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Rapid Responses: Rapid Responses published:
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Magnet therapy: Non-clinical claims are also questionable
- G James Rubin, Simon Wessely (6 January 2006)
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Magnetic therapy not necessarily far-fetched
- James TH Teo (7 January 2006)
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Magnet Therapy: A lack of understanding of the physical principles of magnetism
- Jon Dobson (7 January 2006)
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Magnetic therapy
- John M Davies (9 January 2006)
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Re: Magnetic therapy not necessarily far-fetched
- Anthony T. Barker (9 January 2006)
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Mode of action of magnets for treating some pain
- John N Walters (9 January 2006)
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Magnet Therapy-the real truth
- michael i. weintraub (10 January 2006)
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Research and history are poles apart: But aren’t we attracted to Magnetic therapy?
- Mr Anil Joshi, Dr Pavan Kumar BC Raju, Clinical Attachment. Department of Anaesthetics, Hope Hospital, Salford, M6 8WH (10 January 2006)
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Extraordinary Editorial
- Timothy N Harlow (10 January 2006)
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Misleading criticism
- Ray Padfield-Krala (11 January 2006)
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Animal studies in magnet therapy are not subject to placebo
- Roger Coghill (11 January 2006)
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Blinding and sham controls with magnet therapy trials
- Agatha P Colbert (15 January 2006)
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Misleading Editorial
- Marko Markov (17 January 2006)
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Therapeutic effects of magnetic fields
- Carlton F. Hazlewood (21 January 2006)
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Non-Evidence-based Editorial
- Nyjon K Eccles (27 January 2006)
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Replies to Responders
- Leonard Finegold, Bruce L. Flamm (31 January 2006)
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G James Rubin, Research Fellow King’s College London, Weston Education Centre, Cutcombe Road, London SE5 9RJ., Simon Wessely
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Editor – Finegold and Flamm1 rightly highlight the lack of good quality evidence for the alleged healing powers of the magnetic products currently on sale to the public. As they note, the very fact that these devices are magnetic can make it difficult to perform double-blind trials of their efficacy. However, this does not prevent us from testing the other, non- clinical but equally impressive, claims that are sometimes made for them. For instance, we recently conducted a randomised controlled trial of a magnetic product supposedly able to improve the flavour of cheap wine2. The study cost less than £70 to conduct, took two evenings to run, and was easy to double-blind. Wine drinkers will be disappointed to learn that we were unable to verify the manufacturer’s claims. Other magnetic devices are sold on the basis that they can cut pollution from cars, reduce your domestic gas bill, and even rid your dog of fleas. Many of these are made by the same companies that produce the bracelets, insoles and mattresses that Finegold and Flamm refer to. Good-quality double-blind randomised controlled trials to test these non-therapeutic claims are not beyond the manufacturers’ means. That such evidence is not provided might give us additional pause for thought. 1. Finegold L, Flamm BL Magnet therapy. Extraordinary claims, but no proved benefits BMJ 2006;332:4. 2. Rubin GJ, Hahn G, Allberry E, Innes R, Wessely S. Drawn to drink. A double-blind randomised cross-over trial of the effects of magnets on the taste of cheap red wine. J Wine Research 2005;16:65-69. Competing interests: None declared |
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James TH Teo, Clinical Research Fellow Sobell Department of Motor Neuroscience, Institute of Neurology, Queen Square , London WC1N BG
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In response to your editorial (BMJ, 7 Jan 2006), I would like to add that not all magnetic devices are equally non-efficacious. Magnetic fields from bracelets and such may have little effect on human tissue but it would be wrong to discount all effect on human tissue, 'even theoretically'.
There is a strong research literature using transcranial magnetic stimulation (TMS) to induce neuronal firing in the brain and spinal cord. (Ref 1 & 2) Small pilots studies have been done using this technique in stroke (Ref 3), Parkinsons disease (Ref 4), depression (Ref 5) and many other neurological and psychiatric conditions. A neglect-like syndrome can be transiently induced in health subjects (Ref 6) shedding light on physiological and cognitive processes.While no large clinical trials have been done yet, it is vital that not all magnetic therapy should be discounted.
------------------------------------------------------ Competing interests: The author is a clinical researcher working in the field of neurophysiology |
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Jon Dobson, Professor of Biophysics Keele University
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Firstly, I would like to thank Professors Finegold and Flamm for their editorial. I have been involved in biomagnetics and iron biomineralization research for about 15 years and I have been approached many times by people claiming benefits from magnets, thinking that my research is synonymous with magnet therapy. I will now be able to steer them to a short and insightful examination of the field. While I try to remain open-minded, it seems that most of the companies that sell magnets for therapeutic purposes have a lack of understanding of the physics of magnetism. A major part of my research involves attaching therapeutic drugs and genes to magnetic nanoparticles and guiding them to specific sites in the body. One of the greatest difficulties facing this work is the fact that the magnetic field generated by even the strongest rare earth magnets drops off so rapidly that if the site of injury or therapeutic target is more than a couple of centimeters or so below the surface, the field strength is not strong enough to attract even highly magnetized nanoparticles. On the website for World of Magnets (one of the respondents interviewed by the BBC in their news story on this article), they claim to get around this problem by recommending that the patient drink "magnetized" water. Pure water, like tissue in the human body, is diamagnetic - which means that it retains no magnetization in the absence of a magnetic field. The website claims that the by drinking magnetized water, "the magnetism travels into the stomach and is absorbed into the blood steam through the bowel wall." It is claimed that this concept of magnetized water is "scientifically proven and clinically tested". It amazes me that a product is allowed to be advertised like this. Hopefully the publicity stirred up by this article will lead to proper, scientific evaluation of some of the claims of magnet therapy. Or, at the very least, save a few people some of their hard-earned money. Competing interests: None declared |
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John M Davies, Retired Consultant Paediatrician DN33 3NA
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Can I remind the Editor and readers that Wolfgang Amadeus Mozart, Lorenzo da Ponte, Doctor Mesmer and Despina all knew the therapeutic power of a magnet as demonstrated in one of the world's greatest operatic masterpieces, "Cosi fan tutte" Act I Scene II at the Vienna, Burgtheater, in 1790 and throughout the world subsequently. John Martin Davies MA MRCP MRCS DCH etc Competing interests: None declared |
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Anthony T. Barker, Consultant Clinical Scientist and Associate Professor Department of Medical Physics, Royal Hallamshire Hospital, Sheffield S10 2JF
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Dr. Teo is quite correct in stating that Transcranial Magnetic Stimulation (TMS) has demonstrable and real effects on the body. However it is important to distinguish these effects from those claimed by proponents of permanent magnet therapies. TMS involves the local application of strong magnetic field pulses, of the order of one Tesla, with risetimes of order 100 microseconds. These induce electric fields and currents in the body, by Faradays' principle of Electromagnetic Induction, which are sufficiently large to approach or exceed the threshold for neuromuscular depolarisation. This can readily be demonstrated by putting a stimulating coil over the motor cortex, firing the stimulator, and observing the resultant mechanical twitch and electrophysiological response from (say) a hand muscle (1). The underlying principles by which this occurs are well undestood and several thousand papers have now described diagnostic and possible therapeutic applications of TMS. Permanent magnet therapies, by definition, do not involve time- varying magnetic fields. Hence any biological effects they have, if they exist, must be based on a totally different physics principle. Claims for their efficacy are widespread, reliable scientific evidence is scant or non-existent and the claimed physiological effects, such as vasodilation, are both unsubstantiated and contrary to the experiences of those who work with or experience strong magnetic fields in their everyday lives. Reference (1) Barker AT, Jalinous R and Freeston IL; Non-invasive stimulation of the human motor cortex. Lancet, 1985, 1106-1107 Competing interests: None declared |
