Western Medicine perspective

Broadly speaking, acupuncture has three primary effects:

  1. It relieves pain.
  2. It reduces inflammation.
  3. It restores homeostasis.

Homeostasis refers to the body’s ability to regulate its environment and maintain internal balance. All diseases involve a disturbance of homeostasis, and nearly all diseases involve some degree of pain and inflammation. In fact, research over the last several decades suggests that many serious conditions like heart disease previously thought to have other causes are in fact primarily caused by chronic inflammation. If we understand that most diseases are characterized by pain, inflammation and disturbance of homeostasis, we begin to understand why acupuncture can be effective for so many conditions.

Several modes of action have been identified for acupuncture, which I’ll discuss below. The mechanisms can get quite complex. But ultimately acupuncture is a remarkably simple technique that depends entirely upon one thing: the stimulation of the peripheral nervous system. It’s important to point out that when nerves supplying acupoints are cut or blocked there is no acupuncture effect.

A large body of evidence indicates that acupoints, or “superficial nodes” as they are more accurately translated, have abundant supply of nerves. According to Chen Shaozong, “For 95% of all points in the range of 1.0 cm around a point, there exist nerve trunks or rather large nerve branches.” 1

The following is a list of mechanisms that have been identified so far:

  • Acupuncture promotes blood flow. This is significant because everything the body needs to heal is in the blood, including oxygen, nutrients we absorb from food, immune substances, hormones, analgesics (painkillers) and anti-inflammatories. Restoring proper blood flow is vital to promoting and maintaining health. For example if blood flow is diminished by as little as 3% in the breast area cancer may develop. Blood flow decreases as we age and can be impacted by trauma, injuries and certain diseases. Acupuncture has been shown to increase blood flow and vasodilation in several regions of the body.
  • Acupuncture promotes local healing Acupuncture stimulates nerve fibres in the skin. Stimulating these nerves sets off an action potential which spreads locally, causing the local blood vessels to dilate and increasing blood flow. This blood flow also increases at a deeper level, encouraging tissue healing. Acupuncture also creates “micro traumas” that stimulate the body’s ability to spontaneously heal injuries to the tissue through nervous, immune and endocrine system activation. As the body heals the micro traumas induced by acupuncture, it also heals any surrounding tissue damage left over from old injuries.
  • Acupuncture releases natural painkillers. The action potential can also travel up the nerve directly to it’s particular segment in the spinal cord where it depressed the activity of the dorsal horn, reducing it’s response to painful stimuli. Acupuncture inhibits pain from any part of the body which sends nerves to that particular segment of the spinal cord.
  • Acupuncture reduces pain throughout the body. These same action potentials produced by the acupuncture needle then travel on from the dorsal horn up to the brain stem. Here, they stimulate the body’s own pain suppressing mechanisms. The descending nerves release some neurotransmitters at every segment of the spinal cord. Acupuncture can activate the extra segmental effect, and so have effects that extend to the whole body, well beyond the segment in which acupuncture is applied. Inserting a needle sends a signal through the nervous system to the brain, where chemicals such as endorphins, norepinephrine and enkephalin are released. Some of these substances are 10-200 times more potent than morphine!
  • Acupuncture reduces both the intensity and perception of chronic pain. It does this through a process called “descending control normalization”, which involves the serotonergic nervous system.
  • Acupuncture relaxes shortened muscles. This in turn releases pressure on joint structures and nerves, and promotes blood flow.
  • Acupuncture has a calming effect and can regulate hormones. This is perhaps the most important systemic effect of acupuncture. After reaching the midbrain, the action potential influences other structures in the brain, including the cerebral cortex, hypothalamus and limbic system. This is where acupuncture can regulate these structures and can induce calm and improving wellbeing. Recent research suggests that acupuncture stimulates the release of oxytocin, a hormone and signaling substance that regulates the parasympathetic nervous system. You’ve probably heard of the “fight-or-flight” response that is governed by the sympathetic nervous system. The parasympathetic nervous system has been called the “rest-and-digest” or “calm-and-connect” system, and in many ways is the opposite of the sympathetic system. Recent research has implicated impaired parasympathetic function in a wide range of autoimmune diseases, including arthritis, lupus, rheumatoid arthritis and inflammatory bowel disease.
  •  There is alsp good evidence that acupuncture can alter autonomic activity at the level of the hypothalamus influencing stimulation of the anterior pituitary gland with evidence that acupuncture stimulates the release of both β endorphin and Adrenocorticotropic hormone (ACTH). Gonadotrophin ( GnRH) produced at the arcuate nucleus of the hypothalamus may also have clinical effect including alteration in the regulation of menstrual timing, flow and reduction of dysmenorrhoea ( painful menstruation).
  • Post menopausal hot flushes are due to dysfunction of temperature regulatory centre. There is some evidence to suggest the release of β endorphin tends to reduce the frequency of hot flushes, by the release of serotonin. Multi centred studies are underway in Melbourne presently to further the evidence of this. Many studies have also supported the use of acupuncture to improve fertility and again multi centred studies are in progress presently.