Probably one of the largest contemporary trends in the therapeutic world is the use of magnetic therapy. However, it is also one of the least researched modalities, and has very little sound explanation for it’s effectiveness. Winning over its clientele with testimonials by everyone from doctors to elite athletes, magnets are making a place for themselves in the health and therapeutic fields. This is accomplished by utilizing many different marketing strategies and very little research. “The trend is so lucrative, athletes are adding brand-name magnets to their list of endorsements” (Ruibal, p. 3C).
This method of rehabilitation and treatment dates back thousands of years to when they were used by Greek, Persian and Chinese physicians. These physicians used magnetic rocks, now called lodestones, to treat conditions such as gout and muscle spasm (Borsa, p. 150; Meyer 1997). In the early 1500s, Paracelsus, a physician in Greece, thought that magnets were effective therapeutically due to their ability to attract iron. He hypothesized that because of this capability, they would also be able to leach diseases from the body. However, Paracelsus was also very aware of the tendency the human mind has in playing a role in the healing process:
“The spirit of the master, the imagination is the instrument, the body is the plastic material. The moral atmosphere surrounding the patient can have a strong influence on the course of the disease. It is not a curse or a blessing that works, but the idea. The imagination produces the effect” (Livingston, p. 25).
This role imagination plays, known as the placebo effect, is a true thorn in the side of magnetic therapy as a practice. And this is where the debate lies: between true physiological efficacy and the placebo effect. The question that should be posed to manufacturers, advertisers, and customers of magnetic products is whether or not magnetic therapy is truly effective. Magnetic therapy could indeed be a useful rehabilitation technique but is still only a theory due to a lack of experimental evidence (Borsa, p. 150; Livingston p. 26; Vallbona et al. p. 1204). This is often overlooked however. The use of testimonials in the marketing and advertising for these magnets makes it difficult for the common consumer to view this type of therapy objectively.
One aspect that is understood, however, are the effect magnetic fields have on our bodies during everyday life. We are constantly being exposed to magnetic fields. Microwaves, power lines, radio waves, refrigerators: these all give off magnetic charges (CSA, 1994; Barnothy p. 123). The earth is surrounded by a magnetic field, which is the reason for the North and South poles (Leonard, 861).
Our bodies too have magnetic fields. According to the Gale Encyclopedia of Medicine, magnetic fields from the external environment enter the body easily because it is approximately 70% water. After penetrating into the tissues, a change in the alignment of the body’s electromagnetic fields and an interaction with acupuncture points and meridians on the body occurs (Robinson, 1846). Magnetic fields also aids the following functions: cell division and replacement, blood circulation and hemoglobin saturation, flushing of deposits that line the walls of blood vessels and improved conduction of nerve impulses, thus improving brain function (Meyer, 1997; Livingston, 1999). But, because the human body is complex and the physics of electromagnetic fields is complex, the interactions of the two are also increasingly complex and still not well understood (CSA, 1999).
However, there is some research that says certain injuries or abnormalities that occur in the body registers as a positive magnetic field. This positive electromagnetic signal is carried to the brain, and responds by sending back a negative magnetic field to the injured site to aid in the healing process. The human body has a natural tendency to better perform and succeed in this negatively charged environment. These charges applied cause the body’s water, because of its diamagnetic properties, to have a repellency affect. In response to this applied magnetic field, the electrons in the water molecules make slight adjustments in their motions to repel.
Like water, blood too has diamagnetic properties, and is animated and repelled by magnetic fields. There has been evidence, shown in a study by Dr. Hackel (of Michigan State University) et al, that erythrocytes respond to magnetic fields in that they “are aligned and perhaps even displaced by the action of macroscopic magnetic fields.” Such motion causes active antigen sites on the cell surface to take up positions that are favorable for reactions with antibodies (p. 227). This helps with reduction of inflammation and detoxification.
Other noted affects are control of cell division and DNA, local pH regulated back to alkalinity, high oxidation levels promoting ATP production, increased secretion of growth hormone and melatonin and enhancement of enzyme activity (Barnothy, pp. 134-137).
