- Chronic Regional Pain Syndrome
- Carpal Tunnel Syndrome
- Chronic Pelvic Pain in Women (Caused by Various Conditions, such as Endometriosis and Chronic Cystitis )
- Menstrual Pain
- Rheumatoid Arthritis
- Scar Tissue
- Sports and Fitness Support: Enhancing Performance
- Sports and Fitness Support: Enhancing Recovery
- Surgery Support
Long popular in Japan, magnet therapy has entered public awareness in the United States, stimulated by golfers and tennis players extolling the virtues of magnets in the treatment of sports-related injuries. Magnetic knee, shoulder, and ankle pads, as well as insoles and mattress pads, are widely available and are touted as providing myriads of healing benefits.
Despite this enthusiasm, as yet there is little scientific evidence to support the use of magnets for any medical condition. However, some small studies completed in the last few years suggest that various forms of magnet therapy might have a therapeutic effect in certain conditions. More studies are underway.
History of Magnet Therapy
Magnet therapy has a long history in traditional folk medicine. Reliable documentation tells us that Chinese doctors believed in the therapeutic value of magnets at least 2,000 years ago, and probably earlier than that. In sixteenth century Europe, Paracelsus used magnets to treat a variety of ailments. Two centuries later, Mesmer became famous for treating various disorders with magnets.
In the middle decades of the twentieth century, scientists in various parts of the world began performing studies on the therapeutic use of magnets. From the 1940s on, magnets became increasingly popular in Japan. Yoshio Manaka, one of the influential Japanese acupuncturists of the twentieth century, used magnets in conjunction with acupuncture . Magnet therapy also became a commonly used technique of self-administered medicine in Japan. For example, a type of plaster containing a small magnet became popular for treating aches and pains, especially among the elderly. Magnetic mattress pads, bracelets, and necklaces also became popular—again, mainly among the elderly. During the 1970s, both magnets and electromagnetic machines became popular among athletes in many countries for treating sports-related injuries.
Types of Magnet Therapy and Their Uses
The term magnet therapy usually refers to the use of static magnets placed directly on the body, generally over regions of pain. Static magnets are either attached to the body by tape or encapsulated in specially designed products such as belts, wraps, or mattress pads. Static magnets are also sometimes known as permanent magnets.
Static magnets come in various strengths. The units of measuring magnet strength are gauss and tesla. One tesla equals 10,000 gauss. A refrigerator magnet, for example, is around 200 gauss. Therapeutic magnets measure anywhere from 200 to 10,000 gauss, but the most commonly used measure 400 to 800 gauss.
Therapeutic magnets come in two different types of polarity arrangements: unipolar magnets and alternating-pole devices. Magnets that have north on one side and south on the other are known, rather confusingly, as unipolar magnets. Bipolar or alternating-pole magnets are made from a sheet of magnetic material with north and south magnets arranged in an alternating pattern, so that both north and south face the skin. This type of magnet exerts a weaker magnetic field because the alternating magnets tend to oppose each other. Each type of magnet has its own recommended uses and enthusiasts. (There are many heated opinions—with no supporting evidence—on this matter.)
More complex magnetic devices have also been studied—not for home use, but for use in physicians' offices and hospitals.
rTMS is also being studied for the treatment of amyotropic lateral sclerosis (ALS), Parkinson's disease , epilepsy , schizophrenia , obsessive-compulsive disorder , chronic regional pain syndrome, and tinnitus .
How Does Magnet Therapy Work?
Many commercial magnets have such a weak field that it is hard to believe they could affect the body at all. Some, however, are quite powerful and could conceivably cause effects at some depth. Nonetheless, biophysicists are skeptical that static magnets could significantly affect the body. (The moving magnetic fields of rTMS and pulsed electromagnetic therapy [PEMF] act differently, and there is little doubt that they can affect nerve tissue and possibly other parts of the body as well.)
What Is the Scientific Evidence for Magnet Therapy?
After 1 week of therapy, 68% of the participants using the strong magnets (called the treatment group) reported relief, compared to 27% in the control group. This difference was statistically significant . Two out of four other subjective measurements of disease severity also showed statistically significant improvements. However, no significant improvements were seen in objective evaluations of the condition, such as blood tests for inflammation severity or physician’s assessment of joint tenderness, swelling, or range of motion. This study suggests that magnet therapy may reduce the pain of rheumatoid arthritis without altering actual inflammation. However, the mixture of statistically significant and insignificant results indicates that a larger trial is necessary to factor out "statistical noise."
On average, participants in all groups showed improvement over the 6 months of the study. Participants in the treatment groups, especially Group 1, showed a trend toward greater improvement; however, the differences between real treatment and sham or no treatment failed to reach statistical significance in most measures. This outcome suggests that magnetic mattress pads might be helpful for fibromyalgia, but a larger study would be necessary to identify benefits.