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John N Walters, GP Keogh Barracks
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In general practice I have been struck over the years by the numbers of patients whose osteoarthritic pain is exacerbated by changes in the weather - some can reliably predict meteorological events from their aching bones. On further questioning and careful examination the pain is actually coming from bone immediately adjacent to the affected joint, in the area where there is presumably an abnormal microscopic and macroscopic structure produced by the OA. Similar effects are seen at old and long healed fracture sites. My own theory, for which I have no supporting evidence, is that this is in fact an electromagnetic phenomenum, and occurs for the same reason that some radio transmissions are adversely affected by weather fronts. I understand that this is due to the rapid movement of charged particles in the atmosphere interacting with the Earth's magnetic field to produce electromagnetic waves. This could be "received" by the crystalline mineral structure of the abnormal bone and produce micro-electrical currents. I have tried using magnets to treat this osteoarthritic/bone pain, sometimes with good results. On the basis of this hypothesis I would not expect it to work in purely soft tissue pain, and have not tried it for this. My guess is that the magnetic field when in close proximity to the painful joint is somehow blocking the electromagnetic fields producing the bone pain. This relatively simple hypothesis would explain the findings in the recent BMJ article where magnets helped with the pain of OA hip and knee joints. Competing interests: None declared |
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michael i. weintraub, Clinical Professor of Neurology and Internal Medicine, New York Medical College 325 S. Highland Avenue, Briarcliff, NY, USA 10510
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MAGNET THERAPY-THE REAL TRUTH Man’s fascination with magnetism’s invisible forces and presumed efficacy can be traced back more than 4,000 years. This has subsequently created combinations of science, pseudoscience, quackery, sensationalism, and controversy. The recent editorial of Finegold and Flamm was informative yet disappointing.1 It is important to be skeptical about any new treatment and claims and I totally agree with the authors that there have been extraordinary claims made primarily for profit. However, I have specific concerns and reservations regarding many of their statements. It is obviously easy to criticize but these authors appear to have an agenda casting doubt on efficacy arriving at preconceived conclusions based on selective citations from the literature. Magnets are not magical! Thus, an accurate appraisal of the potential biological effects of static magnets requires a rigorous randomized, double-blind, placebo-controlled protocol, a homogenous cohort, understanding of the dosimetry, measurements of penetration of magnetic flux lines, sufficient duration of contact and exposure as well as standardized subjective and objective tests to arrive at a meaningful conclusion. Colbert2 has reviewed 22 therapeutic trials published in the American literature from 1982-2002 with clinical improvement in 15 studies and 7 had limited or no benefit. Successful trials utilized unipolar, bipolar, quadripolar and triangular magnetic arrays. The magnetic field strengths varied from 68 G - 2,000 G with application exposure varying from 45 minutes to constant wearing for four months. Thus, the optimum treatment duration, strength of the devices as well as the optimal polarity have yet to be established. Additionally, Blechman and coworkers3 found a significant number of errors in manufacturers’ claims who were selling devices to the public. Many studies are doomed to failure because of methodological protocol flaws with inadequate dosimetry, inadequate duration of application as well as a lack of a homogenous cohort. Finegold and Flamm decided to emphasize these poorly performed studies to arrive at their conclusion. Does anyone really believe that applying magnetic devices to the back for a few hours per week in individuals who suffer from chronic problems dating 20 years is going to make a difference?4 If the authors were to critically review Carter’s and coworkers’ study5 on wrist pain attributed to carpal tunnel syndrome (CTS) they would find numerous flaws from lack of neurological and electrodiagnostic confirmation of the diagnosis, use of 1,000 G unipolar static magnet with five magnetic pads glued together applied for 45 minutes with no specific testing by gaussmeter to determine the presence of cancellation at surface by opposing poles, magnetic flux density into tissues, etc. Introducing recall bias by use of a postcard two weeks later as well as absence of IRB review of protocol are also serious flaws. If Finegold and Flamm wanted to be credible, they should have quoted the positive study by Weintraub6 with a placebo-controlled, constant 24/7 application of a 350 G magnetic wrist wrap with 20 mm penetration for two months. Reduction in neuropathic pain and improvement in motor distal latencies were noted. It is puzzling that the authors cited my skeptical approach and pilot study in 1999 7 but not the definitive nationwide study of 375 patients with diabetic peripheral neuropathy published in 2003.8 This was a randomized, placebo-controlled, double-blind study from 48 centers with constant 24/7 treatment of magnetic foot insoles for four months (350 Gauss with 20 mm penetration measured by Lakeshore gaussmeter). Statistical reduction in neuropathic pain scores and improvement in quality of life was noted that was equal or superior to current pharmacotherapy and only cost less than $100. We also looked at patient unblinding since it is impossible to blind a magnet as well as breaking the code and this was not an issue. Thus, the fact that these authors have not included up to date information has weakened their conclusions. Finegold and Flamm also make erroneous statements about MRI and the human body’s response to magnetic fields. They conveniently overlook or are unaware that in 1979, the FDA approved time-varying magnetic fields (pulsed electromagnetic field therapy, PEMF) to be used in healing non- union fractures. 2,9 This treatment is used world-wide with hundreds of thousands of applications and a success rate greater than 80%. PEMF has also been demonstrated to be effective in other musculoskeletal painful disorders.2 These authors also make bold and erroneous statements regarding MRI and human tissue. Most biological tissues are weakly magnetic and diamagnetic. MRI generates magnetic fields and Radio Frequency (RF) energy which directly or by fringe effects induce electric fields within tissues (Faraday’s Law, Lenz Law)2,9 Although not harmful, some individuals experience sensory changes.10 With the recent introduction of a powerful 3 Tesla unit in our community, we reviewed 494 consecutive cases using 3 T, 1.5 T, and 0.7 T in five units and surprisingly found 18% of subjects experiencing new symptoms, i.e. magnetophosphenes, metallic taste in mouth/tongue, vertigo/dizziness and pain changes. Although not harmful and transitory, these strong fields produced presumed intracellular changes in the retinal rods, electrolysis of metallic chemicals in teeth fillings, magnetohydrodynamic forces within the labyrinth and otolith and ion/ligand stimulation respectively.11 Based upon their statements, the authors are clearly unaware of Transcranial Magnetic Stimulation (TMS) that creates a time-varying magnetic field over the surface of the head and depolarizes underlying brain tissue with induction of electric currents in the tissues. There has been widespread medical applications of TMS for depression, epilepsy, stroke, Parkinson’s disease, aphasia, tremor, etc.2,12 Thus, the study of magnetic fields has evolved from a medical curiosity into significant medical applications. While it may be premature to either advocate or reject the use of static magnetic fields, there is no doubt that PEMF and TMS can influence biological functions and serve as a diagnostic and therapeutic intervention. While the debate continues regarding efficacy of static magnetic fields, the scientific community must demand rigorous randomized, double-blind, placebo- controlled trials with known dosimetry and magnetic flux penetration, homogenous cohorts, avoidance of financial conflicts, etc. Lastly, Journals need to act more responsibly13 in accepting and rejecting papers with poorly developed protocols that are doomed to failure especially without IRB. Similarly, authors writing editorials need to be knowledgeable about the current literature and refrain from making unsubstantiated and erroneous conclusions. Respectfully submitted, Michael I. Weintraub, M.D., F.A.C.P., F.A.A.N.
