It’s based on the idea that we all have an unseen “life force energy” that flows through our bodies, according to the International Center for Reiki Training. A Reiki practitioner gently moves her hands just above or on the client’s clothed body, with the intention of reducing stress and promoting healing by encouraging a healthy flow of energy. A survey conducted by the National Institutes of Health (NIH) in 2008 found that 1.2 million adults and 161,000 children in the United States had received energy healing therapy like Reiki in the previous year. Reiki is now used by a growing number of Americans who believe it helps with relaxation, anxiety, pain management, and depression, according to a past pilot study. Here’s more on the reported benefits of Reiki, its history, and how to get started. “I’m an open channel, and [the Reiki recipient’s] body takes that energy and does whatever it needs with it,” explains Vickie Bodner, a licensed massage therapist and Reiki master at the Center for Integrative Medicine at Cleveland Clinic in Ohio. The word “Reiki” is a combination of two Japanese words: “rei,” which means “God’s wisdom,” or “the higher power,” and “ki,” which means “life force energy,” according to the International Center for Reiki Training. “Ki is the life force energy that animates all living things,” says Joan Maute, a licensed Reiki master teacher who practices in Waikoloa, Hawaii, and Charlottesville, Virginia. Put together, and “rei” and “ki” mean “spiritually guided life force energy,” notes the International Center for Reiki Training. Reiki is taught according to the Japanese tradition of the sensei (teacher), who passes the knowledge to the student through attunement, an initiation ceremony that is thought to help open the student’s energy channels to facilitate the flow of healing energy, and potentially help improve health, according to past research. Once opened, these channels remain accessible to the practitioner for the rest of their life, per the International Center for Reiki Training. “[Reiki] is a spiritual practice, like meditation is a spiritual practice,” says Pamela Miles, a New York City–based Reiki master and researcher who has collaborated with the medical schools at Harvard and Yale universities to develop Reiki programs there. Reiki, despite its spiritual components and roots, may be and is often used therapeutically (more on this later), including in a secular way. It’s not a religion and is not associated with religious practice. Reiki is taught at three levels. First-level practitioners can practice on themselves or others through light touch; second-degree practitioners can practice distance healing; and third-degree or master level practitioners can teach and initiate others into Reiki, according to a literature review. There are theories. One popular theory involves a phenomenon known as the “biofield.” The biofield is an electromagnetic field that permeates and surrounds every living being. In humans, this field extends 15 feet or more from the body, according to Ann L. Baldwin, PhD, a Reiki researcher and professor of physiology at the University of Arizona’s College of Medicine. The heart, for example, produces an electrical field — measured through an electrocardiogram, or ECG — to regulate heartbeats. The brain also produces an electrical field, though at a lower level than the heart. In fact, all of the body’s cells produce positive and negative electrical charges, which then create magnetic fields, per the aforementioned past literature review. According to this theory, the interaction between two human magnetic fields may explain the effects of touch therapies like Reiki. It is thought that the biofield is the energetic force that guides bodily functions, and that Reiki energy influences the biofield. “[The biofield] is thought to cause dynamic changes in its vibrational qualities that alter physiological and psychological functions in living beings,” Dr. Baldwin says. Quantum physics, the study of how the incredibly small particles that make up matter — electrons, neutrons, protons, and photons — behave, and attempts to explain the interactions of energy and physical matter. Quantum physicists have found that these tiny particles of energy can be in more than one place at one time (both a wave and particle at the same time, depending upon how it is examined, per the University of Pittsburgh), and that thought or intention may change how the particles work. In essence, the Reiki practitioner may be able to gather and direct biofield energy to the recipient through thoughts and intentions. On its website, the NCCIH notes that there is insufficient scientific evidence at this time to verify the existence of this energy field. For example, research suggests that Reiki may lower anxiety, stress, and pain in people undergoing surgery. In a study published in the March-April 2017 issue of Holistic Nursing Practice of patients undergoing knee replacement surgery, researchers separated 46 patients into three groups: One group received three or four 30-minute Reiki treatments throughout their hospital stay; a second group