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'''Magnet therapy''', '''magnetic therapy''', '''magnetotherapy''' or '''magnotherapy''' is a [[complementary and alternative medicine]] practice involving the use of static [[magnetic fields]]. Practitioners claim that subjecting certain parts of the body to magnetostatic fields produced by permanent, typically [[NdFeB]] magnets has beneficial health effects. Magnetotherapy is considered pseudoscientific by its critics.
'''Magnet therapy''', '''magnetic therapy''', '''magnetotherapy''' or '''magnotherapy''' is a [[complementary and alternative medicine]] practice involving the use of static [[magnetic fields]]. Practitioners claim that subjecting certain parts of the body to magnetostatic fields produced by permanent [[magnet]]s has beneficial health effects. Magnet therapy is considered pseudoscientific due to both physical and biological implausibility, as well as a lack of any established effect on health or healing.<ref name=Park_Voodoo /><ref name='Wanjek_BM'>{{cite book | last = Wanjek | first = Christopher | authorlink = Christopher Wanjek | coauthors = | title = Bad Medicine: misconceptions and misuses revealed from distance healing to vitamin O | publisher = John Wiley & Sons, Inc. | date = 2003 | location = Hoboken, New Jersey | pages = 1-253 | url = | doi = | id = | isbn = 0-471-43499-X }}</ref> [[Hemoglobin]] is weakly [[diamagnetic]], and is repulsed by magnetic fields. The magnets used are many orders of magnitude too weak to have any measurable effect on blood flow.<ref name='Stick_perfusion' />


== Description ==
== Description ==
The magnetic therapy industry totals sales of $300 million dollars per year in the United States <ref name=Finegold>{{cite journal | url=http://www.bmj.com/cgi/content/full/332/7532/4 | title=Magnet Therapy | author=Leonard Finegold | journal=British Medical Journal | year=2006 | volume=332 | issue=4 | doi=10.1136/bmj.332.7532.4 | pages = 4}}</ref>
The magnet therapy industry totals sales of $300 million dollars per year in the United States<ref name=Finegold>{{cite journal | url=http://www.bmj.com/cgi/content/full/332/7532/4 | title=Magnet Therapy | author=Leonard Finegold | journal=British Medical Journal | year=2006 | volume=332 | issue=4 | doi=10.1136/bmj.332.7532.4 | pages = 4}}</ref> and sells, often with explicit health claims, products such as magnetic bracelets and jewelry; magnetic straps for wrists, ankles, and the back; shoe insoles, mattresses, and magnetic blankets (blankets with magnets woven into the material); and even water that has been "magnetized".
and sells, often with explicit health claims, products such as magnetic bracelets and jewelry; magnetic straps for wrists, ankles, and the back; shoe insoles, mattresses, and magnetic blankets (blankets with magnets woven into the material); and even water that has been "magnetized".


=== Legal regulations ===
=== Legal regulations ===
Marketing of the therapy as an effective treatment is heavily restricted by law in many jurisdictions. In the United States, for example, [[FDA]] regulations prohibit marketing a magnet therapy product that claims to treat any "significant" condition such as cancer, HIV, AIDS, asthma, arthritis, or rheumatism.<ref>{{cite web | title = Magnets | work = CDRH Consumer Information | publisher = Food and Drug Administration | date = [[2000-03-01]] | url = http://www.fda.gov/cdrh/consumer/magnets.html | accessdate = 2007-02-02 }}</ref>
Marketing of any therapy as effective treatment for any condition is heavily restricted by law in many jurisdictions unless all such claims are scientifically validated. In the United States, for example, [[FDA]] regulations prohibit marketing any magnet therapy product using medical claims, as such claims are unfounded.<ref>{{cite web | title = Magnets | work = CDRH Consumer Information | publisher = Food and Drug Administration | date = [[2000-03-01]] | url = http://www.fda.gov/cdrh/consumer/magnets.html | accessdate = 2008-05-02}}</ref>


