Magnet Therapy

Health Care Professional Information

Common Name

Biomagnetic therapy, electromagnetic field therapy

Brand Name

Magnetherapy Mattresses, Bioflex magnets, MagnaBloc

Clinical Summary

Alternative therapy available in clinics in Mexico, Germany, and elsewhere. Magnetic therapies are promoted to diagnose and treat cancer, HIV, psychiatric disorders, stress, multiple sclerosis, and infections, to increase energy, prolong life, and stimulate the immune system. Magnetic fields are administered by application of magnets to certain parts of the body, by magnetic field-generating machines, or with magnetic mattresses or blankets. Treatment can last minutes to weeks. Evidence supporting the use of magnetic therapies for the above conditions are limited. State consumer protection agencies and the FDA have prosecuted various marketers of magnetized devices and therapies, forcing them to halt unsubstantiated claims of health benefits.

In vitro studies show that static magnetic fields may modulate ion transport and related cell and neuronal activity (4) (7), but the physiological significance of these findings is unknown. No anti-cancer activity is demonstrated. Patients also use magnetized braces and mattresses to treat pain associated with fibromyalgia, diabetic neuropathy, sciatica, and arthritis. Clinical studies of these devices are small and flawed. Although some show improvements in pain associated with conditions such as diabetic neuropathy (23), fibromyalgia (2), and arthritis (19), results are often indistinguishable from placebo effects.
Body magnets are contraindicated in radiology and/or MR procedures. Patients with a cardiac pacemaker and pregnant women should also avoid use of magnetic devices. Magnetic Therapies have no role in the diagnosis or treatment of cancer.

Purported Uses
  • Antiaging
  • Arthritis
  • Cancer treatment
  • Circulatory disorders
  • Diabetic neuropathy
  • Fatigue
  • Fibromyalgia
  • HIV and AIDS
  • Immunostimulation
  • Infections
  • Inflammation
  • Insomnia
  • Multiple sclerosis
  • Muscle pain
  • Nausea and vomiting
  • Neuralgia
  • Pain
  • Peripheral neuropathy
  • Rheumatoid arthritis
  • Strength and stamina
  • Stress
  • Wound healing
Mechanism of Action

Marketers make varying unsubstantiated claims for how magnets work, such as: magnets “act upon the body's energy field,” or correct “magnetic field deficiency syndrome,” (1) a condition said to result from decreases in the earth's magnetic field over the past 1,000 years. It is purported that the positive (south) pole of the magnet has a “stress effect,” which interferes with metabolic functioning, produces acidity, reduces cellular oxygen supply, and encourages the replication of latent microorganisms. The negative (north) pole is said to have a “calming effect” and helps to normalize metabolic functioning, promote oxygenation, and treat neurological/psychiatric disorders. No evidence supports these claims, and no anti-cancer activity is seen for magnetic fields in laboratory or human studies. Most anecdotes of magnetic “healing” involve symptoms that may be psychosomatic, associated with stress, or subjective measures such as pain or depression (3).

Theoretically, static magnetic fields (SMFs) may alter ion flow, cellular potential, membrane configuration, ion pump activity, or neurotransmitter release (4). Most of the biological phenomena associated with SMFs may be caused by changes in cellular calcium (8). SMFs of 1,000-4,000 G are found to alter protein and enzyme structure and the kinetics of reactions involving free radicals (7) (9). Reduced action potential firing in cultured neurons and permeability changes in synthetic liposome vesicles are observed after application of a SMF (5). It may not be legitimate to extrapolate in vitro data, in which cells are directly exposed to magnetic fields, to their effect in a complex biological system. Moreover, many in vitro studies have not been replicated. Although some authors refer to documented effects of pulsed electromagnetic fields in attempting to explain a mechanism of action for static magnets, SMFs do not generate an electric field and therefore cannot confer the claimed physiologic effects (10). It is suggested that positive reports of magnet use reflect placebo effects.

Contraindications
  • Patients with a cardiac pacemaker and pregnant women should avoid use of magnetic devices.
Adverse Reactions

Regular use of low-intensity magnets appears to be safe. The World Health Organization reports that the available evidence indicates the absence of adverse effects on human health with exposure to magnetic fields up to 2 Tesla (20,000 G) (2)
Reported: Pain, nausea, and dizziness. Symptoms ceased upon removal of the magnets (15).
Case Report: Bullous pemphigoid associated with magnetic mattress use (4).

Herb-Drug Interactions

None known

Herb Lab Interactions

Body magnets interfere with radiology and/or MRI procedures.