REFERENCES: 1. Finegold L, Flamm BL. Magnet therapy. Extraordinary claims, but no proved benefits. BMJ 2006; 332:1. 2. Weintraub MI: Magnetotherapy: Historical background with a stimulating future. Critical Reviews in Physical and Rehab Medicine 2004; 16: 95-108. 3. Blechman AM, Oz MC, Nair V, Ting W. Discrepancy between claimed field flux density of some commercially available magnets and actual gaussmeter measurements. Alt Ther 2001; 7: 92-95. 4. Collacott EA, Zimmerman JT, White DW, Rindone JP. Bipolar permanent magnets for the treatment of chronic low back pain. JAMA 1999; 283: 1322- 25. 5. Carter R, Hall T, Aspy CB, Mold J. The effectiveness of magnetic therapy for treatment of wrist pain attributed to carpal tunnel syndrome. J Family Practice 2002; 51: 38-40. 6. Weintraub, MI. Neuromagnetic treatment of pain in refractory carpal tunnel syndrome: an electrophysiological and placebo analysis. J Back Musculoskel Rehab 2002; 15: 77-81. 7. Weintraub, MI, Magnetic bio-stimulation in painful diabetic peripheral neuropathy: a novel intervention. A randomized, double-placebo crossover study. Amer J Pain Mgt 1999; 9: 8-17. 8. Weintraub MI, Wolfe GI, Barohn RA, et al. Static magnetic field therapy for symptomatic diabetic neuropathy: a randomized, double-blind, placebo-controlled trial. Arch Phys Med Rehab 2003; 84: 736-746. 9. Bioelectromagnetic Medicine: Rosch PJ, Markov MS (eds). Marcel Dekker, Inc. New York 2004. 10. Chakeres DW, Dee Vocht F. Static magnetic field effects on human subjects related to Magnetic Resonance Imaging (MRI) systems. Progress in Biophysics and Molecular Biology 2005; 87: 255-265. 11. Weintraub, MI, Khoury A, Cole SP. Biologic effects of induced current by 3 Tesla (T) MRI imaging. Comparison with traditional 1.5 Tesla and 0.7 Tesla in 494 consecutive cases. (Abstract submitted to 58 Annual Meeting of American Academy of Neurology, April 1-8, 2006. Decision for acceptance will be made in February.) 12. Handbook of transcranial magnetic stimulation. Pascual-Leone A, Wasserman EM, Davey NJ (eds) Oxford University Press, London, UK 2002. 13. Weintraub, MI. Magnetic insoles. Mayo Clin Proc 2006; 81: 2. Competing interests: None declared |
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Mr Anil Joshi, Senior House Officer Addenbrooke's Hospital, Cambridge, CB2 2QQ, Dr Pavan Kumar BC Raju, Clinical Attachment. Department of Anaesthetics, Hope Hospital, Salford, M6 8WH
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The article “Magnetic therapy: extraordinary claims but no proved benefits” published in the BMJ 6/01/2006 by authors Leonard Finegold and Bruce L Flamm highlights a few facts on the validity of therapeutic efficacy of magnetic therapy. The points summarised by the authors were based on the facts that there are no randomised controlled trials with proper blinding to rule out any bias, no scientific research directed towards the mechanism of action of electromagnetic field on human physiology and it burning a big hole in the pockets of the customers. Although some of the arguments were logical, they were only partially true. In a recent randomised controlled trial by Hinman et al[1], forty- three patients with chronic knee pain were recruited from the clinics or those who volunteered to participate. Both the controls and cases were similar with respect to gender, age and duration of arthritis. There was a statistically significant treatment effect with marked improvement in terms of pain (P= .002), physical function (P= .001) and gait speed (P= .042) than with subjects who just wore placebos. Furthermore, these chronic painful conditions have a serious impact on the psychological aspect which we normally tend to ignore. Hence, any kind of relief would play a positive role on patient’s comfort, which is actually one of the goals of our Health Care. So, if a magnet is doing this job, then why not? Historical evidences sometimes though difficult to prove cannot be discarded outright. The Greeks, Egyptians and Chinese all recorded healing powers associated with earth’s magnetic field. Progress in research has been made in this field in two wide areas. One is the pulsed electromagnetic field in which scientific evidences point towards increased healing in damaged muscles and skeleton relieving pain, reducing inflammation, increasing vascularisation and stimulating proliferation of chondroblasts, fibroblasts and osteoblasts[2]. The other area is the static magnetic fields (SMF) in which experiments have been mainly in animals have demonstrated increased bone density, faster bone repair and decreased joint inflammation. Yan QC et al[3], in an experimental study on rats’ femur looked into the effects of SMF. They inserted magnetised and unmagnetised samarium cobalt transcortically into the rats’ femur. The result revealed that the femurs adjacent to magnetized specimens had significantly higher bone mineral density (BMD) and calcium content than those adjacent to the unmagnetized specimen (p < 0.01). There are also various studies on the effects of magnetic therapy. Weintraub MI[4], et al demonstrated improvement with pulsed electromagnetic field (PEMF) on patients with neuropathic pain in peripheral neuritis. Studies have also shown the effectiveness of magnetic therapy on multiple sclerosis[5], Parkinson’s and Alzheimer’s disease. Any kind of relief in such chronic illnesses has a dual impact on the patient, both physical and psychological improvement. One issue which is however quite important is that of cost. This has infact become a billion dollar market and is indeed a very heavy financial burden on the common man. Cost cutting methods can be devised by the companies and should really not be seen as a big problem by the companies as the demand for these devices is so high. Although more serious scientific research and trials are needed, if it is made cost effective, it can still be useful for various inflammatory disorders. Like anything else, as the market widens, automatically, it becomes cost effective in the long run. References: 1. Hinman MR, Ford J, Heyl H. Effects of static magnets on chronic knee pain and physical function: A double blind study. Alter Ther Heal Med, 2002; Vol.8, 50-55. 2. Aaron RK, Ciombor DM. Therapeutic effects of electromagnetic fields in the stimulation of connective tissue repair. JCell Biochem. 1993; Vol.52, 42-46. 3. Yan QC, Tomita N, Ikada Y. Effects of static magnetic field on bone formation of rat femurs. Med Engin Physics. 1998; Vol.20, 397-402. 4. Weintraub MI, Cole SP. Pulsed magnetic field therapy in refractory neuropathic pain secondary to peripheral neuropathy: electrodiagnostic parameters--pilot study. Neurorehab Neural Repair. 2004; Vol.1, 42-6. 5. Sandyk R. Successful treatment of multiple sclerosis with magnetic fields. Int JNeurosci. 1992; Vol.66, 237-250. Competing interests: None declared |
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Timothy N Harlow, Palliative Care Physician Hospiscare, Dryden Road, Exeter EX5 4LA
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I am pleased to see further attention focussed on magnet therapy. Finegold and Flamm rightly point out the difficulty of controlled experiments in this area, but speculatively invoking subconscious detection of “a tiny drag when the bracelets were near ferromagnetic surfaces” is not science. Neither is the entertaining anecdote about the refrigerator magnets in dress shoes science either. Any researcher citing that sort of evidence in favour of a specific effect of magnets would, deservedly, be ridiculed. The plea for evidence based medicine is laudable but I am unclear why the authors chose to ignore the evidence that those who wear strong magnetic bracelets report significantly less pain than those who do not wear them –whatever the mechanism (1). These are not “extraordinary claims” just careful observation. As for underlying mechanisms; we always know less than we think we do. However, even placebo benefits are relevant here, as pain is such a subjectively mediated outcome. Indeed, we acknowledged the placebo problem in our study {1} which, much as Finegold and Flamm suggested, used weak bracelets as well as dummy bracelets that did not contain magnets as a part of the study design. Despite our efforts the study was upset by a manufacturing problem which left us under-powered to detect any specific effects. Even with only half our intended sample, we came very close to detecting a significant difference (p=0.07). However, there is still a potential criticism that the weak magnets were in some way inferior as a placebo in terms of believability, and so there is still more work to be done refining the use of such placebos and that is continuing. The “financial harm” (£30-40) from the bracelets which usually last for years (and we suggest only using those with a money back guarantee) compares well with even the cheapest medications such as Ibuprofen 600mg tds for 12 months of £48.24p. (2) Such medication has well established dangers which seems not to be the case with magnets. Given the low amount of harm, and the clear evidence of benefit (albeit potentially