== Efficacy ==
== Efficacy ==
[[Double blind|Blinding]] of patients and assessors to the therapy is difficult since magnetization can be easily detected, ''e.g.'', by the attraction force it produces on [[ferrous]] objects.<ref>{{cite journal | last = Finegold, L. Flamm, B.| title = Magnet therapy | journal = British Medical Journal | volume = 332 | pages = 4 | url = http://bmj.bmjjournals.com/cgi/content/full/332/7532/4?ehom| date = 2006 | publisher = British Medical Association}}</ref> Incomplete or insufficient blinding tends to exaggerate treatment effects, particularly where any such effects are small.<ref name='CONSORT_2001'> {{cite journal|title=The revised CONSORT statement for reporting randomized trials: explanation and elaboration|journal=Annals of Internal Medicine|date=2001-04-17|first=DG|last=Altman|coauthors=KF Schulz, D Moher, M Egger, F Davidoff, D Elbourne, PC Gøtzsche, T Lang, CONSORT GROUP (Consolidated Standards of Reporting Trials)|volume=134|issue=8|pages=663-694|id=PMID 11304107 |url=http://www.ncbi.nlm.nih.gov/pubmed/11304107|format=|accessdate=2008-05-02 }}</ref> Several studies have been conducted in recent years to investigate what, if any, role static magnetic fields may play in health and healing.
Recent studies conducted by Dr. Thomas Skalak of the University of Virginia's Department of Biomedical Engineering has shown that moderate strength magnetic fields can reduce inflammation from injury in rats.<ref>{{cite web | title = Study | work = Acute Exposure to a Moderate Strength Magnetic Field Reduces Edema Formation in Rats | publisher = American Journal of Physiology | date = [[2007-11-01]] | url = http://ajpheart.physiology.org/cgi/content/abstract/00529.2007v1 | accessdate = 2008-02-29 }}</ref>

⚫
A study on humans of static field strengths up to 1 [[Tesla (unit)|T]] found no effect on local blood flow.<ref name='Stick_perfusion'> {{cite journal|title=Do strong static magnetic fields in NMR tomography modify tissue perfusion?|journal=Nuklearmedizin|date=1991|first=C.|last=Stick|coauthors=K. Hinkelmann, P, Eggert, H, Wendhausen|volume=154|issue=|pages=326|id= |url=|format=|accessdate=2008-03-12 }}</ref><ref name='Polk_handbook'>{{cite book | last = Polk | first = Charles | authorlink = | coauthors = Elliot Postow | title = Handbook of Biological Effects of Electromagnetic Fields | publisher = CRC Press | date = 1996 | location = | pages = 161 | url = | doi = | id = | isbn = 0849306418 }}</ref>


A trial of magnetic therapy for the treatment of wrist pain from [[carpal tunnel syndrome]] and chronic low back pain did not find any health benefits above placebo.<ref>Carter R, Aspy CB, Mold J. The effectiveness of magnet therapy for treatment of wrist pain attributed to carpal tunnel syndrome. J Fam Pract 2002;51: 38-40.</ref><ref>Collacott EA, Zimmerman JT, White DW, Rindone JP. Bipolar permanent magnets for the treatment of chronic low back pain: a pilot study. JAMA 2000;283: 1322-5.</ref>
A trial of magnetic therapy for the treatment of wrist pain from [[carpal tunnel syndrome]] and chronic low back pain did not find any health benefits above placebo.<ref>Carter R, Aspy CB, Mold J. The effectiveness of magnet therapy for treatment of wrist pain attributed to carpal tunnel syndrome. J Fam Pract 2002;51: 38-40.</ref><ref>Collacott EA, Zimmerman JT, White DW, Rindone JP. Bipolar permanent magnets for the treatment of chronic low back pain: a pilot study. JAMA 2000;283: 1322-5.</ref>