Literature Summary and Critique

Segal NA, et al. Two configurations of static magnetic fields for treating rheumatoid arthritis of the knee: a double-blind clinical trial. Arch Phys Med Rehabil 2001;82:1453-60.A randomized, double-blind, controlled, multicenter trial evaluated magnetic pads in 64 patients with rheumatoid arthritis and persistent knee pain rated > 40/100 mm. Patients were randomized to wear MagnaBloc quadrapolar 1900 G magnets, measured to penetrate 5 cm into cadaveric tissue (n=38), or unipolar 720 G control device containing 1 functional and 3 sham magnets (n=26). Rheumatologist's global assessment of disease activity (R-GADA), erythrocyte sedimentation rate (ESR) and/or C-reactive protein, knee range of motion (ROM), examination for tenderness and swelling, patients' assessment of physical function, 100mm VAS score for pain, subjects' global assessment of disease activity (S-GADA), and the Modified Health Assessment Questionnaire (MHAQ) were measured at baseline, 1 hour, 1 day, and 1 week after placement of devices. Patients were asked to keep a pain diary. Both treatment arms showed a significant reduction in pain from baseline at 1 day and 1 week post-treatment (p<.0001). Though the MagnaBloc group showed a greater reduction in pain, the difference was not statistically significant (p<.23). S-GADA decreased significantly at 1 week in the MagnaBloc group (33%), while declining only 2% in controls. At 1 week, 68% of MagnaBloc patients and 27% of controls reported feeling better or much better (c2 = 10.64, p = .001). No other outcome changed significantly. No power analysis was performed to assess adequate sample size and length of intervention may be too short.

Collacott EA, et al. Bipolar permanent magnets for the treatment of chronic low back pain. JAMA 2000;283:1322-5.
A small, randomized, double-blind, placebo-controlled, crossover pilot study of the use of bipolar magnetic devices in 20 patients with low back pain. Subjects were randomized to receive one week of 282-330 G magnets and one week of sham, or vice versa, with one week washout between. Subjects applied devices 6 h/d, Mon/Wed/Fri. Outcomes measured were pre- and post-treatment pain on a Visual Analog Scale (VAS), Pain Rating Index (PRI) of the McGill Pain Questionnaire, and range of motion (ROM) of the lumbosacral spine. No significant differences were noted in any outcome for real or sham magnets; post-treatment pain declined slightly for both groups. Subjects reported no adverse effects. This study has been criticized for sex bias (95% of subjects male), selection bias (55% subjects were disabled, 85% were retired), and a weak intervention compared to other studies requiring 24 h/d use of stronger magnets.

Vallbona C, Hazlewood CF, Jurida G. Response of pain to static magnetic fields in postpolio patients: a double-blind pilot study. Arch Phys Med Rehabil 1997;78:1200-3.
A prospective double-blind study of bipolar 300-500 G Bioflex magnets versus sham in 50 patients with postpolio syndrome experiencing muscular or arthritic pain for at least 4 weeks. No significant differences in demographics or location of pain existed between study groups. However, a higher prevalence of muscular pain (compared to arthritic) and a higher female:male ratio were present in the experimental group. Only the most sensitive area of pain was evaluated per patient. Four different magnet sizes were used, depending on site of pain, applied to the skin with adhesive tape. Patients wore the device for 45 minutes; position or activity during this time was not monitored. Outcomes measured were McGill Pain Questionnaire and pain as assessed by palpation of a trigger point pre- and post-treatment. Both outcomes improved significantly for the treatment group compared to control, but pressure of palpation was not measured, so consistency is questionable. This study does not address the efficacy of long-term magnet use for chronic pain relief. Additional, larger studies are necessary and should control for magnet size between groups, female-male ratio, position during treatment, and source of pain.

Caselli MA, et al. Evaluation of magnetic foil and PPT Insoles in the treatment of heel pain. J Am Podiatr Med Assoc 1997;87:11-6.
Prospective, randomized evaluation of effect of insoles with or without magnetic foil on 34 otherwise healthy patients with medial plantar calcaneal heel pain. Primary outcome was foot function index, measured before and after 4 weeks of constant insole use. Eleven of 19 (58%) patients in the treatment group and 9 of 15 (60%) controls reported improvement, and no significant difference in the percentage improvement was measured. The authors conclude that the molded insole alone was effective in treating heel pain.

