principal was founded by a Japanese researcher in 1950s.(1) Meridian theory has guided acupuncture treatment in the clinic for thousands of years. Therefore, defining meridian essence is a key scientific issue. Thus meridian essence has been investigated via the study of anatomy, electrophysiology, biophysics, and biochemistry.

    Anatomy
    Regarding the anatomical structure of meridians, various hypotheses have been introduced. The most popular belief is that meridians are composed primarily of the nervous system, and further supplemented by both the vascular and lymphatic systems.(1) Around most of acupoints and meridians, there are nerve trunks or large nerve branches. For instance, the Lung (Fei) meridian at the upper limb distributes along the musculocutaneous nerve and lateralcutaneous nerve of the forearm, while the Ren channel, Kidney (Shen) meridian and Stomach (Wei) meridian at the chest and abdomen spread along intercostal nerves and cutaneous branches of the thoracic nerve.(2) Nerve segments contribute to the meridian system. Nerve segments connect Back-shu acupoints and Front-mu acupoints with corresponding Zang-fu organs. The therapeutic effects of acupoints could be attributed to the innervation of nerve segments. Needling Pangguangshu (BL28), Ciliao (BL32), and Qugu (RN2) could enhance the intravesical pressure. Nerves deep to these acupoints belong to nerve segments controlled by the vesical center. The circulatory system is also related to parts of meridians. It has been found that 286 of 309 acupoints, when inserted with needles, are surrounded by arterial and venous trunks.(2) The courses of the three foot yin meridians and the three hand yang meridians are in accord with the flow of the lymphatic system.

    Electrophysiology
    Acupoints usually display low impedance; namely, the current intensity is stronger at acupointssthan at other points. Meanwhile, the strongest intensity is found in acupoints on the head, while the weakest is at the ends of limbs. Among acupoints on the back, acupoints have lower impedance at the upper back than those at the lumbosacral portion.(3,4)

    High electrical potential is the other electrophy- siological characteristic of acupoints. The electrical potential of acupoints is higher than at other areas.(5) The electrical potential of acupoints is similar to the characteristic of low impedance. Acupoints on the head have the highest potential, and at the four limbs the lowest potential. The electricalpotential decreases in Jing (well), Xing (brook), Shu (stream), and Jing (river) acupoints in turn, and increases in He (sea) acupoints. The electrical potential of acupoints is affected by the physical and pathological status of the body, and by many other factors. The lowest potential is detected at the midnight. Food intake and excretion could influence the potential of acupoints. For instance, after eating, the electrical potential of most acupoints on the Stomach (Wei) meridian are enhanced, especially the Zusanli (ST36), while Zhiyin (BL67), and Jinggu (BL64) of the Bladder (Dan) meridian are reduced. Micturition increases the potential of Kunlun (BL60) and Weizhong (BL40), whereas defecation lowers the potential of the Large Intestine (Dachang) meridian. In healthy young volunteers, the electrodermal activity in a pre- exercise resting state was stable and similar amongst 8 different tested points, while during exercise a significant increase of current (from 1000–2000 to 4000–8000 nA) was observed, with the maximal values related to the point located on the ulnar side of the little finger, at the base of the nail, corresponding to the Shaochong (HT9) of the Heart meridian.(6) Normally, bilateral acupoints have balanced potential. However, unbalanced potential is detected in a diseased state. The potential of Ganshu (BL18), and Xingjian (LR2) were unbalanced in Liver (Gan) diseases, as were Zhongfu (LU1), and Feishu (BL13) in Lung (Fei) diseases.

    The extremely low-frequency electrical energy is transported somewhat more efficiently through the Large Intestine meridian when compared with a non-meridian control. The results were not dramatic, with some participants giving greater values to the control channel, but they were statistically significant.(7) There was a trend for the Bladder meridian acupoints to have larger numbers of neurofilaments than the reference points, and that trend seemed to be directly proportional to the difference involtage between the points. Bladder meridian acupoints on the back in rats exhibited specific electrical and histological characteristics. Therefore, those acupoints may be utilized to investigate the efficacy of acupuncture with laboratory animals.(8)

    Biophysics
    Meridians possess the biophysical property of high emission of light. A markedly low luminance appeared on the Du channel in animals with experimental syndrome of yang deficiency induced by hydrocortisone; while in animals with experimental syndrome of blood deficiency caused by bleeding, an apparently low luminance occurred on the Ren channel. The intensity of the emitted light on both the Du and Ren channels increased after acupuncture treatment.(9) Electro-acupuncture could affect the light intensity. Sparse-dense wave stimulates light emission of needled acupoints and the distal acupoints of the meridian.(10)

