Description
Reiki, a form of energy healing that originated in Japan, is a system of natural healing administered by the laying on of hands and by transferring energy from the Reiki practitioner to the recipient. It is sometimes used as a palliative or supportive treatment of cancer patients. Only few studies of Reiki have been published; most have methodological limitations and are thus not conclusive.
Efficacy
Anxiety: There is some evidence that Reiki may reduce anxiety but this is not specific to cancer. Studies in cancer are too poor quality for any conclusions to be made.
Quality of life: There is preliminary evidence that Reiki may improve quality of life in cancer, but studies are too small to be conclusive.
Pain: There is some evidence that Reiki may reduce pain but this is not specific to cancer. Studies in cancer are too poor quality for any conclusions to be made.
Fatigue: There is no reliable evidence that Reiki reduces fatigue in cancer.
Neurotoxicity: There is no reliable evidence that Reiki reduces neurotoxicity in cancer.
Safety
Reiki is not believed to have the potential to cause serious direct harm.
Citation
Ava Lorenc, Helen Seers, Edzard Ernst, CAM Cancer Collaboration. Reiki [online document]. July 8, 2021.
Document history
Latest update: July 2021
Next update due: July 2024
Description and definition
Reiki is a form of energy healing, which is based on the belief that healers can channel healing “energy” into a patientand effect positive results. Several types of energy healing exist including therapeutic touch and qigong. The word Reiki comes from the Japanese word “Rei” which means “Universal Life” and “Ki” which means “Energy”. In Reiki practice, the practitioner uses light touch or holds their hands slightly above the body of a client and believes to channel Reiki “energy” into the client (Birocco 2012; Jonas 2005).
Background and prevalence
Reiki has its roots in ancient Tibetan Buddhism. The Japanese theologian and Buddhist monk Mikao Usui is said to have rediscovered the technique in the late 19th century/early 20th century. Before his death, Mikao Usui taught several Reiki masters. One of them, Chujiro Hayashi, is credited with further developing the Usui system of Reiki by adding hand positions to more thoroughly cover the body as well as changing and refining the attunement process. Using his improved system, he trained several more Reiki Masters, including a Japanese-American woman Hawayo Takata who is credited with introducing Reiki in the Western World on her return to the USA (IARP 2020). More recently, Reiki has been more widely used in other countries as well.
There are few reliable data to accurately describe its prevalence of use in cancer patients (Lorenc 2010; Pierce 2007). While some authors claim it is commonly used by cancer patients (Barnett 2002; Lorenc 2010) other data suggest that Reiki use is rare (Talmi 2005). In the UK for example, 43% of those cancer-units which offer some form of CAM also provide Reiki as a supportive or palliative therapy (Egan 2912).
Alleged indications
Reiki is being used for stress reduction and relaxation; it is also used to maintain wellbeing and thus to help the treatment of most human conditions or symptoms (IARP 2017). This includes symptoms related to cancer treatments; anecdotal evidence suggests that Reiki can alleviate cancer symptoms such as pain or anxiety. Some advocates would go further and claim that Reiki can influence the natural history of malignancies.
Mechanisms of action
The Reiki ‘energy’ allegedly stimulates ’balance’ and self-healing. The term is in inverted commas because it is not energy in the sense science would define it. Some authors claim that Reiki operates on a physiological level causing molecules within the body to attain higher energy levels. Reiki is said to remove ‘energy’ blocks (Barnett 2002). From a more scientific point of view, Reiki's effects have not been documented; its mechanisms are unexplained and biologically implausible.
Application and providers
The Reiki-practitioner either uses light touch or hands-off where they will hold their hands slightly above the body, or heals at a distance by sending Reiki ‘energy’ to the patient. The Reiki practitioner moves through specific standard Reiki hand positions beginning at the person’s head or feet. Therapy can be as often as desired, typically several times per week. A course of treatment might consist of six or more sessions and is determined by the preferences or needs of the patient and the practitioner. Reiki is usually used in addition to conventional therapies in any setting. Reiki is also practised as self-care (IARP 2017).
Legal issues
In most countries, Reiki-practitioners are not regulated healthcare professionals. Anyone regardless of education, training or experience, can claim to be a Reiki-practitioner or Reiki-master. Providers are initiated by an experienced Reiki-master up to three levels of attunement. In some countries, e.g. the UK, Reiki-practitioners are not allowed to claim to cure cancer.
Supportive care
No systematic review specifically on Reiki for cancer exists. Three reviews (Lee 2008, Agdal 2011, Thrane 2014) have looked at either Reiki across all diseases or at the broader field of “energy healing” for cancer. They all include the same five Reiki pilot randomized controlled trials (RCTs) which all suffer from methodological limitations including very small sample sizes, inadequate design and poor reporting (low quality evidence). Since the publication of the reviews, three RCTs (Chirico 2017; Alarcao 2016; Catlin 2011) and another three pilot controlled clinical trials (CCTs) have been published (Demir 2015; Orsak 2015; Clark 2012).
