What are Acupuncture Meridians?

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Recent approaches on signal transduction and transmission in acupuncture: a biophysical overview for medical sciencesIt is the main objective of this review to provide a survey of the main theories and explanatory approaches to the signal transduction and conduction in acupuncture and to describe them in in terms of their explanatory hypotheses, limitations and weaknesses. The most of the literature found supports theories for neural conduction, including gate control.

Anatomical Evidence of Acupuncture Meridians in the Human Extracellular Matrix: Results from a Macroscopic and Microscopic Interdisciplinary Multicentre Study on Human Corpses"Our study found evidence that acupuncture meridians were part of the human extracellular matrix and that fascia was an important part of the anatomic substrate of acupuncture meridians. At the same time, we found vessel-nerve-bundles, which were hypothesized to account for 80% of acupuncture points, only in a few acupuncture points. Therefore, our findings contradict the theory that acupuncture points are only located along the nervous channels." 

It would be very interesting if the authors had considered the relationship between the newly discovered interstitium and oscillating EM signals. The interstitium consists mostly of water and it includes fascia. With more sophisticated in vivo measuring capabilities, acupuncture meridians and acupuncture could potentially be found to be related to the interstitium.

Neuroembryology of the Acupuncture Principal Meridians: Part 3. The Head and Neck. Accumulating evidence from anatomical, physiologic, and neuroimaging research shows that Classical acupuncture points stimulate nerve trunks or their branches in the head, trunk, and extremities. The first part of this series revealed that phenomenon in the extremities. Principal meridian distributions mirror those of major peripheral nerves there and Classical acupuncture points are proximate to peripheral nerves there. Overall, the acupuncture Principal meridians can be conceptualized to have a neuroanatomical substrate that is corroborated by developmental neuroembryology. Note that one of the authors is from the Mayo Clinic.

Peripheral Sensory Nerve Tissue but Not Connective Tissue Is Involved in the Action of Acupuncture. The findings suggest that nerve tissue, but not connective tissue, is responsible for generating the effects of acupuncture.

Is the newly described interstitial network the anatomical basis of acupuncture meridians? A commentary. We consider the peculiarities of the interstitium to be the morphological basis of at least some of the known phenomena along acupuncture meridians.

Effect of Auricular Acupuncture on Propofol Induction Dose: Could Vagus Nerve and Parasympathetic Stimulation Replace Intravenous Co-Induction Agents? Auricular acupuncture is a method for stimulating the vagus nerve and parasympathetic nervous system. Preoperative auricular acupuncture enabled reductions of drugs for general anesthesia without any clinically important side-effects.

Acupuncture Mechanisms: Anesthesia, Analgesia and Protection on Organ Functions. This review summarizes research progress on the mechanisms of acupuncture for analgesia; its protection against organ function injury in anesthesia; and its effect on analgesia, immunomodulation, neuroendocrine regulation and multiple organ protection. The current evidence supports that acupuncture analgesia and its organ protection in anesthesia is associated with the integration of neuroendocrine-immune networks at the level of neurotransmitters, cytokines, hormones, neuronal ensembles, lymphocytes, and endocrine cells. Although the mechanisms of acupuncture analgesia and its organ protection are still not completely understood, basic as well as clinic research on the mechanisms and applications of acupuncture and related techniques are being carried out.

Acupuncture For Military PTSD Found Effective. Acupuncture effectively treats posttraumatic stress disorder (PTSD). Researchers conducting a randomized controlled study of active duty US military service personnel concludes that acupuncture significantly improves patient outcomes for PTSD patients. Acupuncture also induced secondary improvements: reduced depression and pain, improved mental and physical health functioning.