caused by placebo effects), the clinical equipoise seems to be in favour of advising patients that magnetic bracelets may be worth a try, as some people find the devices useful. Regarding the argument proposed about MRI scanners, the large magnetic fields are only operative for a short time and it is not surprising there is no effect noted. I deplore the ridiculous and unsupported claims (such as increasing longevity and curing cancer) made for magnets as well as for lots of other treatments. These should be vigorously attacked. However, simply assuming that magnets have no effect, as the authors of this editorial do is similarly unfounded! Finegold and Flamm are incorrect to state that “patients should be advised that magnet therapy has no proven benefits”- there are proven benefits on pain from osteoarthritis of hip and knee (1) - although only from magnets of around 180mT, not necessarily the cheapest. Finegold and Flamm, in this leader, have failed to concentrate on established fact and so unfortunately have not advanced our understanding of this area. The correct conclusion to draw from the evidence base to date is that some patients clearly benefit from the use of magnet therapies for pain. The size of effects found in studies is clinically meaningful, and seems to be more apparent in studies where strong magnets are used (see review of the literature in the Discussion of our paper [1] for more detail). However, the jury is still out as to whether these benefits are due to a placebo effect, a specific effect of the magnets or a combination of both these things. Further research is needed to resolve this issue, but in the meantime there seems little harm in patients buying bracelets, as long as they have a money-back guarantee. References: 1 Harlow T, Greaves C, White A, Brown L, Hart A, Ernst E. Randomised controlled trial of magnetic bracelets for relieving pain in osteoarthritis of the hip and knee. BMJ 2004;329: 1450-4. 2 British National Formulary, September 2005. Competing interests: I am a published researcher in this area. |
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Ray Padfield-Krala, see above Steers Farm Pigstye Green CM5 0QF
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I am amazed that this article has been published. It seems to me that all that Finegold and Flamm are doing is finding fault with a therapy they can't accept based on the over hyped American market place and on the weakest arguments put forward by those who don't know what they are talking about which are the vast majority of companies and individuals promoting Magnetic Therapy! A case in point regarding the comment abvout sports people promoting the therapy is that you hardly see these people wearing the product other than in the advert! Thats not proof that it works! and if people believe that then yes they are gullible. With regard to the flawed trial which was published in the BMJ last year I made my comments known then and repeat them now. The published trial report kept refering to the product used in the trail as a "bracelet", it wasn't a bracelet! It was a magnetic wriststrap with a much larger and stronger magnet than used in a standard magnetic bracelet. A bracelet to most people is a jewellery type item which is offered for sale with magnets that are far weaker than the one used in the trial. This misleading statement lead many people to look to these items to help them with pain relief which are totally inadequate and vary greatly in magnetic power depending on the product and company. The report also mentioned price! why? A magnetic "bracelet" sold at a boot fair for say £15 was then offered for £30 as it now fit the criteria set out in the report. Its significant that these items are now for sale at your local Poundstore. So what are Finegold and Flamm basing their report on? Misleading claims that do not stand up even to a a non medical layman? or evidence that they themselves have compiled? For example it is claimed that "self treatment may lead to the underlying condition being left untreated". Not so, drugs do that, the principle of using magnets is promote the bodies nutural healing mechansm not to block the pain censors! Using the lack of vascular dilation is another argument. Why should the skin go red where a magnet is placed if the area doesn't need an improved blood flow? A massage will do that so will heat. Picking out the weakest or misleading point in an article or advert is not evidence that it doesn't work. Citing the lack of effect using an MRI machine is not proof! The lack of exposure could be a factor also the lack of direct application to the pain site may influence the result, thus creating a flawed trial. A final point is I note the lack of comments from those who distribute the product used in the 2004 published trial. They were quick to claim that "it was our magnetic product" that worked due to it's supposedly superior properties implying that other products were not as good when in fact the magnet actually used in the trial IS NOT the same magnet used in the current model offered for sale! Unlike drugs there are little or no long lasting side effects, a good quality magnetic device will last a lifetime and most come with a replacement warranty or guarantee and at a fraction of the cost of most other conventional treatments. If it does no harm and is sold ethically and with the right advice and information and at an affordable price then what possible harm can it do? R. Padfield-Krala MAGNETiC CoBCMA Competing interests: Magnetic Therapy product manufacturer |
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Roger Coghill, Research director Pontypool, NP4 5UH
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Finegold and Flamm, like many before them, question the claimed efficacy of static magnets. Space considerations might have precluded their reference to the 20 or so positive studies, and this detracts from the force of their argument, but one inexcusable lacuna was their failure to discuss animal experimental results, where the conceded strong placebo effect of magnets is not a possible confounding factor. For example scintigraphic studies of magnets applied in equine laminitis revealed a significant therapeutic effect (Kobluk and Johnston, 1994). Such magnets are used throughout the equestrian world to apparently great effect. There is moreover a large body of largely untranslated literature supporting magnet therapy from eastern bloc countries and from China, where magnet therapy is routinely practised in hospitals. Whilst the Finegold and Flamm editorial does well to keep this issue before the medical community, it cannot do justice to the finer detail, which requires a far more thorough review in order to achieve a balanced conclusion. Absence of an accepted interaction mechanism does not mean absence of any interaction. Competing interests: My laboratory researches the biological effects of non-ionising electric and magnetic fields and radiation, and an associated company distributes magnets for therapeutic purposes. |
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Agatha P Colbert, Investigator National College of Naturopathic Medicine 049 SW Porter St., Portland, OR 97201
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Having been cited twice, I would like to contribute my own thoughts to the dialog about magnet therapy. Regrettably, Drs. Finegold and Flamm appear to have missed the point of our 1999 magnetic mattress pad study [1]. Both the control and experimental groups in that clinical trial expressed comfort with the firmness of their respective mattress pads during the first 8 weeks. And, indeed the VAS data from both groups indicated improvement (decreased pain scores) over those first 8 weeks. However, this possible early “placebo effect” (a belief on the part of the control group that the comfort they were experiencing was proof that they were sleeping on the “real” mattress pad) wore off by Week 8. The control group experienced no additional pain relief after that point. Participants in the experimental group, on the other hand, continued to decrease their VAS pain scores significantly throughout the entire 16 weeks of the study, thus demonstrating a true treatment effect. The placebo issue in trials of static magnetic field (SMF) therapy is a challenging one. Placebo controls, the so-called “sugar pills” which can be manufactured to look like active agents, were developed as the gold standard for pharmaceutical trials. When the effectiveness of physical interventions, such as permanent magnets, surgery, acupuncture, ultrasound or physical therapy is tested, however, there is no available gold standard to be used as a comparison intervention. To further confound the situation, clinical experience suggests that, magnetic devices should be applied intermittently for extended periods of time in order to achieve maximum benefit, thereby necessitating home use of the devices, in unsupervised settings. Potential sham devices have been evaluated in previous SMF studies. Wolsko [2] demonstrated that shielding the exterior surface of the magnet