Does real acupuncture increase parasympathetic tone compared to placebo acupuncture?
Real acupuncture appears to increase parasympathetic tone compared to placebo, though results should be interpreted cautiously due to study heterogeneity.
the results of this meta-analysis suggest that real acupuncture has superior effect over placebo acupuncture in increasing parasympathetic tone and in this way may improve physical well-being. Due to the quality of primary studies and degree of heterogeneity the results should be interpreted cautiously.
Hamvas et al. (Tue,) studied this question.