Dosage (Inside MSKCC Only)
This field is only visible to only OneMSK users.
References
  1. Hong CZ, et al. Magnetic necklace: its therapeutic effectiveness on neck and shoulder pain. Arch Phys Med Rehabil 1982;63:462-6.
  2. Colbert AP, et al. Magnetic mattress pad use in patients with fibromyalgia: a randomized double-blind pilot study. J Back Musculoskel Rehabil 1999;13:19-31.
  3. Macklis RM. Magnetic healing, quackery, and the debate about the health effects of electromagnetic fields. Ann Intern Med 1993;118:376-83.
  4. Burkhart CG, Burkhart CN. Are magnets effective for pain control? JAMA 2000;284:564-5.
  5. Man D, Man B, Plosker H. The influence of permanent magnetic field therapy on wound healing in suction lipectomy patients: a double-blind study. Plast Reconstr Surg 1999;104:2261-6.
  6. Szor JK, Topp R. Use of magnet therapy to heal an abdominal wound: a case study. Ostomy Wound Manage 1998;44:24-9.
  7. Repacholi MH, Greenebaum B. Interaction of static and extremely low frequency electric and magnetic fields with living systems: health effects and research needs. Bioelectromagnetics 1999;20:133-60.
  8. Flipo D, et al. Increased apoptosis, changes in intracellular Ca2+, and functional alterations in lymphocytes and macrophages after in vitro exposure to static magnetic field. J Toxicol Environ Health 1998;54:63-76.
  9. Atef MM, et al. Effects of a static magnetic field on haemoglobin structure and function. Int J Biol Macromol 1995;17:105-11.
  10. Rosen AD. Threshold and limits of magnetic field action at the presynaptic membrane. Biochim Biophys Acta 1994;1193:62-6.
  11. Liu S, et al. Magnetic disk applied on Neiguan point for prevention and treatment of cisplatin-induced nausea and vomiting. J Tradit Chin Med 1991;11:181-3.
  12. Weintraub MI. Chronic submaximal magnetic stimulation in peripheral neuropathy: is there a beneficial therapeutic relationship? Am J Pain Management 1998;8:12-6.
  13. McLean MJ, et al. Blockade of sensory neuron action potentials by a static magnetic field in the 10 mT range. Bioelectromagnetics 1995;16:20-32.
  14. Ohkubo C, Xu S. Acute effects of static magnetic fields on cutaneous microcirculation in rabbits. In Vivo 1997;11:221-6.
  15. Vallbona C, Richards T. Evolution of magnetic therapy from alternative to traditional medicine. Phys Med Rehabil Clin N Am 1999;10:729-54.
  16. Weintraub MI. Are magnets effective for pain control? JAMA 2000;284:565.
  17. Blechman AM. Discrepancy between claimed field flux density of some commercially available magnets and actual gaussmeter measurements. Altern Ther Health Med 2001;7:92-5.
  18. Carter R, et al. The effectiveness of magnet therapy for treatment of wrist pain attributed to carpal tunnel syndrome. J Fam Pract 2002;51:38-40.
  19. Segal NA, et al. Two configurations of static magnetic fields for treating rheumatoid arthritis of the knee: a double-blind clinical trial. Arch Phys Med Rehabil 2001;82:1453-60.
  20. Collacott EA, et al. Bipolar permanent magnets for the treatment of chronic low back pain. JAMA 2000;283:1322-5.
  21. Vallbona C, Hazlewood CF, Jurida G. Response of pain to static magnetic fields in postpolio patients: a double-blind pilot study. Arch Phys Med Rehabil 1997;78:1200-3.
  22. Caselli MA, et al. Evaluation of magnetic foil and PPT Insoles in the treatment of heel pain. J Am Podiatr Med Assoc 1997;87:11-6.
  23. Weintraub, MI et. al. Static magnetic field therapy for symptomatic diabetic neuropathy: a randomized, double-blind, placebo-controlled trial. Arch Phys Med Rehabil. 2003 May;84(5):736-46.

Consumer Information

How It Works

Bottom Line: Magnetic therapies have no role in the diagnosis or treatment of cancer. Clinical trials do not support the use of magnets to relieve pain.

The term “magnet therapy” encompasses practices as simple as wearing magnetized bracelets, to using magnetized mattresses, to therapy that involves large magnetic field-generating machinery. People have different theories for why magnets might have an effect upon the body, but they all generally claim that magnets act upon the body's molecules, ions, or “energy field” to correct disruptions. So far, there is no scientific support for this idea. Physics tell us that a static (unchanging) magnetic field will change the direction in which charged molecules (ions) move. Ions such as calcium and potassium are extremely important for cell signaling and nerve transmission in the body. However, even though laboratory experiments show that strong static magnetic fields (1000-4000 Gauss) might be able to alter the activity of ions in isolated cells, we still have no proof that these magnetic fields will do the same in the complex setting of the human body. or this will have a clinically meaningful effect. In addition, a group of researchers have tested several magnetized products and found that many did not deliver as high of a magnetic field as they claimed (much less than the amount needed to see effects in the above laboratory studies).

There is no scientific logic to the idea that magnets can cure cancer, and this effect has never been seen in humans. Most anecdotes of magnetic “healing” involve symptoms that may be psychosomatic, associated with stress, or subjective measures such as pain or depression.