Low frequency (electroacupuncture) or manual acupuncture stimulates nerve fibers thus affecting large numbers of neurotransmitter systems in the brain and spinal cord, such as acetylcholine, opioids, and serotonin. Acupuncture sensitive neurons have been identified in the brain. Acupuncture has been shown to affect signalling molecules in many animal model studies. Research has found that acupoints have increased conductance, decreased resistance/impedance, elevated capacitance, and higher potential compared to controls. Yet there is still a lack of research results which adequately explain the physiological basis of meridians and the 'qi' that moves along them. Although qi and the flow of it through meridians has not been directly measured, bioenergy can be measured. Using electromyography, researchers have shown that electric energy caused by acupuncture does in fact travel along pathways roughly corresponding to meridians. This energy follows blood flow that was initiated and stimulated by acupuncture. For more information on the use of electromyographyEEGPhoton Migration SpectroscopyLaser Doppler Flometry, and Gas Discharge Visualization to study Acupuncture, Qigong, andTtai Chi see Publications on the Laboratory for Mind-Body Signaling & Energy Research website.

Acupuncture benefits breast cancer survivors.

Researchers at Penn Medicine and other institutions found that electro-acupuncture (“real” acupuncture) helped reduce joint pain by as much as 40 percent in women with breast cancer, whether the patient expected it to work or not. The study also found that “sham” acupuncture – which involves nonpenetrative needles and no electrical stimulation – provided pain reduction as high as 80 percent if patients had a high degree of expectation that it would work. The study results provide important implications for future treatment of breast cancer patients with joint pain. Patients who reported pain relief had increased expectancy that it would continue to work over the course of their acupuncture treatment as compared with nonresponders, suggesting that positive responses during the process of real acupuncture increased the expectations of further positive outcomes. “These findings certainly challenge the notion held by some that acupuncture is ‘all placebo,’” said the study’s lead author Joshua Bauml, MD, an assistant professor of Medicine in the Abramson Cancer Center. “If it were ‘all placebo,’ patients receiving real acupuncture who had low expectations that it would work would report little or no reductions in pain. But that’s not the case.” Sham acupuncture only produced clinically important pain reduction for those with high onset expectancy. But patients with the highest expectation that it would work reported as much as 80 percent reductions in pain – twice the rate of patients receiving real acupuncture. Sham acupuncture patients with low baseline expectancy scores did not report any significant pain reduction.

NCCIH Acupuncture CEUs

The National Center for Complementary and Integrative Health (NCCIH) continues to expand its online continuing medical education (CME) offerings. CEUs are available from NCCIH for these lectures. 

International Perspectives on Acupuncture Research. Claudia M. Witt, M.D., M.B.A., a professor for medicine and Acting Director of the Institute for Social Medicine, Epidemiology and Health Economics at the University Medical Center Charité in Berlin, Germany. Dr. Witt is also visiting professor at the University of Maryland School of Medicine. This talk includes the safety of acupuncture, it's efficacy and effectiveness, neuroimaging and stimulation studies, acupuncture styles, individual treatment response, comparative effectiveness research, and more. 

Neurobiological Correlates of Acupuncture. Bruce Rosen is Professor of Radiology at Harvard Medical School (HMS) and Director of the Martinos Center for Biomedical Imaging at Massachusetts General Hospital (MGH). Dr. Rosen's research focuses on the development and utilization of physiological and functional nuclear magnetic resonance (NMR) techniques and the application of this technology to solve specific biological and clinical problems. 

NCCIH Information on Acupuncture 

Acupuncture Academic Research

American Academy of Medical Acupuncture.

The Society for Acupuncture Research. The society's mission is to promote, advance and disseminate scientific inquiry into Oriental medicine systems, which include acupuncture, herbal therapy and other modalities through quantitative and qualitative research addressing clinical efficacy, physiological mechanisms, patterns of use and theoretical foundations.

Acupuncture for Pets

Acupuncture now healing pets


Acupuncture helps sick wise owls fly wild again in Spain. Most orthodox medical doctors tend to dismiss the idea that acupuncture can help living beings, be they animals or humans. Yet veterinary acupuncture is not all that unusual, and has been used for years to treat pain in horses, with results so positive even orthodox vets have had to acknowledge the benefits. The International Veterinary Acupuncture Society says the use of the ancient Chinese therapy using super thin needles to stimulate specific energy points in the body is growing worldwide. A Spanish vet has found it useful even for owls.

The Personal Energy Centre & The Global Qi Project

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A NEW BOOK 'The Adventures of an Acupuncturer -- A Clinical Autobiography of Qigong Acupuncture’ is now available free, by simply clicking on the link in the brown box on the home page of The Personal Energy Centre Global Qi Project website.

