Acupuncture, How Does it Work?
I have been asked this fascinating question countless times! There is still much left to learn about acupuncture mechanisms and the human body. Scientific advances in neuroscience and anatomy have enabled the development of several theories receiving interest from the scientific community.
This article attemps to summarise the main physiological explanations considered to explain how acupuncture works. It is based on the synthesis work by K.J. Cheng, I. Lund and T. Lunderberg.
Neurobiological Mechanisms of Acupuncture
for Some Common Illnesses, by Dr. Cheng (2013)
Mechanisms of Acupuncture,
by Lund and Lunderberg (2016)
Main Action Mechanisms Underlying Acupuncture
1. Local Effect of Acupuncture on Body Tissues
By inserting a needle into the skin and underlying tissues, the acupuncturist induces micro-lesions, causing a local blood flow, tissue regeneration, and analgesia. The acupuncture needle will stimulate the action of adjacent nerves and cause the release of neuropeptides, signaling for local vasodilation and increased circulation in the area. This mechanism of action may partly explain the benefits of acupuncture in the treatment of musculoskeletal problems and pain.
2. The Role of Somato-Autonomous Reflexes in Acupuncture
Acupuncture probably has an effect on the body’s homeostasis via the nervous system, by activating somato-autonomous reflexes. This homeostasis of the body involving the sympathetic and para-sympathetic branches of the autonomic nervous system is frequently considered a scientific basis for the concept of the balance between the Yin and Yang of the body, fundamental concepts of Chinese medicine. Several animal studies have demonstrated the activation by acupuncture of these neural pathways (Cheng, 2013).
Research suggests that acupuncture points on the abdomen can induce a reaction on internal organs innervated by the same spinal segment. There is also research on the impact of certain points on the extremities of the body and their action on visceral activities (Cheng, 2013). For example, a study has demonstrated in animals the action of a point on the leg affecting gastric motility, via the activation of the somato-parasympatic reflex of the vagus nerve (Sato, 1997).
3. The Role of Neurotransmitters in Acupuncture
The secretion of neurotransmitters, such as endorphin, by stimulation of the needle in acupuncture is now well established. Acupuncture can also affect the level of other neurotransmitters such as serotonin and dopamine in the limbic system of the brain. This group of brain structures includes the hippocampus, the amygdala and their connections to the hypothalamus, as well as various centers related to emotional behavior, motivation and appetite. This could partly explain the effect of acupuncture to treat depression or help in case of smoking cessation, for example (Cheng, 2013).
4. The Role of Purinergic Signaling in Acupuncture
The acupuncture needle, when inserted into the skin, causes purinergic signaling, namely the secretion of extracellular ATP (adenosine triphosphate) (Burnstock, 2009). Extracellular ATP can cause a cascade of biochemical reactions in tissues and the body. These ATP molecules interact with nerve cells, which send a signal to the spinal cord and the brain. These signals, when directed to the brainstem, seem to play a role in the regulation of various physiological functions, such as digestive, or cardiovascular. When directed to the upper centers of the brain, they can modulate pain.
Acupuncture is often criticized on these claims of being able to treat a large number of health conditions. However, this purinergic signaling phenomenon makes biologically plausible the action of acupuncture on a large number of health conditions (Burstock, 2009).
Watch a conference on this topic: Biochemistry of Acupuncture: A proposal for the Central role of purines, by Mel Hopper Koppelmann, Acupuncturist and M.Sc. Functional Medecine, Director of Evidence Based Acupuncture
5. The Role of Fascia in Acupuncture
Researchers and observers have noticed the correspondence between the fascial planes of the body and the paths of the meridians described in traditional Chinese medicine. Langevin and Yandow (2002) observed an 80% correspondence between the fascia cleavage planes and the path of the meridians. They hypothesize that the fascia acts as a system of self-monitoring in the body, a mechanism still undocumented by science (Cheng, 2013).
Fascia is a connective tissue forming a network in the body and whose properties continue to be discovered. Fascia is piezoelectric, which means it can generate an electric current under mechanical stress. It is interesting to note here that by inserting and turning a needle into the skin and the underlying fascia, the acupuncturist applies mechanical stress to the fascia.
References for this page:
- Burnstock, G.. (2009). Acupuncture: a novel hypothesis for the involvement of purinergic signalling. Medical Hypotheses. Available online.
- Cheng. K (2013) Neurobiological mechanisms of acupuncture for some common illnesses: a clinician’s perspective. Journal of Acupuncture and Meridian Studies. 2014 Jun;7(3):105-14. doi: 10.1016/j.jams.2013.07.008. Epub 2013 Aug 17.
- Lund et Lundeberg (2016) Mechanisms of Acupuncture, Acupuncture and related therapies, Available online.
- Langevin HM, Yandow JA (2002). Relationship of acupuncture points and meridians to connective tissue planes. Anatomical Record. 2002 Dec 15;269(6):257-65. Available online
- Sato A (1997). Neural mechanisms of autonomic responses elicited by somatic sensory stimulation. Neuroscience and Behavioral Physiology, Vol. 27, No. 5, 1997