Is there science on Reiki?

image: iStock Photo. Therapist holding hands over head of pretty young Black woman to transfer energy during healing reiki session

When I began researching for my new book, ‘Why Woo Woo Works’, one of the first subjects I investigated was Reiki.

Reiki is really popular nowadays, but a lot of people unfamiliar with it still refer to it as woo woo, meaning, to them, there’s nothing in it.

Well, it turns out that there is quite a lot of science on it. A 2018 meta-analysis of four randomised controlled trials (RCTs) into the use of Reiki to reduce pain over a range of medical conditions found that it produced a statistically significant reduction in pain.

Similarly, a 2019 review in the British Medical Journal Supportive & Palliative Care, reported that “Reiki therapy is useful for relieving pain, decreasing anxiety / depression, and improving quality of life in several conditions.”

Sometimes these studies are done in hospitals. One took place at Bryn Mawr Hospital in Pennysylvania with patients who had undergone total knee replacement surgery, a very common surgery in the US. Twenty-three patients received reiki and 20 didn’t – for comparison. Pain was assessed before the operation and each day afterwards. Those who received the reiki were in significantly less pain than those who didn’t. 

The results were so compelling, in fact, that the hospital soon established a dedicated reiki program where 10 nurses were trained and certified in reiki. Now, knee anthroplasty patients there are routinely offered reiki and enjoy a little bit less pain as a consequence.

So what is reiki, exactly? The word reiki is composed of two Japanese words: rei, which means ‘hidden force or higher power’, and ki, which means ‘life energy’. It’s believed to have originated in the early 20th century after Zen Buddhist Mikau Usui undertook a 21-day fast and penance on Mount Kurama. The story goes that he became enlightened with the knowledge of reiki on the 21st day and was healed of his illnesses. On his return to his village, he established a clinic and began offering reiki freely to people.

It’s listed as an an ‘energy healing’ technique or a ‘biofield therapy’. Admittedly, these at first sound woo-woo, but a biofield is simply an electric or magnetic field that’s generated by a biological organism. 

When you plug, say, a phone charger into a wall socket, the electricity (or electric field) is generated by a physical process, so we just call it an electric field in plain language. But when it’s generated by ions like Calcium “Ca(2+)”, Sodium “Na(+”) and potassium “K(+)” that are moving in and out of cells, it’s called a biofield to distinguish the source of the electric field. So, you have a biofield. I have a biofield. All people, animals, plants, birds, fish, and insects have a biofield, as do all of your cells.

Any changing / moving electric field generates a magnetic field. So not only do you have lots of little electric fields in your body and a sum field – the sum of all these electric fields; your overall biofield – but you also have lots of little magnetic fields and larger ones that emanate from areas where there is lots of blood flow (lots of moving electric fields) – like the heart.

The US National Center for Complementary and Integrated Health writes that the goal of a reiki practitioner is to direct energy to help facilitate the person’s own healing response. In a sense, what’s being directed is electric and magnetic fields. While we’re not in the business of studying the individual movement of electric and magnetic fields while a practitioner practices reiki, results in large part almost certainly come from this process.

It is believed that the practitioner’s own state is therefore of paramount importance. Research at the Heartmath Institute in Boulder, Colorado, invited volunteers to sit in close proximity. When one person was feeling empathy, compassion, love, or any similar ‘heart focused’ state, their heart rhythms guided (or entrained) the brain waves of the person they were close to. 

This process is believed to occur in two ways. First, through the magnetic field of the person’s heart as they feel those positive states, which then entrains the magnetic field of the heart in the person they are sitting with, much in the same way that large pendulums entrain smaller ones, and the second is through a brain circuit known as the mirror neuron system (MNS), which is responsible for the well-known phenomenon of emotional contagion (where you tend to feel the same emotions as the people you spend most time with).

When you are in a such heart-focused state, you help people close to you move towards a similar state. I think most of us have probably noticed this in our own lives, either as the one affecting another person, or as the one being affected. There are people that most of us know who have a natural warming presence. You may be one of them! That you come to feel better (mentally and / or physically) around them is known as the ‘natural healer effect’.