Energy is the basis of Life. The better your energy, the better your life. The more energy, the more life. Energy underlies your health, and state of being. This has been understood for 2,000+ years in China where it is called Qigong or Chi Kung – described and presented here. So, to find out how to develop and increase your energy, health & life read on…

THE PERSONAL ENERGY CENTRE is the name of the new practice in Liverpool, England, presenting Qigong, Acupuncture and Tao Studies. 

THE GLOBAL QI PROJECT was initiated in 2008, to make the book and programme on Eight Extraordinary Meridians Qigong available to whoever would find it of interest, and more information is provided beneath.

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Unanticipated Insights into Biomedicine from the Study of Acupuncture. Research into acupuncture has had ripple effects beyond the field of acupuncture. This paper identifies five exemplars to illustrate that there is tangible evidence of the way insights gleaned from acupuncture research have informed biomedical research, practice, or policy. The first exemplar documents how early research into acupuncture analgesia has expanded into neuroimaging research, broadening physiologic understanding and treatment of chronic pain. The second describes how the acupuncture needle has become a tool to enhance biomedical knowledge of connective tissue. The third exemplar, which illustrates use of a modified acupuncture needle as a sham device, focuses on emergent understanding of placebo effects and, in turn, on insights into therapeutic encounters in treatments unrelated to acupuncture. The fourth exemplar documents that two medical devices now in widespread use were inspired by acupuncture: transcutaneous electrical nerve stimulators for pain control and antinausea wrist bands. The final exemplar describes how pragmatic clinical trial designs applied in acupuncture research have informed current general interest in comparative effectiveness research.

pubmed logo Acupuncture for Chronic Low Back Pain: Recommendations to Medicare/Medicaid from the Society for Acupuncture Research (SAR). This is SARs response to the U.S. government’s Center for Medicare and Medicaid Services call for public comment related to the government’s exploration of inclusion of acupuncture and licensed acupuncturists in federal payment schemes. It includes information on the biological mechanisms of acupuncture and clinical evidence that acupuncture is safe, effective, and cost-effective for chronic pain. Journal of Alternative and Complementary Medicine. Vol 25. No 4. 2019.

National Center for Complementary and Integrative Health (NCCIH)

New Findings Suggest Acupuncture Stimulation Reduces Systemic Inflammation. New findings published in a recent issue of the journal Neuron suggest that acupuncture stimulation reduces systemic inflammation in intensity-, somatotopy-, and disease state-dependent manners. The research, supported by the National Center for Complementary and Integrative Health (NCCIH), also suggests that electroacupuncture has an advantage over manual acupuncture in that the intensity of electroacupuncture is easier to control. NCCIH is a component of the National Institutes of Health (NIH).

Acupuncture: What You Need To Know

How much do we know about acupuncture? What do we know about the effectiveness of acupuncture? What do we know about the safety of acupuncture? What Is Acupuncture? What the Science Says About the Effectiveness of Acupuncture.

NCCIH - How the Body and Brain Achieve Carpal Tunnel Pain Relief via Acupuncture

"New research describes how acupuncture may achieve local pain-relieving effects in people with carpal tunnel syndrome (CTS) while also showing effects of the technique in the brain’s pain centers. The study, funded in part by the National Center for Complementary and Integrative Health and conducted by a multicenter team of scientists at Massachusetts General Hospital, Logan University, the Korean Institute of Oriental Medicine, Spaulding Rehabilitation Hospital, Harvard Vanguard Medical Associates/Atrium Health, and Beth Israel Deaconess Medical Center, is the first sham-controlled neuroimaging acupuncture study for CTS. It was published in the journal Brain." Full article.

PDQ Cancer Info coverPDQ Cancer Information Summary for Acupuncture - Health Professional Version.