A 2003 [[Cochrane Library|Cochrane Review]] of carpal tunnel syndrome treatments found no improvement in symptoms over placebo or control.<ref name='Cochrane_carpal'> {{cite journal|title=Non-surgical treatment (other than steroid injection) for carpal tunnel syndrome|journal=Cochrane Database of Systematic Reviews|date=2003|first=D|last=O'Connor|coauthors=S Marshall, N Massy-Westropp|volume=2003|issue=1|pages=CD003219|id= {{doi|10.1002/14651858.CD003219}}|url=http://www.cochrane.org/reviews/en/ab003219.html|format=|accessdate=2008-05-02 }}</ref>
[[Double blind|Blinding]] the patients and the practitioners to the therapy is difficult since
magnetization can be easily detected, ''e.g.'', by the attraction force it produces on [[ferrous]] objects.<ref>{{cite journal | last = Finegold, L. Flamm, B.| title = Magnet therapy | journal = British Medical Journal | volume = 332 | pages = 4 | url = http://bmj.bmjjournals.com/cgi/content/full/332/7532/4?ehom| date = 2006 | publisher = British Medical Association}}</ref>


A randomized, double-blind, placebo controlled trial of 101 adults diagnosed with plantar heel pain carried out in year 2003 found no significant difference in outcome between use of active vs sham magnets.<ref>[http://jama.ama-assn.org/cgi/content/abstract/290/11/1474
⚫
A randomized controlled trial has found a statistically significant effect using non-magnetic and weak magnetic bracelets as controls against strong magnets.<ref>[http://www.bmj.com/cgi/content/abstract/329/7480/1450 Randomised controlled trial of magnetic bracelets for relieving pain in osteoarthritis of the hip and knee - Harlow et al. 329 (7480): 1450 - BMJ<!-- Bot generated title -->]</ref>
⚫
Effect of Magnetic vs Sham-Magnetic Insoles on Plantar Heel Pain], Mark H. Winemiller, MD; Robert G. Billow, DO; Edward R. Laskowski, MD; W. Scott Harmsen, MS; Journal of the American Medical Association</ref>
However, blinding was not perfect, as patients can assess the magnetic strength of the bracelets.


⚫
A randomized controlled trial has found a statistically significant effect using non-magnetic and weak magnetic bracelets as controls against strong magnets.<ref>[http://www.bmj.com/cgi/content/abstract/329/7480/1450 Randomised controlled trial of magnetic bracelets for relieving pain in osteoarthritis of the hip and knee - Harlow et al. 329 (7480): 1450 - BMJ<!-- (2004) Bot generated title -->]</ref> However, blinding was not perfect, as patients could assess the magnetic strength of the bracelets.
⚫
A study on humans of static field strengths up to 1 [[Tesla (unit)|T]] found no effect on local blood flow.<ref name='Stick_perfusion'> {{cite journal|title=Do strong static magnetic fields in NMR tomography modify tissue perfusion?|journal=Nuklearmedizin|date=1991|first=C.|last=Stick|coauthors=K. Hinkelmann, P, Eggert, H, Wendhausen|volume=154|issue=|pages=326|id= |url=|format=|accessdate=2008-03-12 }}</ref><ref name='Polk_handbook'>{{cite book | last = Polk | first = Charles | authorlink = | coauthors = Elliot Postow | title = Handbook of Biological Effects of Electromagnetic Fields | publisher = CRC Press | date = 1996 | location = | pages = 161 | url = | doi = | id = | isbn = 0849306418 }}</ref>


