There is now a body of evidence that traditional acupuncture enhances and regulates the immune system. Both in healthy people and in people with reduced immunity or illness (elderly people, women with anxiety and cancer patients have been studied) acupuncture has been shown to:

• Regulate the immune system, having an immunomodulatory effect.

• Enhance the activity of the immune system, influencing a range of immune cells: lymphocytes, natural killer (NK) cells, and cytokines which stimulate immune cells, such as interleukins, IFNγ and TNFα (a cytokine produced by NK and CD4 and CD8 cells).

Trials on animal models have produced similar effects.

In one study on healthy people, cellular or TH-1 immunity was found to be elevated to nine times its previous level 8 days after a single acupuncture treatment.

In a study on elderly people, acupuncture increased the activity of T-lymphocytes to the level of that in young adults, suggesting that acupuncture can counter the lowering of immune function with age.

A study on women with anxiety, a group which has been found to have impaired immune function, concluded that acupuncture effectively regulates the immune system in anxious women. The effect was strongest 72 hours after treatment and a positive effect on immune function was sustained for 30 days after a course of 8 treatments.

A meta-analysis of 31 studies of acupuncture on 1,818 lung cancer patients concluded that acupuncture enhances immune function, increasing the activity of T lymphocytes CD3 and CD4, and natural killer cells.

In another study acupuncture was also found to both enhance the immune response to external threats and reduce markers associated with an over-active, allergic response, having a balancing or modulatory effect on the immune system.