PDQ Cancer Information Summary for Acupuncture - Patient Version. The PDQ cancer information summaries are peer-reviewed, evidence-based summaries on topics including adult and pediatric cancer treatment, supportive and palliative care, screening, prevention, genetics, and complementary and alternative medicine. There are versions for patients and professionals. The summaries come from the National Cancer Institute's comprehensive cancer database, PDQ (Physician Data Query). This PDQ cancer information summary has current information about the use of acupuncture in the treatment of people with cancer. It is meant to inform and help patients, families, and caregivers. It does not give formal guidelines or recommendations for making decisions about health care. Editorial Boards write the PDQ cancer information summaries and keep them up to date. These Boards are made up of experts in cancer treatment and other specialties related to cancer. The summaries are reviewed regularly and changes are made when there is new information. The date on each summary ("Date Last Modified") is the date of the most recent change. The information in this patient summary was taken from the health professional version, which is reviewed regularly and updated as needed, by the PDQ Cancer Complementary and Alternative Medicine Editorial Board.

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Acupuncture for chronic pain

Over the years there has been substantial debate about whether acupuncture really works for chronic pain. Research from an international team of experts adds to the evidence that it does provide real relief from common forms of pain. The team pooled the results of 29 studies involving nearly 18,000 participants. Some had acupuncture, some had “sham” acupuncture, and some didn’t have acupuncture at all. Overall, acupuncture relieved pain by about 50%. More.


Harvard Medical School review presents the latest available evidence regarding the use of acupuncture for cancer pain. Cancer pain is one of most prevalent symptoms in patients with cancer. The National Comprehensive Cancer Network guidelines for adult cancer pain recommends acupuncture, as one of several integrative interventions, in conjunction with pharmacologic intervention as needed. It also provides "actionable" acupuncture protocols for specific cancer pain conditions and related symptoms in order to provide more clinically relevant solutions for clinicians and cancer patients with pain. These conditions include postoperative cancer pain, postoperative nausea and vomiting, postsurgical gastroparesis syndrome, opioid-induced constipation, opioid-induced pruritus, chemotherapy-induced neuropathy, aromatase inhibitor-associated joint pain, and neck dissection-related pain and dysfunction.

In 1997, the National Institutes of Health issued a Consensus Statement which officially approved acupuncture for use in medical treatment.

 NIH Consensus Statement Online 1997 Nov 3-5; month, day]; 15(5):1-34.

Acupuncture for Chronic Pain


CLINICAL QUESTION: Is acupuncture associated with reduced pain outcomes for patients with chronic pain compared with sham-acupuncture (placebo) or no-acupuncture control?

BOTTOM LINE: Acupuncture is associated with improved pain outcomes compared with sham-acupuncture and no-acupuncture control, with response rates of approximately 30% for no acupuncture, 42.5% for sham acupuncture, and 50% for acupuncture.

Journal of the American Medical Association. 2014 Mar 5;311(9):955-6. doi: 10.1001/jama.2013.285478. Vickers AJ1, Linde K2.1Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, New York. 2Technical University, Munich, Germany. PMID: 24595780 : PMC4036643 [Available on 2015/3/5]

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Summary of Acupuncture: Review and Analysis of Reports on Controlled Clinical Trials.


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Gathering Data Points for Acupuncture Research

In the field of complementary and integrative health, few topics have generated more controversy than acupuncture. This is driven by an ongoing discordance at the core of this ancient therapy: although a growing body of evidence demonstrates acupuncture’s potential role in managing different conditions, like chronic pain or insomnia, the practice itself isn’t well understood. In particular, critics of acupuncture research have repeatedly pointed out that “acupoints,” one of the fundamental tenets of acupuncture, aren’t based on an objective understanding of the body. 

The National Center for Complementary and Integrative Health (NCCIH) has put into motion an effort to address this problem with a new initiative that will result in the development of an open-access repository and database for the anatomical and physiological correlates of acupoints. This data initiative has long been needed to advance the work of researchers in the field. Director’s Page, Helene M. Langevin, M.D. June 14, 2023

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Default Mode Network as a Neural Substrate of Acupuncture: Evidence, Challenges and Strategy

Activities of brain regions in the default mode network (DMN) are modulated by acupuncture. DMN is crucial for maintaining physiological homeostasis and its functional architecture becomes disrupted in various disorders. More.

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Selected Peer-Reviewed Acupuncture Research

A neuroanatomical basis for electroacupuncture to drive the vagal–adrenal axis.