== Criticism ==
== Criticism ==
In certain cases, there is limited scientific theory under which the claimed benefits of magnet therapy might act. A 2002 [[National Science Foundation|NSF]] report on public attitudes and understanding of science noted that magnet therapy is "not at all scientific."<ref name='mag_NSF'>{{cite book | last = National Science Board | first = | authorlink = National Science Foundation | coauthors = | title = Science and Engineering Indicators – 2002 | publisher = National Science Foundation | date = 2002 | location = Arlington, VA | pages = ch. 7 | url = http://www.nsf.gov/statistics/seind02/c7/c7s5.htm | doi = | id = | isbn = 978-0160665790 }} "Among all who had heard of [magnet therapy], 14 percent said it was very scientific and another 54 percent said it was sort of scientific. Only 25 percent of those surveyed answered correctly, that is, that it is not at all scientific." </ref> A randomized, double-blind, placebo controlled trial of 101 adults diagnosed with plantar heel pain carried out in year 2003 found no significant difference in outcome between use of active vs sham magnets.<ref>[http://jama.ama-assn.org/cgi/content/abstract/290/11/1474
A 2002 [[National Science Foundation|NSF]] report on public attitudes and understanding of science noted that magnet therapy is "not at all scientific."<ref name='mag_NSF'>{{cite book | last = National Science Board | first = | authorlink = National Science Foundation | coauthors = | title = Science and Engineering Indicators – 2002 | publisher = National Science Foundation | date = 2002 | location = Arlington, VA | pages = ch. 7 | url = http://www.nsf.gov/statistics/seind02/c7/c7s5.htm | doi = | id = | isbn = 978-0160665790 }} "Among all who had heard of [magnet therapy], 14 percent said it was very scientific and another 54 percent said it was sort of scientific. Only 25 percent of those surveyed answered correctly, that is, that it is not at all scientific." </ref>

⚫
Effect of Magnetic vs Sham-Magnetic Insoles on Plantar Heel Pain], Mark H. Winemiller, MD; Robert G. Billow, DO; Edward R. Laskowski, MD; W. Scott Harmsen, MS; Journal of the American Medical Association</ref>
A number of vendors make unsupported claims about magnet therapy by using pseudoscientific and new-age language. Such claims are criticized by skeptics.<ref>[http://www.csicop.org/si/9807/magnet.html Magnetic Therapy: Plausible Attraction?] by [[James D. Livingston]] &mdash; a [[Skeptical Inquirer]] article</ref>
A number of vendors make unsupported claims about magnet therapy by using pseudoscientific and new-age language. Such claims are criticized by skeptics.<ref>[http://www.csicop.org/si/9807/magnet.html Magnetic Therapy: Plausible Attraction?] by [[James D. Livingston]] &mdash; a [[Skeptical Inquirer]] article</ref>
Most criticisms include:
Most criticisms include:


* The typical magnet used produces insufficient [[magnetic field]] to have any effect on muscle tissue, bones, blood vessels, or organs.<ref>{{cite book | last = Park | first = Robert L. | authorlink = Robert L. Park | coauthors = | title = Voodoo Science: The Road from Foolishness to Fraud | publisher = Oxford University Press | date = 2000 | location = New York, New York | pages = 58-63 | url = | doi = | id = | isbn = 0-19-513515-6 "Not only are magnetic fields of no value in healing, you might characterize these as "homeopathic" magnetic fields."}}</ref>
* The typical magnet used produces insufficient [[magnetic field]] to have any effect on muscle tissue, bones, blood vessels, or organs.<ref name=Park_Voodoo>{{cite book | last = Park | first = Robert L. | authorlink = Robert L. Park | coauthors = | title = Voodoo Science: The Road from Foolishness to Fraud | publisher = Oxford University Press | date = 2000 | location = New York, New York | pages = 58-63 | url = | doi = | id = | isbn = 0-19-513515-6 "Not only are magnetic fields of no value in healing, you might characterize these as "homeopathic" magnetic fields."}}</ref>
* Some manufacturers claim that the magnets help to circulate the blood by interacting with the iron in [[hemoglobin]], a major component of [[red blood cell]]s. However in its ionised form, iron is not [[ferromagnetic]] and would not be subject to magnetic attraction,<ref>[http://www.radiologyinfo.org/content/safety/mri_safety.htm Safety in Medical Imaging Procedures<!-- Bot generated title -->]</ref> save for [[magnetohydrodynamic]] forces due to its charge.
* Some manufacturers claim that the magnets help to circulate the blood by interacting with the iron in [[hemoglobin]], a major component of [[red blood cell]]s. There is no indication that circulatory benefits would result even if some blood component were to couple strongly to magnetic fields.
* Others claim that the magnets can restore the body's theorized "electromagnetic energy balance", but no such balance is medically recognized.
* Others claim that the magnets can restore the body's theorized "electromagnetic energy balance", but no such balance is medically recognized.
* Even in the many times stronger magnetic fields used in [[magnetic resonance imaging]], none of the claimed effects are observed.<ref>[http://www.radiologyinfo.org/content/safety/mri_safety.htm Safety in Medical Imaging Procedures]</ref>
* There are claims that the south pole of a magnet acts differently on the body than the north pole.<ref>[http://www.magno-pulse.com/restless_legs.php#introduction Magnopulse LTD<!-- Bot generated title -->]</ref>
* There are claims that the south pole of a magnet acts differently on the body than the north pole.<ref>[http://www.magno-pulse.com/restless_legs.php#introduction Magnopulse LTD<!-- Bot generated title -->]</ref>
* Many of the websites that provide information and resources promoting the benefits of magnetic therapy belong to individuals and companies that profit from the sale of magnetic therapy products.
* Many of the websites that provide information and resources promoting the benefits of magnetic therapy belong to individuals and companies that profit from the sale of magnetic therapy products.