Lee (2008) published a systematic review of 9 RCTs of Reiki as a treatment for any condition including cancer for which trial data were available. Although results were not separated by condition so we cannot identify outcome-specific data for cancer, this is the only systematic review available so we have included it here. This SR concluded that there is insufficient evidence that Reiki is effective for depression, anxiety, stress and helplessness, and most studies had serious methodological limitations.
Description of studies
Anxiety
Anxiety was evaluated by a non-systematic review (Thrane 2014), and two subsequent trials, one RCT (Chirico 2017) and one pilot CCT (Demir 2015). The 2014 non-systematic review calculated the overall effect of Reiki for all health conditions, including cancer, and found four randomised controlled trials where Reiki may be beneficial in reducing anxiety (Thrane 2014). However, this review concluded that more high-quality research with larger sample sizes, standardised treatment protocols and consistent randomisation are needed. This review was also not specific to cancer and included non-cancer trials in its overall conclusion.
The RCT (n=110) of Reiki compared to standard care for breast cancer patients during the pre-surgery phase found significant reductions in anxiety (Chirico 2017). However, this study is very low quality, with a small sample, no power calculation, and no details of randomisation. The pilot CCT (n=18) compared distant Reiki to usual care for pain, anxiety and fatigue in patients with cancer (Demir 2015). Significant reductions in measures of anxiety (generated by a VAS numerical rating) were found for the Reiki group, however, the number of participants was very small, there are no details of randomisation, the two groups were not comprised of similar sexes of participants and the conclusions of the paper cannot be supported by the data.
A ‘critical’ review (Agdal 2011) of various types of energy healing specifically for cancer included 6 quantitative and two qualitative studies. Although they identified studies which did report reduced anxiety, they concluded that “none of the included trials met a standard which produces reliable results”
Quality of life and wellbeing
An RCT randomised 189 cancer patients receiving chemotherapy in three groups: standard care, placebo-Reiki or Reiki (Catlin 2011). The main outcome measures were self-reported comfort and wellbeing. The analyses showed that both Reiki and placebo-Reiki were superior to standard care. This seems to suggest that Reiki is associated with sizable placebo effects but has no specific effects.
Alarcao (2016) presented an RCT of the effects of Reiki on quality of life for patients with blood cancer. Fifty-eight people were randomly assigned to Reiki and 58 to sham Reiki (control), the interventions were two one-hour sessions per week for 4 weeks. The methodology of the trial is stated as double-blind, however, no specific details on how the blinding occurred for those giving the Reiki, or receiving it, are given; also the success of blinding is not reported. Results showed a significant benefit of the Reiki group for general, physical, environmental and social aspects of the WHOQoL Brief measure. It must be noted that a large number of the control group (n=16) died before the trial was completed, however this attrition occurred after randomisation, and those that died had the worst prognosis – those with the worse prognosis were equally represented in the experimental arm. Larger sample size testing would be needed to improve the reliability of this trial.
A pilot RCT evaluated the effect of Reiki compared to education-only control on quality of life, mindfulness and psychological distress in patients with chemotherapy-induced peripheral neuropathy (n=26) (Clark 2011). They did not find any significant effects. This was a well-conducted pilot, although their conclusions do not seem to reflect their results, and the small sample size meant only 5-7 patients in each group.
Orsak et al. (2015) conducted a pilot RCT (n=36) on breast cancer patients who received either Reiki, a companion, or usual care during chemotherapy (Orsak 2015). Measures of quality of life (FACT B – Functional Assessment of Cancer Therapy: Breast Cancer version) and mood (Profile of Mood States) were found to be better than usual care in the Reiki and companion groups. This study would have benefitted from an additional sham Reiki condition, also, an increased sample size and blinding participants to their intervention groups would have been desirable.
Pain
The review by Lee et al (2008) also found insufficient evidence that Reiki is effective for pain in cancer. The review by Thrane et al (2014) found some trials where Reiki may be beneficial in reducing pain, but this was not specific to cancer (Thrane 2014). A pilot CCT found significant reductions in pain for distant Reiki compared to usual care, but this study has major limitations as described above (Demir 2015). Agdal et al (2011) identified 6 studies which did report reduced pain but they concluded that “none of the included trials met a standard which produces reliable results”
Fatigue
A pilot CCT found significant reductions in fatigue for distant Reiki compared to usual care, but this study has major limitations as described above (Demir 2015). Agdal et al (2011) identified studies which did report reduced fatigue but they concluded that “none of the included trials met a standard which produces reliable results”
Neurotoxicity
The pilot RCT comparing Reiki compared to education-only control for patients with chemotherapy-induced peripheral neuropathy found no change in neurotoxicity outcomes (Clark 2011).
Other outcomes
Agdal et al (2011) identified studies which did report a variety of other outcomes but they concluded that “none of the included trials met a standard which produces reliable results”.
Antitumour treatment
No clinical studies evaluating antitumour effects were identified.
Prevention
No clinical studies evaluating preventative effects were identified.
Adverse effects
None known
Contraindications
None known
Interactions
None known
Warning
None known
Other problems
None known
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