What Is Reiki? History, What Happens in a Session, and What Research Does and Does Not Show

Reiki is a hands-on practice in which a practitioner rests their hands lightly on a person, or holds them just above the body. It began in Japan, spread abroad, and later returned to Japan, which gives it an unusual history.

This article covers Reiki’s history, what happens in a session, and what research does and does not show. Every study and official statement below was checked against the original, and each one is linked (checked November 2026).

The short answer

What happens: you lie down or sit fully clothed while the practitioner places or holds their hands near you. Many people say they feel relaxed.
What research shows: a US government health agency says Reiki has not been clearly shown to be effective for any health-related purpose, and that there is no scientific evidence for the energy field it is based on. Some reviews report benefits for anxiety, but the studies are few and the question is not settled (section 3).
How to approach it: never as a replacement for medical care. If you are being treated for an illness, tell your doctor and treat a session as a time to relax.

1. History

Reiki is traced to Mikao Usui (1865 to 1926) in Japan. Within the tradition, it is said that he arrived at the method after a period of practice on Mount Kurama near Kyoto.

His student Chujiro Hayashi passed it on to Hawayo Takata, a Japanese American who taught it in Hawaii, and from there it spread through the United States and Europe. In Japan it faded for a time and later returned from abroad.

The ki in Reiki refers to the East Asian idea of life energy, similar to qi in qigong or prana in yoga.

2. What Happens in a Session

You sit or lie on a treatment table, fully clothed
The practitioner rests their hands lightly on places such as the head, shoulders or abdomen, or holds them a few centimeters away
A session usually lasts several tens of minutes, depending on the practitioner

People often say they felt warmth from the hands, relaxed deeply, or fell asleep. Experiences vary, and some people feel nothing in particular.

3. What Research Does and Does Not Show

Here are the studies and the official statement we checked. Where their conclusions point in different directions, we show both.

Source	What was examined	Conclusion	Keep in mind
US National Center for Complementary and Integrative Health (NCCIH) updated December 2018	Research on Reiki overall	Not clearly shown to be effective for any health-related purpose. No scientific evidence for the energy field. No harmful effects shown	Studied for pain, anxiety and depression, but most research was not high quality and results were inconsistent
Lee et al. 2008 systematic review	Nine randomized controlled trials	Evidence insufficient to call Reiki an effective treatment for any condition	Trials were small with many methodological problems
Joyce and Herbison 2015 Cochrane review	Trials in people with anxiety or depression	Not enough evidence to say whether Reiki helps	Only a few dozen relevant participants in total
Zadro and Stapleton 2022 systematic review	14 trials comparing Reiki with a sham for mental health symptoms	Reiki did better than the sham for some symptoms	Few studies in each area; the authors call the findings inconclusive and note risk of bias
Guo et al. 2024 meta-analysis	Studies on anxiety (824 participants)	Reduced anxiety	Included non-randomized studies; results were less consistent before surgery and in cancer patients

What this adds up to: many people find a Reiki session relaxing, and some studies report lower anxiety. But the studies are small and uneven, and the evidence does not support saying that Reiki works. The energy it is based on has not been shown to exist.

What we changed: an earlier version of this article said that Reiki is used in medical facilities worldwide and in more than 800 US hospitals, that over 5 million people practice it, named specific hospitals, stated that improved heart rate variability and lower cortisol are measured facts, that the effect of touch is certain, that Reiki relieves cancer-treatment side effects, that pain really decreases even with placebo, and described "healing reactions." We could not support these, or they overstated the research, so we removed them.

4. If You Want to Try It

Do not use it instead of medical care: diagnosis and treatment belong with a doctor. Walk away from anyone who says Reiki will cure you or that you can stop medication
If you are in treatment, tell your doctor
Check the cost first: session prices, packages and course fees. Be careful with expensive courses or pressure to buy special attunements
Say how you want to be touched: you can ask for hands-off only, or for certain areas to be avoided

5. A Simple Hands-On Pause You Can Do Yourself

Reiki traditions hold that the practice requires training and attunement. What follows is not a Reiki method, just a short way to relax on your own.

Sit or lie comfortably somewhere quiet
Breathe slowly and rest your palms on your chest or belly
Notice the warmth of your hands and the rise and fall of your breath for a few minutes

There is no need to expect healing. Notice for yourself whether it helps you relax.

6. FAQ

Q1. Is Reiki a religion?
A. It is not tied to a particular religion, though each school has its own ideas and customs.

Q2. How soon will I notice an effect?
A. Some people feel relaxed after a session, but no research has established how the number of sessions relates to any change.

Q3. How many sessions should I have?
A. There is no set number. For ongoing symptoms, see a doctor rather than relying on Reiki.

Q4. Is it safe for children or during pregnancy?
A. Light touch places little strain on the body. For any health concern, see a pediatrician or obstetrician first.

Q5. Can it be done on pets?
A. No research has shown an effect. If your pet is unwell, see a veterinarian.

Q6. Are there side effects?
A. NCCIH says no harmful effects have been shown. The main risk is delaying needed treatment by relying on Reiki. If you feel worse after a session, do not assume it is part of healing; talk to a doctor.

Q7. Which illnesses can Reiki cure?
A. None has been shown. Do not trust a practitioner who promises a cure.

7. Conclusion

Reiki is a hands-on practice that began in Japan and spread worldwide. Many people find a session relaxing. Research has not clearly shown that it works, and the energy it describes has not been shown to exist.

If you try it, do not use it in place of medical care, check the cost, and treat it as one way to rest.

10 November 2026: We rewrote this article after checking the studies and official statements against the originals, and removed figures and medical claims we could not support.

References

NCCIH. Reiki (last updated December 2018). US National Center for Complementary and Integrative Health (NCCIH)
Lee MS, Pittler MH, Ernst E. (2008). Effects of reiki in clinical practice: a systematic review of randomised clinical trials. International Journal of Clinical Practice 62:947-954. doi:10.1111/j.1742-1241.2008.01729.x
Joyce J, Herbison GP. (2015). Reiki for depression and anxiety. Cochrane Database of Systematic Reviews CD006833. doi:10.1002/14651858.CD006833.pub2
Zadro S, Stapleton P. (2022). Does Reiki benefit mental health symptoms above placebo? Frontiers in Psychology 13:897312. doi:10.3389/fpsyg.2022.897312
Guo X, et al. (2024). Therapeutic effects of Reiki on interventions for anxiety: a meta-analysis. BMC Palliative Care 23:147. doi:10.1186/s12904-024-01439-x

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This article does not guarantee any medical or health benefit and is not a substitute for professional medical care. If you have any health concerns, please consult a physician or other qualified professional.