Revision as of 22:28, 2 May 2008

Magnet therapy, magnetic therapy, magnetotherapy or magnotherapy is a complementary and alternative medicine practice involving the use of static magnetic fields. Practitioners claim that subjecting certain parts of the body to magnetostatic fields produced by permanent magnets has beneficial health effects. Magnet therapy is considered pseudoscientific due to both physical and biological implausibility, as well as a lack of any established effect on health or healing.[1][2] Hemoglobin is weakly diamagnetic, and is repulsed by magnetic fields. The magnets used are many orders of magnitude too weak to have any measurable effect on blood flow.[3]

Description

The magnet therapy industry totals sales of $300 million dollars per year in the United States[4] and sells, often with explicit health claims, products such as magnetic bracelets and jewelry; magnetic straps for wrists, ankles, and the back; shoe insoles, mattresses, and magnetic blankets (blankets with magnets woven into the material); and even water that has been "magnetized".

Legal regulations

Marketing of any therapy as effective treatment for any condition is heavily restricted by law in many jurisdictions unless all such claims are scientifically validated. In the United States, for example, FDA regulations prohibit marketing any magnet therapy product using medical claims, as such claims are unfounded.[5]

Efficacy

Blinding of patients and assessors to the therapy is difficult since magnetization can be easily detected, e.g., by the attraction force it produces on ferrous objects.[6] Incomplete or insufficient blinding tends to exaggerate treatment effects, particularly where any such effects are small.[7] Several studies have been conducted in recent years to investigate what, if any, role static magnetic fields may play in health and healing.

A study on humans of static field strengths up to 1 T found no effect on local blood flow.[3][8]

A trial of magnetic therapy for the treatment of wrist pain from carpal tunnel syndrome and chronic low back pain did not find any health benefits above placebo.[9][10]

A 2003 Cochrane Review of carpal tunnel syndrome treatments found no improvement in symptoms over placebo or control.[11]

A randomized, double-blind, placebo controlled trial of 101 adults diagnosed with plantar heel pain carried out in year 2003 found no significant difference in outcome between use of active vs sham magnets.[12]

A randomized controlled trial has found a statistically significant effect using non-magnetic and weak magnetic bracelets as controls against strong magnets.[13] However, blinding was not perfect, as patients could assess the magnetic strength of the bracelets.

Criticism

A 2002 NSF report on public attitudes and understanding of science noted that magnet therapy is "not at all scientific."[14]

A number of vendors make unsupported claims about magnet therapy by using pseudoscientific and new-age language. Such claims are criticized by skeptics.[15] Most criticisms include:

  • The typical magnet used produces insufficient magnetic field to have any effect on muscle tissue, bones, blood vessels, or organs.[1]
  • Some manufacturers claim that the magnets help to circulate the blood by interacting with the iron in hemoglobin, a major component of red blood cells. There is no indication that circulatory benefits would result even if some blood component were to couple strongly to magnetic fields.
  • Others claim that the magnets can restore the body's theorized "electromagnetic energy balance", but no such balance is medically recognized.
  • Even in the many times stronger magnetic fields used in magnetic resonance imaging, none of the claimed effects are observed.[16]
  • There are claims that the south pole of a magnet acts differently on the body than the north pole.[17]
  • Many of the websites that provide information and resources promoting the benefits of magnetic therapy belong to individuals and companies that profit from the sale of magnetic therapy products.