    The skin temperature at acupoints is higher than that at non-acupoints. There are lines and points with higher temperatures on the chest and the abdomen, where temperatures are 0.5–1 ℃ higher than surrounding areas.(1) These point characteristics are consistent regardless of seasonal, physical or pathological conditions. Most of the points correspond to Front-mu acupoints. The temperature changes of acupoints could reflect the pathological changes of corresponding Zang-fu organs. In patients with coronary heart disease, for example, the temperature of related acupoints is lower than that of those seen in healthy people.(1) In patients with chronic gastritis, gastric ulcer, and gastric cancer, the temperature difference at bilateral Chengman (ST20), and Liangmen (ST21) is higher than that of healthy patients.(11)

    In contrast to the central nervous system activation by sham acupoints, Taichong (LR3), Zhongdu (LR6), Zusanli (ST36) and Xiangu (ST43) had the common effect of activating two specific areas of the brain: the bilateral primary somatosensory area and the ipsilateral cerebellum. Acupuncture stimulation of both acupoints Taichong (LR3) and Zhongdu (LR6) evoked activation at the ipsilateralsuperior parietal lobe (BA7). Acupuncture stimulation of both acupoints Zusanli (ST36) and Xiangu (ST43) evoked activation at the ipsilateral middle frontal gyrus (BA10). These results suggest that different acupoints on the same meridian may activate certain similar areas of the brain.(12)

    Biochemistry
    Ion concentration is special in acupoints and meridians. There is a high concentration of calcium (Ca2+), and potassium ions (K+), and a low concentration of sodium (Na+).(13) Stimulating the acupoints on the meridian could cause the Ca2+ concentration to increase in other points of the same meridian but to reduce in the control points (lateral to the meridian points). The results indicate that Ca2+ maybe involved in the activities of the meridians.(14) When acupoints are needled, the concentrations of K+ and Na+ change contrarily. The increased concentration of K+ is accompanied by decreased Na+, vice versa, indicating acupuncture may strengthen the sodium (potassium) pump. Acupuncture also reduces pH values in the acupoints.(15)
    Vigorous metabolism can be detected in acupoints and meridians. Transcutaneous CO2 emission is an important index for the metabolizing level. CO2 emission is more from acupoints than that from non-acupoints. (16) The distribution of transcutaneous CO2 emission is highly related to the position on the body. Transcutaneous CO2 emission is significantly higher at Daling (PC7) and Quze (PC3) than the control points beside them.(17) Needling acupoints adds to the CO2 emission and oxygen consumption.(18) It has also been discovered that oxygen partial pressure is higher in acupoints than that in non-acupoints. Electro-acupuncture at Hegu (LI4) and Neiguan (PC6) depresses the oxygen partial pressure, and the oxygen partial pressure recovers gradually after removal of electroacupuncture.(19) Mechanical pressure could block the induction of acupuncture treatment on oxygenpartial pressure.(20)

    Current Thought
    All of these studies prove the objective existence of meridians in the human body, and meridians could regulate physical functions. However, any hypothesis has limitations in explaining meridian phenomena and can not truly reflect the internal character of CM. One hypothesis usually illuminates partial meaning. Among these hypotheses, some experimental results are mutually contradictory. Meanwhile, no negative result or counter view regarding the existence of meridians was reported. There were rather, many arguments in documented studies to prove their existence.(21-23) We need to maintain a holistic viewpoint and support innovative ideas.
    Firstly, it is most important that any hypothesis about meridian essence should originate from observation of the human body, as meridian theory was born in medical practice to treat diseases in numerous patients. Animal experiments, therefore, cannot truly reflect meridian phenomena in the human body.
    Secondly, research of meridian essence should begin with the meridians’ physical functions and pathological changes in order to maintain the fundamental nature of meridians.
    Thirdly, the research should be based upon the theory of CM, yet coupled with the integration of modern techniques to further examine the scientific contents of meridians.
    Fourthly, the theoretical research should be done in combination with clinical practice to test the achievements in actual conditions.
    Fifthly, more attention should be given to negative results in studies in order to more accurately discover the real essence of meridians, and thus avoid being blinded by superfluous information. Research of meridian essence is a pivotal aspect of Chinese academia, and continued debate will further drive the development of medical science.

    Acknowledgement
    We gratefully thank the assistance of Michael R. Berger, M.S. Medicine-Acupuncture, Tuina, in revising the manuscript.

