Among the documented effects of Reiki, stress reduction may be the most applicable in the modern world. In one 2008 experiment conducted at the Laboratory for the Advances in Consciousness and Health at the University of Arizona, Reiki was shown to mitigate heart rate increases in rats exposed to an audible stressor. In the experiment rats, which were used to eliminate human biases, were exposed to a white noise frequency known to increase their heart rates. When exposed to Reiki, both the stressed and unstressed rats experienced reduction in heart rates. Conversely, when exposed to “Sham-Reiki”, no significant change in heart rate was observed. These findings suggest a stabilizing effect of Reiki on heart rate within the experimental group and reinforce its empirical use of stress reduction within humans.
Baldwin AL, Wagers C, Schwartz GE. Reiki improves heart rate homeostasis in laboratory rats. J Altern Complement Med. 2008 May;14(4):417-22. doi: 10.1089/acm.2007.0753. PMID: 18435597.