See also

References

  1. ^ a b Park, Robert L. (2000). Voodoo Science: The Road from Foolishness to Fraud. New York, New York: Oxford University Press. pp. 58–63. ISBN 0-19-513515-6 "Not only are magnetic fields of no value in healing, you might characterize these as "homeopathic" magnetic fields.". {{cite book}}: Check |isbn= value: invalid character (help); Cite has empty unknown parameter: |coauthors= (help)
  2. ^ Wanjek, Christopher (2003). Bad Medicine: misconceptions and misuses revealed from distance healing to vitamin O. Hoboken, New Jersey: John Wiley & Sons, Inc. pp. 1–253. ISBN 0-471-43499-X. {{cite book}}: Cite has empty unknown parameter: |coauthors= (help)
  3. ^ a b Stick, C. (1991). "Do strong static magnetic fields in NMR tomography modify tissue perfusion?". Nuklearmedizin. 154: 326. {{cite journal}}: |access-date= requires |url= (help); Unknown parameter |coauthors= ignored (|author= suggested) (help)
  4. ^ Leonard Finegold (2006). "Magnet Therapy". British Medical Journal. 332 (4): 4. doi:10.1136/bmj.332.7532.4.
  5. ^ "Magnets". CDRH Consumer Information. Food and Drug Administration. 2000-03-01. Retrieved 2008-05-02. {{cite web}}: Check date values in: |date= (help)
  6. ^ Finegold, L. Flamm, B. (2006). "Magnet therapy". British Medical Journal. 332. British Medical Association: 4.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  7. ^ Altman, DG (2001-04-17). "The revised CONSORT statement for reporting randomized trials: explanation and elaboration". Annals of Internal Medicine. 134 (8): 663–694. PMID 11304107. Retrieved 2008-05-02. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
  8. ^ Polk, Charles (1996). Handbook of Biological Effects of Electromagnetic Fields. CRC Press. p. 161. ISBN 0849306418. {{cite book}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
  9. ^ Carter R, Aspy CB, Mold J. The effectiveness of magnet therapy for treatment of wrist pain attributed to carpal tunnel syndrome. J Fam Pract 2002;51: 38-40.
  10. ^ Collacott EA, Zimmerman JT, White DW, Rindone JP. Bipolar permanent magnets for the treatment of chronic low back pain: a pilot study. JAMA 2000;283: 1322-5.
  11. ^ O'Connor, D (2003). "Non-surgical treatment (other than steroid injection) for carpal tunnel syndrome". Cochrane Database of Systematic Reviews. 2003 (1): CD003219. doi:10.1002/14651858.CD003219. Retrieved 2008-05-02. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
  12. ^ [http://jama.ama-assn.org/cgi/content/abstract/290/11/1474 Effect of Magnetic vs Sham-Magnetic Insoles on Plantar Heel Pain], Mark H. Winemiller, MD; Robert G. Billow, DO; Edward R. Laskowski, MD; W. Scott Harmsen, MS; Journal of the American Medical Association
  13. ^ Randomised controlled trial of magnetic bracelets for relieving pain in osteoarthritis of the hip and knee - Harlow et al. 329 (7480): 1450 - BMJ
  14. ^ National Science Board (2002). Science and Engineering Indicators – 2002. Arlington, VA: National Science Foundation. pp. ch. 7. ISBN 978-0160665790. {{cite book}}: Cite has empty unknown parameter: |coauthors= (help) "Among all who had heard of [magnet therapy], 14 percent said it was very scientific and another 54 percent said it was sort of scientific. Only 25 percent of those surveyed answered correctly, that is, that it is not at all scientific."
  15. ^ Magnetic Therapy: Plausible Attraction? by James D. Livingston — a Skeptical Inquirer article
  16. ^ Safety in Medical Imaging Procedures
  17. ^ Magnopulse LTD

External links

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