Pulsed Electromagnetic Field Therapy (PEMF)
Pulsed electromagnetic field therapy (PEMF) is quite distinct from magnet therapy itself. (The term “electromagnetic field” does not, in this case, refer to magnetism in the ordinary sense.) Nonetheless, for historical reasons, it is often classified together with true magnetic therapies. Because of that, we discuss it here.
Bone has a remarkable capacity to heal from injury. In some cases, though, the broken ends do not join, called non-union fractures. PEMF therapy has been used to stimulate bone repair in non-union and other fractures since the 1970s; this is a relatively accepted use and will not be discussed here. More controversially, PEMF has shown promise for osteoarthritis, stress incontinence, and possibly other conditions as well.
The results showed that one session of magnetic stimulation significantly reduced episodes of urinary leakage over the following week, compared to placebo. In the treated group, 74% experienced significant improvement, compared to only 32% in the placebo group. Presumably, the high-intensity magnetic field used in this treatment created electrical currents in the pelvic muscles and nerves. This was confirmed by objective examination of 13 patients, which found that magnetic stimulation was in fact increasing the strength of closure at the exit from the bladder. However, there was one serious flaw in this study: it does not appear to have been double-blind. (For more information on why this is important, see Why Does This Database Rely on Double-blind Studies? ) Researchers apparently knew which participants were getting real treatment and which were not, and therefore might have unconsciously biased their observations to conform to their expectations. Thus, the promise of electromagnetic therapy for stress incontinence still needs to be validated in properly designed trials.
Electromagnetic Therapy: Repetitive Transcranial Magnetic Stimulation
Unlike PEMF, repetitive transcranial magnetic stimulation (rTMS) does in fact involve magnetic fields, and is, therefore, more closely related to standard magnet therapy. It involves applying low-frequency magnetic pulses to the brain. rTMS has been investigated for treating emotional illnesses and other conditions that originate in the brain. The results of preliminary studies have been generally promising.
How to Use Magnet Therapy
The following is a brief description of the use of magnet therapy. However, keep in mind that the current ways that magnets are used have yet to be fully evaluated by long-term clinical testing.
Types of Magnets
If you have decided you do wish to try magnet therapy, you will have to choose among many different types of magnets and magnetic devices on the market today. There are a number of theories on the size and type of magnets to use and where to apply them, based on the type of condition being treated and other factors. Because unipolar magnets have greater depth of magnetic field penetration, some researchers consider these more effective in treating deeper tissues. Conversely, it is considered that alternating-pole magnet devices might be more effective at stimulating surface tissue. Thus, it might be appropriate to use a unipolar high-gauss magnet for low back pain that originates deep in the tissue and an alternating-pole configuration for an injury closer to the surface, such as a wrist sprain. However, there is no meaningful scientific evidence to support these distinctions.
In addition, some practitioners hold that the north side of the magnet calms and the south side excites, and that using the correct side of the magnet is crucial. However, from a scientific perspective, it is difficult to see how there could be any difference between the two poles of the magnet in terms of the effect upon body tissue.
There is general consensus that the magnet should be placed as close to the affected part of the body as possible. This can be done by taping the magnet to the skin, slipping the magnet inside a bandage over the affected area, or using a wrap device that has magnets embedded in it.
Tape holding magnets to the body might irritate the skin; in addition, some research scientists and practitioners suspect that the body may accommodate to the magnetic field over time, thus reducing the therapeutic effect. In order to prevent both the irritation and the accommodation, practitioners usually recommend intermittent use, such as 5 days on, 2 days off; or 12 hours on, 12 hours off.
Magnetic Devices Available
Manufacturers make a wide range of magnetic devices. For treating large areas of the body, wraps and belts containing magnets are available. Wraps are specifically designed for the wrist, elbow, knee, ankle, neck, shoulder, and back, and are often made out of thermal material to have the added effect of warming the area. These wraps are often recommended in cases of injury and arthritis where heat feels better. Proponents of magnet therapy often recommend the use of magnetic mattress pads and mattresses for people with problems affecting several areas of the body, such as fibromyalgia or arthritis; they also recommend magnetic mattress pads for insomnia and fatigue.
Proponents of magnet therapy recommend magnetic foot insoles for people with diabetic peripheral neuropathy, leg aches and pains, circulatory problems of the lower extremities, or foot injuries and problems, and for people who stand all day.
Magnetic necklaces are said to be useful for neck and shoulder pain as well as for generalized aches and pains, and magnetic bracelets are advocated for wrist pain and general problems.
There are theoretical concerns that magnets might be risky for people with epilepsy. Similarly, until the physiological effects of magnet treatments are better understood, pregnant women should avoid them.
- Reviewer: EBSCO CAM Review Board
- Review Date: 08/2013 -
- Update Date: 00/81/2014 -