Like most other situations in the body, sometimes the brain does not send an adequate amount of negative charge to the site of the anomaly because your body has a limited energy capacity for generating magnetic fields. Your body cannot come up with enough gauss strength to heal certain maladies with the negative charge (Livingston, 1999).
By taking all these factors into consideration, it would seem accurate to say that magnetic therapy could in fact be a beneficial modality in reducing pain and swelling in the body’s tissues.They could even accelerate the healing process, due to the fact that negatively charged magnet can pick up where the brain left off. There have been studies that show magnetic therapy is successful, perhaps due to that theory.
One example of this research is an experiment done by Baylor’s Institute for Rehabilitation Research in Houston, Texas. Before the magnetic therapy, patients graded their pain on a scale of 0 to 10 (10 being the worst pain). The magnet (or ineffective magnet, depending on the group) was placed over the trigger point of the painful area. The researchers used magnets with an intensity of 300 to 500 gauss (G), and were 1.75 cm by 0.50 cm wide, and 1.5 mm thick dimensionally.
After a 45-minute period wearing the magnet (or placebo), they graded their pain a second time. Patients with the placebo magnet averaged a starting pain of 9.5 and ended with a pain of 8.4 (+/- 1.6 points, p *0.005). Patients with the active magnet averaged a starting pain of 9.6 and ended with a pain of 4.4 (+/- 3.1, p *0.0001). This double-blind study successfully showed that there was a significant reduction of pain after a 45-minute period of magnet use. The patients in the active-device group reported a pain score decrease by 76%, while there was only a 19% decrease in pain score for the placebo-device group.
“We cannot explain the significant and quick pain relief reported by our study patients. The effect could result from a local or direct change in pain receptors, but it is also possible that there was an indirect central response in pain perception at the cerebral cortical or subcortical areas, or a change in the release of enkephalins at the reticular system. If the fields have an impact on the subcortical level of the brain, it is possible that the application of one magnetic device in one painful area may benefit to a greater or lesser extent the pain elicited in other trigger points. This is an issue that requires further study” (Vallbona, et al. p. 1202).
The researchers of the Baylor study also decided that there were specific issues that need to be explored through new studies. Some of these points that are still yet to be understood include dose-response to pain relief, the effect of the simultaneous application of magnets on several pain trigger areas, and the possible difference of effect of various sizes and shapes of a magnetized device. Lastly, and probably one of the biggest issue overall, is the issue of whether or not magnetic therapy is cost effective, as opposed to the traditional pharmacological or physical therapy modalities and their effect on pain management (Vallbona, et al. p. 1203).
Paul Borsa of Oregon State University did another important study on the effects of magnets. His research contends the use of flexible magnets on pain production. He and his colleagues performed a single blind pilot study using repeated measures. They tested recovery time after the muscle microinjury and pain perception.
The experimental group received a 700 G flexible magnet, which was constructed from silicon rubber and high grade steel, and had the properties of a static magnetic field. These magnets were 8 cm by 5 cm and 3 mm thick (slightly larger than those from the Baylor study due to the size of the treated area). Patients wore the magnet after participating in exercise-induced, concentric-eccentric muscle soreness protocol of the biceps brachii, and came to have their pain perception, range of motion, and static force production (the three primary dependent measures) measured after 24, 48, and 72 hours of wearing the device. A visual analog scale (0-10), like that of the Baylor study, assessed pain perception, range of motion was evaluated using a goniometer on elbow flexion and extension, and static force production was measured using an isokinetic testing device (Borsa, pp. 152-153).
The results were not statistically significant in pretreatment versus posttreament data. Pain perception, range of motion, and static force production all had a mean p-value of less than 0.05. Borsa and company give a reason for their claim that the results are insignificant; that it is a matter of a lack of thermal effect due to the low strength of the magnetic field applied (p. 153).