served as an effective blind as long as the participant was wearing the magnetic device. When the device was removed from the body, however, the interior (active magnet) surface, could easily be tested. Other groups of investigators [3] employed a very low strength magnet as the sham and observed significant improvement in both the control and experimental groups. These investigators correctly pointed out that, because we do not yet know what an appropriate therapeutic magnetic field dose is, we cannot be certain that low strength magnets are truly inert interventions. Other researchers have used the “honor system” and asked their subjects not to test the magnets. This latter approach seems to us an invitation, to those who had not previously thought of testing their device, to do so. It must be acknowledged that short of anesthetizing subjects or continuously observing them over the course of a trial, participant blinding can never be guaranteed in SMF studies. In addition to other standards for judging the methodology used in SMF research, a quality assessment must include a report on the success with which all other members of the research team (the investigators, the outcome assessors and the data analysts)were blinded. One final comment, I would suggest that, instead of the Google search recommended by Finegold and Flamm, readers who wish to deepen their scientific knowledge of magnet therapy might consult the recent comprehensive and authoritative text of Rosch and Markov, Bioelectromagnetic Medicine [4]. 1. Colbert, A., et al., Magnetic mattress pad use in patients with fibromyalgia: a randomized double-blind pilot study. Journal of Back and Musculoskeletal Rehabilitation, 1999. 13: p. 19-31. 2. Wolsko, P.M., et al., Double-blind placebo-controlled trial of static magnets for the treatment of osteoarthritis of the knee: results of a pilot study. Altern Ther Health Med, 2004. 10(2): p. 36-43. 3. Segal, N.A., 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(10): p. 1453-60. 4. Rosch, P.J. and M.S. Markov, Bioelectromagnetic Medicine. 2004, Marcel Dekker: New York. Competing interests: None declared |
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Marko Markov, President, Research International 135 Arielle Ct. Suite E, Williamsville NY 14221, USA
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I was surprised to read the Editorial published on line at the WEB site of the British Medical Journal. I was even more surprised that this one-page text was not printed as a letter to the editor, but as an Editorial. In other words, this is the position of the Journal. It is really unfortunate that the BMJ took this approach. The authors, L. Finegold and B. Flamm, published their view under the title “MAGNET THERAPY Extraordinary claims, but no proven benefits”. One may wonder why Leonard Finegold, Professor of Physics did not use his knowledge to inform the audience that it is not the magnet, but the magnetic field generated by the permanent magnet that is responsible for any beneficial effect. Who, if not a professor of physics should know the difference between a refrigerator magnet and an MRI system that operates with complex magnetic fields. It is unclear what was the actual goal of this publication? If the authors’ intent was to demonstrate their knowledge of the literature on the use of magnetic fields for therapeutic purposes, they obviously failed. They cite as a primary source of information the New York Times (Their ref.#1) but are unaware of the book BIOELECTROMAGNETIC MEDICINE published in May 2004 by Marcel Dekker. In this book 50 chapters, written by 86 experts from all over the world, are dedicated to various aspects of therapies that utilize magnetic fields, including the use of permanent magnets. The authors chose a paper on which I am a co-author (ref.#5) and told the readership that “Patients with fibromyalgia detected which sleeping pads were magnetic by their mechanical properties, by “comfort with the firmness”5 and thus unblinded the study6 “. Wrong, gentlemen, wrong. The patients in our study were unable to evaluate “which one…” because they had only one mattress pad, delivered to their house by the manufacturer. Even the principle investigator was blinded about the “real” vs. the “placebo” mattress until the end of statistical analyses. One may wonder how it is possible to detect the presence or absence of a magnetic field by the mechanical properties of the sleeping pad? For your information, gentlemen, both the “placebo” and the “real” mattress pads were absolutely identical in appearance. The only difference was that the “real” mattress pad had domino size magnets, while the “placebo mattress had exactly the same domino pieces which were not magnetized. I could stop here with the demonstration of misleading statements of the authors of the Editorial, but I need to point out two more facts: false assertions: the authors use the statement from our magnetic mattress pad study #5, to say that it unblinded study #6 (Sorry, but the authors of study #6 did not make reference to study #5. I would like to make it clear to the audience, that study #5 had highly positive results, not negative as the authors of the editorial intended to show. More than 30% improvement was observed in 7 of 8 clinical outcomes in the patients who participated in this double blind study. It is shame that a study was misrepresented in such a way in the British Medical Journal, a leading medical journal. I tried to search for the references in the Editorial and found that one reference was the New York Times (ref#1), one was from an Internet site and the author L. Johnson stated at the bottom of the article (ref.#3) that it was “Adapted from an article appearing in Paraplegia News, March and April, 2000”. It is inappropriate to use references like these as scientific arguments. If you include ref#13, which deals with magnetic fields of MRI, the supporting evidence for this editorial becomes weak, very weak, especially when the reported findings in some of the cited studies are misinterpreted. I have read and reread this Editorial, trying to find the reason for it having been written. I failed to find one other than “making extraordinary claims”. The bioelectromagnetics community, the medical community, and the general public have been done a serious disservice. Nearly every paper on magnetic field therapy starts with a statement “this is a controversial area”. This is probably correct. What is needed to make this area of therapy less controversial and acceptable to mainstream medicine? v Science needs to clarify for the general public, the manufacturers, the vendors, and the users (health professional and patients) what is correct evidence-based and what is just “extraordinary claims” v This requires proper terminology (an element that is notably missing in a paper written by a Physics professor), and the clear identification of criteria suggested for establishing the validity of vendors’ claims. v Scientists need to explain to consumers that “not all magnets are equal”, just contrary to what was done by one of the authors of the Editorial. v The concept that the magnetic field, not the magnet, has the therapeutic potential must be made plain. And it must be emphasized that the surface strength of the magnet is not as important as the magnetic field that actually reaches the target tissue and causes the biological response. In conclusion: The British Medical Journal should withdraw this Editorial because it is misleading, false and does not contribute to the development of scientific knowledge. The Editor should seek out scientists who are capable of presenting the problem with a critical attitude – identifying what is inaccurate, even misleading and what is correct and beneficial. Do not forget that magnetic field therapy has centuries of history and that over the last 60 years more than 3 million people worldwide have benefited from it. It is the duty of scientists and clinicians to search for the proper choice of magnetic field and the most appropriate protocol of application. Double blind studies, placebo vs. real, search for mechanisms of action – all this is needed and must be done in a proper scientific way. This Editorial, however, did not contribute to the future of magnetotherapy. References to be considered: Colbert AP, Markov MS, Banerji M, Pilla AA – Magnetic mattress pad use in patients with fibromyalgia: a randomized double blind pilot study J Back Musculoskeletal Rehab 1999:13;19-31 – cited as # 5 in the Editorial Rosch PJ, Markov MS (eds) BIOELECTROMAGNETIC MEDICINE, Marcel Dekker 2004, 850 pp. ISBN # 0-8247-4700-3 Competing interests: None declared |
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Carlton F. Hazlewood, Retired, but active in study of biological effects of magnet fields P.O. Box 130282 77381-6335
