The specific mechanism by which cupping exerts its therapeutic effects remains unknown. However, several theories have been proposed to explain its physiological benefits, as discussed below. [7]
Pain Gateway Theory
This theory proposes that the touch, pressure, and vibration sensations generated during cupping therapy selectively stimulate large nerve fibers. This stimulation inhibits the transmission of pain signals to the brain via the dorsal horn of the spinal cord. The increased stimulation of peripheral pain receptors resulting from cupping leads to the upregulation of receptor units, subsequently activating large nerve fibers. These large nerve fibers respond to stimuli, and the pumping mechanism used to create suction during cupping may contribute to pain relief.
The theory of diffuse harmful inhibitory controls (DNIC)
This theory proposes that pain in one part of the body can be suppressed or masked by pain in another area. More specifically, DNIC refers to findings from animal studies demonstrating lower brainstem-mediated pain inhibition. In humans, this phenomenon is called conditioned pain modulation (CPM). Effective use of CPM requires conditioning to achieve a reduced pain response. Cupping therapy has been used to treat idiopathic pain syndromes. However, the precise mechanism by which DNIC works in cupping therapy is not fully understood. Various hypotheses have been proposed, including possible distraction caused by the sensation of cupping, induction of the DNIC response, or stimulation of a deoxygenating effect. [7]
Blood Detoxification Theory
This theory primarily applies to wet cupping. According to it, elevated concentrations of several substances are observed in the blood drawn during wet cupping, including uric acid, cholesterol, urea, and triglycerides. Furthermore, blood extracted through wet cupping is believed to contain higher levels of red blood cells, hemoglobin, hematocrit, viscosity, and mean corpuscular hemoglobin concentration. This theory has been applied in detoxification protocols, particularly for aluminum, mercury, silver, and lead.