While energy transmitted from the magnets is reported to produce both thermal and non-thermal physiological effects within injured soft tissue (Livingston, 1999; Borsa, p. 153) is possible, in order to get a significant thermal effect from the magnetic field, the strength must be between 150 G and 15,000 G. Since most commercially available flexible magnets have strengths below 1000 G (Borsa, pp. 153-4), they would naturally be a significantly lower gain of thermal heat due to their lack of magnetic power.
This thermal heat is a result of Hall voltage, and is caused by a magnetic field of sufficient strength that passes through a conductive fluid such as blood, produces an electromotive force (the Hall voltage). A significant amount of this voltage can cause blood ions to become active and dynamic, colliding with each other, and thus producing heat and vasodilation. This is called the magnetohydrodynamic effect (see Fig. 1). This effect has the capability to mimic heating agents used therapeutically, but it is hard to attain that level of heat due to a lack of approval by the Food and Drug Administration to use such high powered magnets (Borsa, p. 153; Barnothy, p. 128; Meyer, 1997).
However, this does not seem concordant with the Baylor study. And, this discrepancy is actually something fairly consistent between findings in magnetic research. In this situation, it could merely be a matter of different magnets used for different ailments. In the Baylor study, the magnets were used on postpolio patients over both muscular and arthritic pain, while in Borsa’s study, the magnets were worn over muscular microinjuries for a longer period of time with greater potency (in gauss). However, this is not a matter of different studies using different variables.
These two studies actually represent magnetic therapy research well in that most of the conclusions are fairly inconsistent with each other. Since there is not very much experimental evidence and no outstanding conclusion that is apparent either way, it seems that this type of research should become more important as more products are sold to uninformed customers. Customers should pay attention to the fact that the FDA has not yet approved magnetic therapy. Also, “U.S. consumers will spend more than $500 million this year on magnetic pads, bracelets, shoe inserts, back wraps, and seat cushions” without really knowing their products true potency or repercussion (Ruibal, p. 3C).
“The most prudent way of understanding the effect of static magnetic fields on biologic tissue is through the controlled experimentation” (Borsa, 154). Therefore, more research is needed in order to assure that the uses of magnets are cost-effective, safe, and a useful therapeutic modality.
Barnothy, Madeleine F. (1964). Wound healing and tissue regeneration. In Madeleine Barnothy (Ed.), The Biological Effects of Magnetic Fields, pp. 120-141. New York: Plenum Press.
Borsa, Paul A., PhD, ATC/R & Ligget, Charles L., MS, ATC. (June, 1998).Flexible magnets are not effective in decreasing pain perception and recovery time after muscle microinjury. Journal of Athletic Training, Vol 33. Pp. 150-155.
Council of Scientific Affairs report (CSA). (December 1994). Report 7 of the Council on Scientific Affairs: Effects of Electric and Magnetic Fields. online Available: www.ama-assn.org/med-sci/csa/1994/rpt6au94.htm (Nov. 8, 1999).
Hackel, E.; Smith, A.E.; & Montgomery, D.J. (1964) Agglutination of human erythrocytes. In Madeleine Barnothy (Ed.), The Biological Effects of Magnetic Fields, pp.218-228. New York: Plenum Press.
Larson, Leonard. (1971). In Encyclopedia of Sport Sciences and Medicine (pp. 861-862). New York: The MacMillan Company.
Livingston, James D. (1998) Magnetic therapy: a plausible attraction? Skeptical Inquirer, v2 2, n4. pp. 25-27.
Meyer, Martin (1997). Magnetics for Healthy Healing. online. Available: www.hre.com/totalhealth/magnh.html (Nov. 8, 1999).
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Ruibal, Sal. (1997, Aug. 20). Ironclad cures for pain? Athletes put their faith in power of magnets. USA Today, Final Edition, p. 3C.
Vallbona, Carlos, MD; Hazelwood, Carlton F, PhD & Jurida, Gabo, MD. Response of Pain to Static Magnetic Fields in Postpolio Patients: A Double-blind Pilot Study. Arch Physiological Medicine Rehabilitation, 1997; vol. 78. pp. 1200-3.