Purported Uses
  • To relieve pain from arthritis, muscle strains, post-polio syndrome, or other conditions
    Only a few clinical trials have studied this use, and most have had serious design flaws. Many clinical trials have found no effect of magnets on pain. In the few clinical trials that have, design flaws and possible placebo effect have called the results into question.
  • To relieve pain, fatigue, and other symptoms of fibromyalgia
    One clinical trial supports this use.

There is no scientific evidence that magnet therapy is effective in treating the following conditions:

  • To reverse the effects of aging
  • To treat cancer
  • To improve fatigue
  • To treat HIV and AIDS
  • To stimulate the immune system
  • To treat infections
  • To reduce inflammation
  • To treat insomnia
  • To treat multiple sclerosis
  • To improve strength and stamina
  • To reduce stress
  • To improve circulation
  • To relieve nerve pain from conditions like diabetic neuropathy
  • To prevent nausea and vomiting
  • To improve wound healing
Research Evidence

Rheumatoid arthritis
Sixty-four patients with painful rheumatoid arthritis of the knee took part in a study of magnetic pads. The patients were randomly assigned to wear either (1) four MagnaBloc(R) 1900 Gauss magnets, or (2) one real magnet and three “sham” magnets, measuring 720 Gauss total. The magnets were tested beforehand to ensure that their magnetic field penetrated 5 cm into tissue. After one week of wearing the magnets, both groups reported a significant reduction in pain. People in the magnet group reported a greater improvement in symptoms, but there was no change in other measures of improvement, such as physician evaluation, range of motion, or inflammatory blood markers. These results do not support the use of magnets in treating an inflammatory disease such as rheumatoid arthritis, and it is possible that any improvements patients experienced were due to placebo effects.

Chronic low back pain
In 2000, the Journal of the American Medical Association published a report of a small clinical trial that did not support the use of magnets for treating chronic low back pain. Twenty people were given both real magnets (around 300 Gauss) and “sham” magnets, but were not told which were which. Half of the people wore the real magnets for two weeks, took a week off, then switched to the sham magnets, and the other half did the opposite. At the end of the study, people reported having less pain both while wearing the real magnets and while wearing the sham magnets. This indicates that the reduction in pain was due to a placebo effect. However, unlike other studies in which magnets were worn all day, in this study people used them only for six hours a day, Monday, Wednesday, and Friday.

Fibromyalgia
The use of magnetized mattress pads by women with fibromyalgia was studied in a small clinical trial. For 16 weeks, 13 women used unipolar magnetized mattress pads (about 1100 Gauss) and 12 used non-magnetized mattress pads. The women sleeping on magnetized mattress pads reported greatly improved pain, sleep problems, fatigue, and quality of life compared to the women using sham mattress pads. However, the two groups were not totally equal: women who were given sham mattress pads, on average, were heavier (the magnetic field may have not penetrated as deeply) and had higher use of anti-anxiety and pain medications, indicating that they probably had more severe pain to begin with. For these reasons, the results of this study are not very strong.

Postpolio syndrome
A clinical trial studied the use of bipolar 300-500 Gauss Bioflex(R) magnets in 50 patients with painful postpolio syndrome. Half of the patients were given real magnets to apply to their most painful body part, while the other half were given “sham” magnets. After 45 minutes, doctors measured the amount of pain in that body part by palpating it and with a questionnaire. People using the real magnets reported a greater reduction in pain, but there are a few problems with these findings. There were more people with muscle pain, compared to arthritis pain, in the group that used real magnets. This is important because the nature of these two types of pain may be different. Also, because many different sized magnets were used to treat many different body parts, this study lacks consistency.

Foot pain:
Thirty-four otherwise healthy patients with inner heel pain enrolled in a study of magnetized insoles. Half of the patients were given magnetized insoles, while the other half used regular, non-magnetized insoles. After four weeks of constantly using the insoles, about 60% of both groups reported improvements in heel pain. This indicates that the improvements may have been due to the insoles, not the magnets.

Patient Warnings
  • Magnetic bracelets, necklaces, braces, or other devices should be removed from the body before getting an x-ray or MRI.
  • Various state consumer protection agencies and the F.D.A. have prosecuted marketers of magnetized devices and therapies, forcing them to stop making unsupported claims of health benefits.
Do Not Take If
  • You are pregnant.
  • You have a cardiac pacemaker.
Side Effects
  • Regular use of low-intensity magnets is relatively safe. The World Health Organization reports that magnetic fields up to 2 Tesla (20,000 G) appear to be safe.
  • Pain
  • Nausea
  • Dizziness
  • Case Report: One patient using a magnetic mattress developed bullous pemphigoid (a blistering skin condition)
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