received the same number of placebo (sham) Reiki sessions; and a third group received neither Reiki nor sham Reiki. Every group also received standard medical care. Researchers found that those who received Reiki saw significant reductions in pain, blood pressure, breathing rate, and anxiety pre- and post-surgery and greater reductions than the other groups. Reiki may also improve mood and sleep: A past study found that college students who received six 30-minute Reiki sessions reported greater improvements in stress, mood, and sleep (especially those with higher anxiety and depression) than the control group. Other research suggests that Reiki and other forms of energy therapy may help patients with cancer improve pain control and anxiety levels. A main benefit of Reiki (which leads to a lot of other benefits) is stress reduction, Miles explains. “Our bodies cannot heal when they’re in a stressed state all the time.” Reiki gives your body a break from the stresses of daily life, potentially helping relieve tension and return you to a state of relaxation. Once in this state, your body may be better able to heal any damage brought on by stress, injury, or disease. “By helping a person experience deep relaxation, Reiki [may] enhance and accelerate our own natural healing process, because the body can stop being stressed and focus on healing itself,” Maute says. For example, past research shows that a single Reiki session may help your autonomic nervous system, the primitive part of your nervous system that you don’t fully, consciously control (it’s responsible for things like heartbeat and breathing), move from a sympathetic-dominant, or “fight-or-flight” state, to a parasympathetic-dominant, or “rest-and-digest” state, Miles explains. Your brain is constantly processing information in a region called the hypothalamus, which then sends signals through your autonomic nervous system to the rest of your body to either stimulate or relax different functions, such as heart rate, blood pressure, breathing, and digestion, according to Harvard Health. When you experience stressors like poor sleep, a confrontation with a friend, or even exercise, your sympathetic nervous system reacts, releasing hormones like epinephrine, among others, and increasing heart rate and blood pressure (the fight-or-flight response that gets the body ready to deal with potential dangers), according to Britannica. But when your body is constantly under stress (or is activated by prior more severe stressful experiences, such as trauma and resultant PTSD), this response can shift into overdrive, which can lead to problems like greater risk of heart disease, per a past article. “The parasympathetic-dominant state is the state we are meant to live in,” Miles says. And Reiki helps to support one’s autonomic nervous system toward that state of safety, rest, recovery, and ease. In a past study, 21 healthcare professionals with burnout (a work-related mental health condition characterized by mental exhaustion, emotional detachment, and a lowered sense of personal accomplishment) received a 30-minute Reiki session with an experienced therapist, as well as a 30-minute placebo treatment with an inexperienced therapist who mimicked the Reiki treatment. The two treatments were separated by one week; participants were randomly assigned their treatment order, and they weren’t told which treatment they were getting during which session. Researchers measured heart rate variability, or the variation in time between each heartbeat, to gauge how the nervous system responded to the therapy. A low score indicated there was little variability between heartbeats, signaling that the sympathetic, or fight-or-flight, component of the nervous system might be working overtime, and the stress level was high. Meanwhile, a high score meant greater variability in between heartbeats, and that the parasympathetic, or rest-and-digest, component of the nervous system had kicked into higher gear. Researchers found that heart rate variability was greater after the Reiki session, which suggests (using a very quantifiable physiological measurement) that Reiki helped the stressed nervous system relax. Keep in mind that Reiki is a form of complementary therapy, per the NCCIH, which means that it is intended to work alongside — not replace — other medical and therapeutic techniques. “Because Reiki is so balancing to the system overall, it can potentially benefit any situation,” Miles says — but it should not be used as a substitute for other treatments your healthcare providers have prescribed, or be used against medical advice. After three weeks of fasting and meditation on Mount Kurama, a sacred mountain in the north of Kyoto, Japan, Usui claimed to have first experienced feeling Reiki energy. Though Usui had been starving and near death from fasting, the burst of intense healing energy gave him a sense of vitality and awareness that he’d never felt before. Shortly after his experience, Usui opened a clinic in Tokyo to practice the healing technique. (Some of the potential physiological effects of Reiki, like changes in cortisol levels, heart