Reiki practitioners are trained to reach these optimum states when working with clients. Their goal is one of service, in the ‘highest good’ of the client. Their predominant state is empathy.

There’s another process that operates at the same time as this. Reiki is typically a restful, or restorative, experience. This in itself assists the body’s natural healing processes as the autonomic nervous system moves towards a greater parasympathetic (rest and digest) state. During this time, the body’s natural healing systems, which includes the immune system, are able to work more optimally. Whether most of the effects of reiki comes from the state of the healer or the restorative experience, we don’t know for sure. It’s most likely due to a bit of both. The experience itself helps to assist the body’s natural processes, and the state of the healer can assist even more, if it’s a heart-focused one.

Ultimately, there’s nothing actually woo woo going on, just physical processes that most people have little knowledge of. Sometimes, it’s just our lack of awareness of available knowledge or research that betrays our attitudes to things. We call things woo woo, not because we’re experts in those areas and know if something is true or not, but because we’re not experts and we simply don’t know about the available knowledge or research.

There is a great deal of available research. I’ve cited quite a bit in my book, ‘Why Woo Woo Works’. In it, I also explain why I’d love to see a closer integration between mainstream treatments and complementary practices. 

It doesn’t have to be one or the other. Yes, sometimes much more of one and less of the other, especially for acute or serious conditions, but at other times perhaps more of the other and less of the first. And then at other times, a blend of both.But I think the long-term future of healthcare will be best served with a blend of allopathic and complementary, mainstream and holistic, West and East.

Read more about the science behind reiki in my new book, Why Woo Woo Works (Hay House, September 2021).

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  1. Bernadette Hillewaert on December 30, 2021 at 3:26 pm

    This has resonated so much with me. I often compare how Reiki works with électricity. I recall a case at the hospice where I volunteered , must have been 2017 or 2018, where after a Reiki session, not only was the parient ‘recharged’ so was the patients electric wheelchair ! Everybody was astounded … but it is science . My biofield must have been.supercharged that day !

  2. Gilly Ivory on January 15, 2022 at 12:24 pm

    Hi David,
    I love your article about reiki, it’s particularly relevant to me as I am a reiki master and an orthopaedic nurse working in Pre admission so assessing patients fitness for anaesthetic prior to their surgeries, most commonly hip and knee replacements.
    Having a medical type background I prefer things to be evidence based and when I was learning and doing my reiki attunements I was lucky enough to have a friend who had a practise doing reflexology etc , so I was able to give anyone expressing an interest in reiki a treatment without knowing anything about them being under my friends supervision. Problems I then “picked up” could be verified after.
    I was aware of reiki being used in palliative care in London hospitals but was unaware of any studies being used in joint replacement surgery so I would like to look into that further
    We now have a younger knee surgeon who I think might possibly not laugh me out of the room at the suggestion of a study! He has got the trust to pay for two robots to assist him in theatre doing his knees so who knows!
    Another therapy I studied was crystal therapy. I nearly completed the year but in the end had to stop as my increasing and overwhelming thought was that it was utter hokem.
    I would value your opinion, possibly there maybe some factual evidence somewhere to support at least some of it.

    Kind regards
    Gilly Ivory

  3. Alex Edgar on April 28, 2022 at 11:49 am

    I am also busy looking at evidence for Reiki and other energy healing techniques. On the whole, it seems like the scientific evidence shows that energy healing works. But it can’t explain how. The problem with biofields is that they are local, and energy healing appears to be non-local – with the exception of Chi-based therapies. The other problem is that what clients and practitioners describe does not tally with electro-magnetic effects. It is much richer and more complex. So yes, it all seems to be real and effective. No. We don’t seem to know how it works.

  4. Woo-woo to true-woo - David R Hamilton PHD on August 19, 2022 at 12:12 pm

    […] However, it can be better understood as how the state of the healer influences, and calms, the state of the patient. […]

  5. […] Reiki is still considered an alternative therapy by many, scientific research has begun to shed light on its potential effectiveness. Many studies have demonstrated the positive […]

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