Systematic Review: Acupuncture vs Standard Pharmacological Therapy for Migraine Prevention. Harvard and Stanford researchers: "There is growing evidence that acupuncture is just as effective and has fewer side effects than many of the standard pharmaceutical agents that are currently used."

Signal Transduction Pathways of Acupuncture for Treating Some Nervous System DiseasesAcupuncture affects synaptic plasticity, causes an increase in neurotrophic factors, and results in neuroprotection, cell proliferation, antiapoptosis, antioxidant activity, anti-inflammation, and maintenance of the blood-brain barrier.

Acupuncture for Chronic Pain: Update of an Individual Patient Data Meta-Analysis. The authors conclude: "Acupuncture is effective for the treatment of chronic musculoskeletal, headache and osteoarthritis pain. Treatment effects of acupuncture persist over time and cannot be explained solely in terms of placebo effects. Referral for a course of acupuncture treatment is a reasonable option for a patient with chronic pain."

Acupuncture for Treatment of Persistent Disturbed Sleep: A Randomized Clinical Trial in Veterans With Mild Traumatic Brain Injury and Posttraumatic Stress Disorder. Real acupuncture, compared with a sham needling procedure, resulted in a significant improvement in sleep measures for veterans with mTBI and disturbed sleep, even in the presence of PTSD. These results indicate that an alternative-medicine treatment modality like acupuncture can provide clinically significant relief for a particularly recalcitrant problem affecting large segments of the veteran population.

Japanese researchers show that electroacupuncture can decrease blood pressure and heart rate.

Characterizing acupuncture stimuli using brain imaging with FMRI - a systematic review and meta-analysis of the literature. Brain response to acupuncture stimuli encompasses a broad network of regions consistent with not just somatosensory, but also affective and cognitive processing. Acupuncture can modulate the activity within specific brain areas. Media Article and Image: Where acupuncture pricks the brain.

Pain and sensory detection threshold response to acupuncture is modulated by coping strategy and acupuncture sensation. The interaction between psychological coping strategy and acupuncture sensation intensity can differentially modulate pain and sensory detection threshold response to EA. In a clinical context, our findings suggest that instructions given to the patient can significantly affect therapeutic outcomes and the relationship between acupuncture intensity and clinical response. Specifically, acupuncture analgesia can be enhanced by matching physical stimulation intensity with psychological coping strategy to acupuncture contexts.

Acupuncture affects skin blood flow and muscle blood volume.

Acupoints Initiate the Healing Process. Needling is the first step of traditional acupuncture therapy. Needling reactions- neuronal, biophysical, and biochemical-are the beginning of healing. The messengers of the three reactions involved may include neurotransmitters, cytokines, hormones, and inflammatory factors. Healing may be potentiated through these messengers in neuronal and humoral pathways. The reactions manifest as erythema and De Qi-both of which are common phenomena used as positive signs in acupuncture treatment.

Systematic review finds acupuncture is helpful in managing symptoms in cancer patients. Acupuncture should be considered for symptom management where there are limited treatment options, using current peer-reviewed guidelines and clinical reasoning.

AcuTrials®: an online database of randomized controlled trials and systematic reviews of acupuncture. The AcuTrials® Database is a comprehensive collection of randomized controlled trials and systematic reviews of acupuncture published in the English language. The database is maintained by the Research Department at Oregon College of Oriental Medicine (OCOM) and is compiled primarily from PubMed, the Cochrane Library and the OCOM library. AcuTrials® is a resource for practitioners, students, and researchers interested in refining searches for specific acupuncture research. Database:

Proposed catalog of the neuroanatomy and the stratified anatomy for the 361 acupuncture points of 14 channels. In spite of the extensive research on acupuncture mechanisms, no comprehensive and systematic peer-reviewed reference list of the stratified anatomical and the neuroanatomical features of all 361 acupuncture points exists. This study creates a reference list of the neuroanatomy and the stratified anatomy for each of the 361 acupuncture points on the 14 classical channels and for 34 extra points. This is a step towards western medical standardization of acupuncture points.

Chinese researchers find that acupuncture relieves clinical pain by modulating the brain's default mode network.

Connectomics: A New Direction in Research to Understand the Mechanism of Acupuncture. This paper gives an overview of the application of connectomics in acupuncture research, with special emphasis on present findings of acupuncture and its influence on cerebral functional connectivity.

