In traditional Chinese medicine, physical illness and disorders are believed to be caused by imbalances or blockages in a life force called Qi, which flows through the body along meridians, or channels. By stimulating appropriate points along these meridians, the energy is released and regulated, and health is restored.
Western scientists are working to understand how insertion of needles at certain points creates the remarkable changes that have been documented. It has been difficult to do double-blind studies of acupuncture, because unlike with drug trials using placebo medications, “sham” acupuncture points are hard to accomplish. Anytime a needle is inserted into a person’s body, there is a physiologic change. The goal has been to see why needles at specific points on meridians, or channels, have the actions and effects that they do.
The biological functions of all living animal organisms are essentially electrical and chemical. Many of the acupuncture points are located near or on the junction of nerve bundles. In Western medical terms, studies indicate that acupuncture influences the central and peripheral nervous systems; sugar, cholesterol, and triglyceride levels in the blood; the functioning gastrointestinal system; and activity in the endocrine system.
Blood samples taken from humans and animals before and after acupuncture treatment show a distinct change in blood chemistry. Stimulation by acupuncture may also activate the hypothalamus and pituitary glands, resulting in a broad spectrum of effects.
The most extensively researched physiological reaction to acupuncture has been the release of substances in the brain known as endorphins, the body’s natural painkillers. It is thought that acupuncture needles stimulate peripheral nerves in muscles that send messages to the brain to release endorphins, which then do their work of blocking pain messages from reaching the brain.
Alteration in the secretion of neurotransmitters and neurohormones and changes in the regulation of blood flow have been documented. Studies show that acupuncture releases serotonin, a brain chemical that affects mood and emotions—making it useful in treating depression—plus a hormone called ACTH, which stimulates anti-inflammatory effects. There is also evidence that there are alterations in immune functions produced by acupuncture.