rate variability, and body temperature have since been examined in research.) After this, Hawayo Takata, a Japanese-Hawaiian Reiki master, began teaching Usui’s modality in Hawaii in the 1930s, and it traveled to the rest of the United States in the 1970s. As early as the mid-1990s, physicians, nurses, and other medical staff who had learned Reiki began using the technique in hospitals around the United States, and Reiki continues to expand as more and more people experience benefits from it, per the International Center for Reiki Training. Today, Reiki is used in both hospital inpatient and outpatient settings as a complementary therapy for surgery, cancer, and AIDS, according to the IARP. Bodner, who has practiced Reiki at the Cleveland Clinic for about 10 years, has seen interest in Reiki grow. “The knowledge level has increased exponentially over the past few years,” she says. The only time Reiki practice can be dangerous is if the practitioner isn’t well trained, or isn’t truly practicing Reiki. Someone may claim to be practicing Reiki and instead be doing something risky or not practicing as a professional, Miles says. Remember, Reiki should never be an invasive treatment. Reiki practitioners should have worked in-person with a qualified Reiki master to be able to effectively deliver the treatment, Miles says. Reiki is often not covered by medical insurance, so the issue of cost should be considered by anyone seeking to start. Make sure you find a qualified professional Reiki practitioner (more on how to know whether someone is qualified or not below). It’s important to note that some patients may have an intensification of their symptoms temporarily, or could have an unexpected increase in nervous system activation, so if you have any known disorders, such as more severe anxiety disorder, or PTSD, it could be useful to discuss with your primary mental health provider first. This can also be mitigated by building trust with and telling your Reiki practitioner about any conditions you have, keeping the Reiki practitioner updated on how you’re doing throughout the session. Miles recommends wearing loose, comfortable clothing for your session. Avoid wearing anything tight or restrictive. You may be able to change your clothes at the practitioner’s office if necessary, but check beforehand. Dress in layers in case you get too warm or cool during the session, and keep in mind that the practitioner may have you roll onto your stomach at some point, so remove belts or bulky accessories. During the session, the practitioner will place his or her hands lightly on or near your body in a series of hand positions, including positions around the head and shoulders, the stomach, and the feet, as well as other positions depending on the client’s needs. Each hand position is held for roughly 3 to 10 minutes, depending on what the client needs in each position. (The International Center for Reiki Training has a helpful list of frequently asked questions if you’re considering trying Reiki.) The practitioner may or may not talk during the session, but typically there’s very little talking, according to Miles. Expect to feel deeply relaxed and content during the session. You’ll likely daydream, and you may even fall into a light sleep. “Sometimes people will say, ‘Oh, I fell asleep,’ but I’m not sure it’s physiological sleep,” Miles says. Instead, she believes people enter a deep meditative state that helps restore the nervous system. But personal experiences and sensations can vary widely depending upon the individual, and can be related to many factors, including characteristics of the practitioner, so be open to whatever emerges for you and then discuss after the session with the practitioner. There are some reputable Reiki training organizations out there that offer certifications and licenses, such as the International Center for Reiki Training (ICRT), the UK Reiki Federation, the Canadian Reiki Association, the Association of Australian Reiki Professionals, and the International Association of Reiki Professionals, according to Baldwin. ICRT offers a directory of professional Reiki practitioners, and you can search through their services. Or you can google practitioners in your area and see if they’ve been licensed or certified by one of these organizations, and whether they also have a primary license to provide care such as a nursing, medical doctor, or acupuncture license. The cost of a Reiki session will vary depending on where you go. At the Cleveland Clinic, a 60-minute session (50 minutes of hands-on therapy; 10 minutes for intake) costs $60, according to Bodner. Insurance may cover your Reiki sessions, but most likely you’ll pay for it yourself. “I’ve seen one person’s insurance cover it, but it’s really rare,” Bodner says. That said, if Reiki is part of your current treatment program, or given by a nurse or licensed care professional as part of routine care during a hospital stay, it may also be covered by insurance, according to the Earl E. Bakken Center for Spirituality and Healing. If you’re not sure, check with your insurance provider before your session.