Evidence Map of Acupuncture. The Department of Veterans Affairs, Health Services Research & Development Service Evidence-based Synthesis Program was established to provide timely and accurate syntheses of targeted healthcare topics of particular importance to VA managers and policymakers, as they work to improve the health and healthcare of Veterans. The ESP disseminates these reports throughout VA. This report provides in-depth information on acupuncture derived from systematic reviews.

Acupuncture modulates the functional connectivity of the default mode network in stroke patients.

Acupuncture, Connective Tissue, and Peripheral Sensory Modulation. Although considerable controversy surrounds the legitimacy of acupuncture as a treatment, a growing literature on the physiological effects of acupuncture needling in animals and humans is providing new insights into basic cellular mechanisms including connective tissue mechanotransduction and purinergic signaling. This review summarizes these findings and proposes a model combining connective tissue plasticity and peripheral sensory modulation in response to the sustained stretching of tissue that results from acupuncture needle manipulation.

Electrical properties of acupuncture points and meridians: a systematic review. Twenty-four articles from twenty-nine studies in publications from 1970 to 2007 were searched to support or refute the claim that acupuncture points or meridians possess distinct electrical properties. The reported electrical associations at acupuncture points include increased conductance, decreased resistance/impedance, elevated capacitance, and higher potential compared to controls.

New findings of the correlation between acupoints and corresponding brain cortices using functional MRI. The results obtained demonstrate the correlation between activation of specific areas of brain cortices and corresponding acupoint stimulation predicted by ancient acupuncture literature.

Analgesic acupuncture effects outlast the needling period. Pain-associated brain areas were modulated in direct response to a preceding acupuncture treatment.

Traditional acupuncture triggers a local increase in adenosine in human subjects.There is increasing evidence that local chemical production of adenosine via connective tissue wrapping around needles is one factor that contributes to the pain relieving mechanism of acupuncture in human subjects.

Neurobiological mechanisms of acupuncture analgesia. Acupuncture has been proven by biochemical, immunohistochemical, molecular biological and neurophysiological investigations. It has been shown that short term acupuncture analgesia is mediated by an activation of endogenous antinociceptive systems and descending inhibitory systems. Long term effects cannot be explained sufficiently by experimental results; however, they suggest an involvement of long term inhibitory synaptic modification at spinal cord neurons and clinical and radiological findings indicate limbic system modulation.

Amazing acupuncture: So many benefits of getting needled. The World Health Organization says acupuncture may help ease digestive problems like constipation and diarrhea, chronic sinus and lung infections, all sorts of pain from headaches and migraines to back pain and osteoarthritis, infertility, and even urinary and menstrual problems.

15TH World Congress on Qigong and Traditional Chinese Medicine Research Symposium (2013)

Dr. John Longhurst, M.D. Ph.D. Director of the Susan Samueli Center for Integrative Medicine and Professor in the Departments of Medicine, Physiology & Biophysics and Pharmacology at UC Irvine.

  • There is not much difference between manual and electro-acupuncture (EA). EA is a little stronger and more precise. 
  • Pain threshold can go up with acupuncture and this effect can be blocked with drugs, proving the physiological effects of acupuncture.
  • 70% of experimental subjects are responsive to acupuncture. The 30% who are not responsive are affected by CCK, particularly its octapeptide CCK8, which inhibits the action of opiods in the central nervous system. 
  • Manual stimulation of nerve fibers leads to local chemical production, and this may be responsible for catalyzing remote acupuncture effects. Electroacupuncture has some effect upon hypertension, even four weeks after treatment. Acupuncture points physically migrate, but the effect of needling the moving point stays the same. 
  • Acupuncture Mechanisms: low frequency or manual acupuncture stimulates nerve fibers thus affecting many neuotransmitter systems in the brain and spinal cord, such as the opiod system. Excitatory neurotransmitters include acetylcholine. Example inhibitory neurotransmitters include opioids and serotonin. Acupuncture responsive neurons in the brain can be identified. 
  • The World Health Organization diseases and symptoms for which acupuncture is proven effective include pain, depression, nausea and vomiting, blood pressure abnormalities, and stroke.