    REFERENCES
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    3. Hu XL, Wu BH, LI WF, LI BJ. Preliminary study on plotting out the channel course with skin impedance as index. Acupunct Res (Chin) 1987;(Suppl):9-15,8.
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    5. Wang BX, ed. Abroad studies of meridians. 1st ed. Beijing: People’s Medical Publishing House;1984:29.
    6. Pontarollo F, Rapacioli G, Bellavite P. Increase of electrodermal activity of heart meridian during physical exercise: the significance of electrical values in acupuncture and diagnostic importance. Complement Ther Clin Pract 2010;16:149-153.
    7. Keith S, Kent C. The transport of extremely low-frequency electrical signals through an acupuncture meridian compared to non-meridian tissue. J Altern Complement Med 2011;7:127-132.
    8 Han HJ, Park SJ, Soh KS, Myoung HS, Lee KJ, Ogay V, et al. Electrical characterization of proposed transpositional acupoints on the urinary bladder meridian in a rat model. Evid Based Complement Alternat Med 2011;295475
    9. Yan ZQ, Chi YR, Zhu XR, Cheng J, Wang PJ. Applications of surface ultra-weak luminescence law in the study of Chinese medicine syndromes, needling sensation and acupoints characteristics. Beijing J Tradit Chin Med (Chin) 1993;12:51-53.
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    14. Guo Y, Xu TP, Chen JS, Zhang CX, Jiang P. Experimental study of the acupuncture effects on calcium ion concentration in rabbits’ acupoints. World J Acupunct Moxibust 1992;2:51-55.
    15. Jiang HZ, Wang Q, Zhang MM, Gong P, Huang GY. Effect of acupuncture on pH values of acupoints in the goat. Chin Acupunct Moxibust (Chin) 2006;26:732-734.
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  12. This was fascinating and very helpful. I will refer my skeptical relatives here next time I get acupuncture! Thank you.

  13. I had a stroke 7 years ago at the age of 21. A year later it seemed like I had made an almost complete recovery. I have since then had three children and struggle daily with chronic fatigue. We have tried everthing we can to determine the root cause and have come to the conclusion that it must be a result of the stroke. Do you think acupuncture could be helpful to treat post-stroke fatigue?

  14. Chris, I follow all your health podcasts, etc. And love it all. As an acupuncturist, I LOVED this explanation. I have used the “micro-trauma” explanation, but not to this depth. Thanks!!!!

  15. Thanks for your article! I’ve suffered PCOS, Hypothyroidism and Adrenal Fatigue for the past year, and what cured me are moderate exercise, processed- and gluten-free diet, natural supplements and ACUPUNCTURE! It was like the needed “key” for me to get better, faster.

    I swear by it and I could never forget that chance encounter with the Korean acupuncturist in our town. 🙂

  16. Nice series. I am currently searching for an accupuncture practitioner and am wondering if accupuncture will still work if the practitioner is all into “energy meridians” instead of concerned with physiology?

  17. Also, you cannot cure blood deficiency by adding more blood, or qi deficiency by adding oxygen, or Jing deficiency by adding harmones. Western medicine has tried that and it does not work, and their patients are made to take the pills continuously and endure the side effects and further imbalance the drugs cause.

    The body must return to balance itself, through the persuasion methods utilized in Chinese medicine and similar intuitive practices. The lack of a substance is not the concern, but is the symptom. The imbalance is the concern, and this has to do with yin and yang, which are unidentifiable, relative terms and are the chief target of the Chinese doctor’s medical inquiry. Once western medicine identified vitamins, they assumed they could extract them and use them by themselves to nourish a patient, as they did when they discovered fat, carbohydrates, and protein as the primary constituents of food. They were wrong, and discovered there was a unique balance of various substances within each food, an yin yang balance that allowed that food to live and grow. They still do not understand this balance, just as they do not understand the balance within the body, believing you can separate it into parts to be addressed individually. This is their folly, which was not made the basis of Chinese medicine thousands of years ago, when they developed a medicine based on universal principles understood by wise men who lived healthy lives (not scientists unconcerned with understanding the true nature of the universe in totality, but wished to examine its parts).

    Chinese medicine cannot be influenced by western science if it is to preserve its true meaning and influence western thought. If it is, the true meaning will be discarded to make room for scientific, fragmented understanding, and we will have taken a mighty step backwards in our ability to understand the larger processes in the universe.

  18. Thanks for the fantastic article series! Concerning the significance of such translational science, while it works to bridge the gap with western science a little, it still ignores the classical cultural perspective. For instance, oxygen and harmones are easily dismissed as simply chemicals in modern thinking, but qi and jing are very precious in classical china with even severe moral concerns associated with them. It’s like you lose respect for something when you stare at it and label it dismissively, considering yourself/your culture to have “conquered its mystery”.  You are “above” it instead of “of” it. This is why I don’t believe they’re accurate translations, because they don’t translate the cultural significance of the concepts. There’s also a concern I have that the classical understanding has a subjectivity that is important to understanding the concepts clinically, which can be lost with excessive objectivity.

  19. Greetings,
    I’m a Licensed Massage Therapist, & Shiatsu Practitioner. I have a true love for Chinese medicine. Thanks so much for bridging the paradigm gap between East and West. Much appreciated! I would like very much for my circle of contacts to be better aware of this information. Mind if I quote you on some items? I’ll give a link to your site and due credit. I’m seriously considering becoming an acupuncturist. Thanks for taking some of the mystery out of the Art of Chinese medicine. Here is a sample of my newsletter. Feel free to subscribe if you like. Thanks again! Pamela
    http://conta.cc/pEPwIb via #constantcontact