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I wish only to refer the authors Finegold and Flamm to the following publications for consideration of the evidence for the therapeutic value of magnetic fields (including fields produced by magnets): 1. Archives of Physical Medicine and Rehabilitation. 78: 1200-1203, 1997. 2. “Magnetotherapy: Potential Therapeutic Benefits and Adverse Effects”. Ed. by Michael J. McLean, Stefan Engstrõm and Robert R. Holcomb Floating Gallery Press. 2003. 3. "Bioelectromagnic Medicine". Ed. by Paul J. Rosch and Marko Markov. Marcel Decker. 2004 Competing interests: None declared |
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Nyjon K Eccles, Medical Director, Chiron Clinic, Harley St The Harley Street Practice, 104 Harley St, London W1G 7JD
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I am very disappointed that the BMJ saw fit to publish this editorial. The only comment made by the authors that I agree with is the non-evidence-based “cure-all” claims that are sometimes made on the internet in relation to static magnetic fields. However, this editorial does a great disservice to the vast amount of published and peer-reviewed evidence, that seems to have been overlooked by the authors, that would support a genuine and real effect of static magnetic fields on tissues, animals and humans (Rosch & Markov, 2004). A critical review of all the controlled and blinded trials published in 2005 demonstrated that 73.3% of the better quality studies demonstrated a positive effect of static magnets in achieving analgesia across a broad range of different types of pain (neuropathic, inflammatory, musculoskeletal, fibromyalgic, rheumatic and post-surgical) (Eccles, 2005). Furthermore, there seems to be a real effect of static magnetic fields to expedite wound healing. Significant leg ulcer healing is achieved over a relatively short period. After 12 weeks ulcer areas were reduced on average by 91.2% whereas in the placebo group there was an average increase in area of 3.8% (p < 0.04) (Eccles & Hollinworth, 2005). Furthermore, the same magnetic device prevented recurrence of leg ulcers in 100% of chronic recurrent leg ulcer sufferers with a potential cost saving to the NHS of £150 million annually. (Eccles, 2006, In Press). This device has now been accepted onto the UK drug tariff (March 2006). The discussion of blinding has always been topical but again the authors have not considered that 4 of 21 published double blinded studies that actually used an attenuated power magnet as placebo, thereby circumventing the problem of patients self testing their device. Incidentally, on critical review, these studies scored 3, 4, 5 and 5 on the 5 point Jadad quality control scale (Eccles, 2005) and all reported significant analgesic effects compared with placebo. The comments in relation to the different mechanical properties of test and placebo do not apply to all studies but to only 2 of the RCTs that used both the placebo and test in the same subject. The statement that “even theoretically- magnet therapy seems unrealistic” is again not consistent with existing scientific evidence. Why is this concept such a challenge to contemporary thinking? Subtle magnetic fields can produce a physiological effect. Pico-tesla range electromagnetic fields have been shown to have significant effects on nerve regeneration (Turing, 1952). Electrical activity exists in the body at all times e.g. the beating heart, nerve conduction. Mechanical loading of bones generates electrical currents. The discovery of magnetic material (deposits of magnetite) in the human brain might suggest that we are physiologically designed to respond to magnetic fields (Kirschvink et al, 1992). We now know that wound and hard tissue repair process involves electric currents. Becker & Selden (1985) proposed the existence of an electromagnetic system in the body that controlled tissue healing. When the electrical balance of tissue is disturbed by an injury, an injury current is generated, with the resultant shift in the local tissue current triggering a set of biological repair systems. As healing progresses the injury current diminishes to zero. It has been noted from Space flight that deprivation of the electromagnetic wave between the earth’s surface and the ionosphere leads to abnormal body functioning (Owen, 1986). The essence of cell to cell communication lies at least in part in transfer of subtle ionic currents across the cell membranes. Are these not all potential sites of action for an appropriately applied magnetic field? Has basic high school physics not taught us that ionic movement can be influenced by a magnetic field? I found the comments in relation to MRI scanning just plainly ridiculous. Presumably, if there was no ability of the magnetic field to affect tissues we could not use it as a scanning modality as this is the main fundamental principle of the technique i.e. measuring the differential effect of how the field affects different tissues, normal and abnormal. Dosage and duration of exposure are important considerations here. Finally, I trust that the BMJ will take an unbiased approach in publishing at least some of these response letters. I somehow doubt that these will reach the National Press with the same gusto that the Finegold and Flamm editorial did. Far from misleading the public, the existing scientific data would suggest that there are several specific therapeutic advantages to using appropriately-applied static magnetic fields; not least in the arenas of pain and wound healing. References Becker RO, Selden G (1985). The Body Electric. Electromagnetism and the Foundation of Life. New York, Morrow. Eccles NK, Hollinworth H. A pilot study to determine whether a static magnetic device can promote chronic leg ulcer healing. Journal of Wound Care 2005, 14(2): 64-67 Eccles NK. A critical review of randomized controlled trials of static magnets for pain relief. Journal Alternative Complimentary Medicine 2005,11, 495-509 Kirschvink JL, Kobayashi-Kirscvink A, Woodfors BJ Magnetite biomineralization in the human brain. Proc US Natl Acad Sci, 1992, 89:7683 -7. Owen D Introduction to magnet therapy. J Alt Med, 1986, May; 6-7. Rosch PJ, Markov MS (eds) Bioelectromagnetic Medicine, Maercel Dekker 2004, 850 pp ISBN # 0-8247-4700-3 Turing AM. The chemical basis of morphogenesis. Philos Trans R Soc London B Biol Sci, 1952, 237:37-72. Competing interests: None declared |
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Leonard Finegold, Professor Department of Physics, Drexel University, Philadelphia PA 19104, USA, Bruce L. Flamm
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General Comments We thank the many sincere journalists and writers, and the Rapid Responders for their reporting and comments. The editorial attracted Media Coverage and comment in several languages. Some Rapid Responders were highly critical of our conclusions. Perhaps this is not surprising since it has come to our attention that several of the Rapid Responders are heavily involved in companies that sell magnets for therapy, and yet, inexplicably, stated, “Competing interests: None declared”. For example, responders MM-13 and CFH-14 state, “Competing interests: None declared” yet their website Theramagusa http://www.theramagusa.com/staff.htm [1] documents obvious competing interests. Also, responder NKE_15 states “Competing interests: None declared”, and neglected to mention his “natural” clinic using magnets http://www.chironclinic.com/cc-pain.htm [2]. To avoid an overlengthy response, we first summarize our position, and then answer each Response. We rest our case against magnet therapy upon the following: —The physics of magnetism is extremely well understood and there is no plausible mechanism by which ordinary magnets could cause healing. —A non-moving or static magnet produces only a magnetic field. It produces no electric field and no electromagnetic radiation. —There is no convincing evidence that a magnetic field of any strength has any significant effect on human tissue. healing or otherwise. [3] —There is convincing evidence that even extraordinarily powerful magnetic fields, such as those produced by superconducting magnets in MRI machines, cause negligible effects on human tissue. [3] —Moving magnets or pulsed electro-magnets can create electric fields which could have some effect on living tissue. Whether such effects could be beneficial or harmful remains investigational. In any case, we restricted our paper to non-moving magnets and time-invariant magnetic fields. —If the low-level magnetic fields of refrigerator or “healing” magnets did cause significant affects on human tissue then the quite powerful magnetic fields produced by MRI machines could be quite dangerous. Yet more than 100 million MRI scans have been done with no harm whatsoever (apart from occasional claustrophobia). — Rare reports of injury related to MRI scans always involve metal foreign bodies or other metal objects inadvertently brought into the MRI area. —MRI machines produce three types of magnetic fields, two of which are not static. Never-the-less, there are no reports of ill effects caused by even extremely high magnetic fields on human tissue, despite such ill effects having been sought when MRI scanners were first proposed. —It could be argued that magnets might heal via some mysterious as- yet undiscovered mechanism. However, experiments thus far have not shown convincingly that any healing effect exists. —There may be a placebo effect associated with the use of magnets. Since human tissue is not significantly affected by magnetic fields, magnets should cause no physical harm. Hence, if patients insist on using magnets for “healing”, they should probably be advised to use the cheapest ones available. Although it is highly improbable, let us assume that a significant effect of static magnets on human tissue could be demonstrated. What is the likelihood that this effect would promote healing?—very low to practically nil. Some of the reasons why this is so are explained in another article [4]. Magnet healing claims have been challenged by scientists and physicians for more than 200 years. We are certainly not the first in modern times to dispute the claims made by magnet merchants and magnet healers. For example, in 1999 the Regence Group (a medical consortium caring for three million patients) reviewed the medical literature and developed a policy indicating that magnet therapy had no proven value for the treatment of any type of pain. They reached the following conclusion about magnet therapy: “The data from the above randomized, placebo- controlled clinical trials fails to demonstrate that biomagnetic therapy results in improved health outcomes for any type of pain. An updated search of the MEDLINE database through February 11, 2005 did not identify any additional studies which alter this conclusion” [5]. CRITERIA FOR EVALUATION OF MAGNET HEALING CLAIMS In the spirit of “Come now, and let us reason together”, or of a consensus panel, we invite our responders and others to meet (preferably at a conference) to establish criteria for the evaluation of trials of magnet therapy (contact LF). Famous physicist Richard Feynman noted that “The first principle is that you must not fool yourself—and you are the easiest person to fool.” [6] It would be wonderful if magnets (or crystals, or amulets) could eliminate pain and heal all sorts of ailments. Sadly, it appears that they can not. For those who believe otherwise we propose the following criteria. The F criteria (Feynman, Fields) below should obviate much self- deception. We ask no more of magnet therapy studies than would be asked of any other studies. Our responders are invited to apply the following criteria to the research which they believe supports magnet therapy. (Some of these criteria were mentioned by one of us earlier in reference 10 of the editorial) : —The trial should be publically registered in advance [7]. —Clearly explained randomising, by someone outside the experimental team —For studies in which magnets are used to decrease pain, there should be defined pain by, for example, capsaicin [8] or heat or cold on healthy subjects—for natural diseases are variable. —Any skin contact should be through a biologically inert material. —A cross-over experimental procedure. —Subjects to report if they think the magnet is present of not (there may be human sensitivity to fields...discussed later). —A “dose”-response curve would be compelling. We all live in a (small, Earth’s) magnetic field, as “zero” field. —The papers should be published in a journal which (like the BMJ and others) has a house statistician [9]. —Replication of results. Since claims of healing via magnets are extraordinarily claims, it would be reasonable to withhold recommendations for magnet therapy until a study showing “healing results” can be replicated. We compliment BMJ on the visionary idea of Rapid Responses. Hopefully, other medical journals will follow this wonderful example. However, we believe that the editors of BMJ are a little too lenient with their rapid responses. Perhaps it is possible to be too kind. In the interest of fairness and allowing all points of view they may inadvertently allow statements of marginal credibility to slip into a scientific evidence-based medical journal, thus giving an international forum touting unproven healing practices. Perhaps an editor could screen rapid responses for statements that do not comport with scientific principles and evidence-based medicine. Such a screen would have excluded many of the rapid responses to our paper. Rapid Responses might be screened with a brief Google search. If linked to sites that make paranormal claims or other outrageous, bizarre unscientific claims then their comments may not be appropriate for a scientific medical journal, even in electronic format. Of course, this type of screen would rarely exclude rapid responses, since the vast majority of papers published in BMJ do not deal with bizarre topics and the vast majority of rapid responses comport with scientific principles and evidence-based medicine. DETAILED REPLIES TO RAPID RESPONDENTS We identify them by initials and their sequence of response. GJR-SW-1 We applaud their research—especially the topic—and would happily participate in extending it to our favourites, such as chocolate, coffee, desserts and (if we can think of a way of doing it) sampling the deserts. The use of cow magnets (NOT refrigerator magnets for refrigerator notes, but for collecting iron wire eaten by cows) has long been advocated for improvement of car fuel consumption...alas, it doesn’t work. We’d be interested in the “domestic gas bill”, as it’s new to us, and also any more research on wine. JTHT-2 Thank you. We deliberately restricted our work to time-invariant and motion-invariant or static magnetic fields, for these are the ones most used in commercial “magnet therapy”. BMJ editorials are, perforce, written in a cruel confining compass. So it is understandable that some responders missed that the editorial was restricted to static (permanent-type) magnets, which are the “healing magnets” of most commercial sales. In a longer review, which we are now writing, we aim to briefly mention TMS as a promising modality (editorial reference 10 did mention it), and thank JTHT for providing us with recent references. We did mention it in interviews to reporters. Incidentally, there are papers claiming the influence of low frequency, low intensity magnetic fields on humans, for healing and production of cancers (electric power line fields, cell phones). Again, these do not involve static magnets and the evidence in favour of any effect is very sparse. JD-3 Thank you for “short and insightful examination of the field”...that was our aim. We would be grateful for a list of references to your work. The decay of field with distance, as you summarize well, is popularly illustrated by showing that a magnet won’t hold a paper clip from falling, if separated by a few thicknesses of paper. This is yet another reason why magnet therapy seems highly implausible, even if human tissue were significantly affected by magnetic fields, which it is not. The magnetised water idea is reminiscent of how homeopathy works, ie that the water has a memory. Magnetisation of water is supposed to reduce calcium salt deposition in boilers; we’ve seen commercial adverts for this, but no tests. The concept of magnetised water, as here, is at variance with known physics. JMD-4 We thank JMD for an charming early reference to the efficacy of magnets. Readers interested in history may be interested to know that magnets have been sold as supposedly healing devices for hundreds of years. An early proponent of magnet therapy, Franz Anton Mesmer (1734- 1815), became so successful in Paris that in 1784 King Louis XVI established a Royal Commission to evaluate his claims. The commission, that included Antoine Lavoisier and Benjamin Franklin, conducted a series of experiments (which are still good by modern standards) and concluded that all the observed effects could be attributed to the placebo effect along with the power of suggestion. Thus, a magnet therapy was scientifically debunked more than 200 years ago. [10] [Reference 13 of editorial] [11]. We thank the author for a clear explanation of the difference between time-varying magnetic fields, and the static (in time) fields of our editorial. JNW-KB-6 We would like to see references for the experimental phenomena mentioned, and could then comment. MIW-7 The author ascribes an agenda to the editorial, also some interviewers have probed a possible bias. If anything, most physicists would be delighted scientifically (and personally, since physicists are subject to all the ills that flesh is heir to) to find that magnetism has healing properties, and so would indeed have an agenda—an agenda to find that magnet therapy does work. Alas, it does not. The unipolar etc. nomenclature is confusing. Perhaps it can be simplified by stating that the discovery of monopoles would result in a Nobel prize, for north and south poles always come as pairs ie dipoles or “bipoles”. This does not stop purveyors of magnets from selling ostensibly “monopolar” magnets. One wonders why they have not been contacted by the Nobel Committee. “Penetration of field”, identified by a single field strength and single depth, is inadequate. We shall be interested to read the author’s reference 11, assuming it fulfills the criteria listed above. We agree with his terminology of “presumed” for effects, since the effects are presumptive indeed. We presume that the author controlled for the confining effects of an MRI examination by also using an “open” MRI scanner. MIW-7 states that, “the authors are clearly unaware of Transcranial Magnetic Stimulation (TMS) that creates a time-varying magnetic field”. TMS was indeed mentioned in Reference 10 of the editorial. Furthermore, MIW-7 either did not carefully read the editorial and/or overlooked the fact that it clearly states that it is confined to static magnets, of the type typically sold for healing. These magnets, like common refrigerator magnets, produce time-invariant magnetic fields—not time-varying magnetic fields. We concur entirely that “authors ...need to be knowledgeable about the current literature” and thank for him providing such an immediate self example in his Rabid Response (see preceding paragraph). That authors “refrain from making unsubstantiated and erroneous conclusions” is a consummation devoutly to be wished, and details of how to avoid erroneous conclusions would be awaited with baited breath—and appreciated—by the scientific community at large. We regret that the author is unfamiliar with the modern mode of scholarly dispassionate discourse (and reluctantly repressed the temptation to reply to the author in his mode). AJ-PK-8 We have addressed most of the comments above. That an idea (of magnets and healing) was held in antiquity is certainly of interest to the historian of science. It is not, alas, a good predictor of its veracity in modern times. Amulets, skull drills, and special arrangements of bones were also popular healing practices in ancient times but—we trust—are not often used by contemporary physicians. TNH-9 This study (reference 4 of the editorial) was more carefully performed than most. It is not clear why “speculat(ion)...is not science”. A similar concern, to that of the editorial, is mentioned by at least one group of investigators using magnets on horses [12]. It is not clear that p = 0.07 is an adequate probability [12]. The argument that magnets fulfill “Primum non nocere” is acceptable, except for harm to the pocketbook and possible delay of appropriate medical care. “MRI scanners...it is not surprising that there is no effect noted”. We suggest that the author contact MIW-7, who reports such effects. The author suggests that placebos are beneficial. We do not address here the medical ethics of knowingly prescribing a placebo to a patient, who is deliberately led to believe that it is an active treatment. However, if patients insist on using magnets, after being informed of their lack of efficacy, they probably should be advised to use the cheapest ones available. Finally, we are sorry that the anecdote, about magnets in dress shoes, distressed the author. RPK-10 We thank the author for alerting us to the very many Rapid Responses (we think the reader will enjoy them) to the publication of TNH-9 above (reference 4 of the editorial), and thank the author for an impassioned response. We do not recognise “boot fair” nor “Poundstore”, and suppose these to be Anglicisms. RPK, speaking for his company that sells supposedly-healing magnets, makes many unsubstantiated claims. However, RPK emphatically states that, “...the vast majority of companies and individuals promoting Magnetic Therapy don't know what they are talking about...” We fully agree with the author on this point. Most of RPK’s other comments have been addressed above. RG-11 We agree entirely with the author that, just because the theory of an effect is not apparent, the effect could possibly still be there. However, when the vast preponderance of theory is against any effect, then healing claims demand careful scrutiny—“Extraordinary claims require extraordinary evidence”. We are curious how controls are used in equine healing—see also the proposed criteria above. A more recent equine study found no effect of magnetic fields [12]. We would be interested in details of magnet therapy in China and Eastern Block countries...are there reviews? APC-12 We are in agreement with the author about the difficulty of controls to a magnet. The author is quite aware of the difficulties of subject compliance. We are sympathetic to the difficulties of hiding the existence of the magnets from the subjects and the experimenters [Reference 10 of the editorial] [13]). The inadvertent detection by experimenters has been addressed by others too (eg [12]). We understand that one would like to explore the possible experimentally-accessible combinations of field magnitude and of duration in which pain relief could be detected, if present. MM-13 We were unable to find archival references to the prevalence of commercial magnets for healing, and hence had to resort to the ones quoted. We would be grateful for archival references. Time-varying magnetic fields are of great interest, and were indeed briefly addressed in Reference 10. However, we confined our discussion to static magnets, the type commonly sold for magnet healing. “Magnetic field therapy has centuries of history”...please see the reply to AJ-PK-8 above...“more than 3 million people worldwide have benefited from it”...we gently challenge this statement. On second thought, we vigorously challenge this statement. It would probably be more accurate to state that millions of people worldwide have purchased “healing” magnets in the hope that they would be cured of various aliments. This has, no doubt, greatly enriched the purveyors of magnets but there is no valid evidence that anyone has been cured of anything by magnets. “Field”: Perhaps this is a philosophical point. The modern concept of “field” originated with Michael Faraday, and is indeed most useful. However, there are other ways of casting interactions. We note that MM-13's Rabid Response is actually longer than the original editorial. We invite the author to apply the criteria above. The author of this response seems quite sure that we have, tragically, overlooked the incredible healing power of magnets. In fact, the book cited and co-edited by the author, makes the following impressive claim. “In the decade to come, it is safe to predict, bioelectromagnetics will assume a therapeutic importance equal to, or greater than, that of pharmacology and surgery today. With proper interdisciplinary effort, significant inroads can be made in controlling the ravages of cancer, some forms of heart disease, arthritis, hormonal disorders, and neurological scourges such as Alzheimer's disease, spinal cord injury, and multiple sclerosis. This prediction is not pie-in-the-sky. Pilot studies and biological mechanisms already described in primordial terms, form a rational basis for such a statement. - Bassett, 1992” [14]. Thus, according to the author’s book, bioelectromagnetics should have overtaken medicine and surgery by the year 2002. We are puzzled as to what happened, since we are not aware of this astounding transformation. MM-13, like CFH-14, seems to be too modest to refer readers to a
website, Theramagusa, where he is featured
CFH-14
Most of the comments have been addressed above. We mildly defend
ourselves against the implication that all our references are acquired via
Google. This engine was mentioned in the context of commercial magnet
therapy, and was certainly not intended as a sole source for published
papers. Although Google and similar engines have had a great impact [15]
and may have engendered a gender change [16], most readers will use
several computer engines. The National Library of Medicine “PubMed” lists,
on the whole, competent peer-reviewed work and we are, of course, quite
familiar with its use.
CFH-14, like MM-13, seems to be too modest to refer readers to a
website, Theramagusa, where he is featured
NKE-15
We thank the author for a measured response. Most of the comments
have been addressed above. We are disappointed that NKE found some of our
comments to be “just plainly ridiculous.” In the interest of fairness, we
urge readers to visit this responder's natural healing site to learn about
revolutionary new techniques including Rheumatic Rub, Ancient Cupping,
Oxygen Assisted Photon Detoxification, Biological Terrain Analysis, and
Magnet Bioresonance Therapy [2]. BMJ readers are encouraged to draw their
own conclusions about what is “just plainly ridiculous.”
CODA
Preliminary experiments, have been done (with good double-blind
controls and other experimental designs) on whether humans can detect the
presence of a magnet of the kind used in magnet therapy [13], and they can
not (at the significance level of the experiments). We were unable to
reply to some emails, which had an incomplete address and no affiliation
or other address. We shall be happy to reply when we receive the missing
information.
REFERENCES
[1] Theramagusa. http://www.theramagusa.com/staff.htm [accessed
January 27, 2006].
[2] Chiron http://www.chironclinic.com/cc-pain.htm [accessed January
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Competing interests:
None declared |
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