Questions about magnetic therapy for pain relief and other health
problems are answered by the U.S. National Center for Complementary
and Alternative Medicine at:
http://nccam.nih.gov/health/magnet/magnet.htm .
Extracts below...

3. What is the history of the discovery and use of magnets to treat
pain?
Magnets have been used for many centuries in attempts to treat
pain.a By various accounts, this use began when people first noticed
the presence of naturally magnetized stones, also called lodestones.
Other accounts trace the beginning to a shepherd noticing that the
nails in his sandals were pulled out by some stones. By the third
century A.D., Greek physicians were using rings made of magnetized
metal to treat arthritis and pills made of magnetized amber to stop
bleeding. In the Middle Ages, doctors used magnets to treat gout,
arthritis, poisoning, and baldness; to probe and clean wounds; and
to retrieve arrowheads and other iron-containing objects from the
body.

In the United States, magnetic devices (such as hairbrushes and
insoles), magnetic salves, and clothes with magnets applied came
into wide use after the Civil War, especially in some rural areas
where few doctors were available. Healers claimed that magnetic
fields existed in the blood, organs, or elsewhere in the body and
that people became ill when their magnetic fields were depleted.
Thus, healers marketed magnets as a means of "restoring" these
magnetic fields. Magnets were promoted as cures for paralysis,
asthma, seizures, blindness, cancer, and other conditions. The use
of magnets to treat medical problems remained popular well into the
20th century. More recently, magnets have been marketed for a wide
range of diseases and conditions, including pain, respiratory
problems, high blood pressure, circulatory problems, arthritis,
rheumatism, and stress.

4. How common is the use of magnets to treat pain?
A 1999 survey of patients who had rheumatoid arthritis,
osteoarthritis, or fibromyalgia and were seen by rheumatologists
reported that 18 percent had used magnets or copper bracelets, and
that this was the second-most-used CAM therapy by these patients,
after chiropractic.6 One estimate places Americans' spending on
magnets to treat pain at $500 million per year; the worldwide
estimate is $5 billion.7 Many people purchase magnets in stores or
over the Internet to use on their own without consulting a health
care provider.

5. What are some examples of theories and beliefs about magnets and
pain?
Some examples of theories and beliefs about using magnets to treat
pain are listed below. These range from theories proposed by
scientific researchers to claims made by magnet manufacturers. It is
important to note that while the results for some of the findings
from the scientific studies have been intriguing, none of the
theories or claims below has been conclusively proven. For the
following, summaries of research from peer-reviewed medical and
scientific journals appear in Appendix I:

Static magnets might change how cells function.

Magnets might alter or restore the equilibrium (balance) between
cell death and growth.

Because it contains iron, blood might act as a conductor of magnetic
energy. Static magnets might increase the flow of blood and,
therefore, increase the delivery of oxygen and nutrients to tissues.

Weak pulsed electromagnets might affect how nerve cells respond to
pain.

Pulsed electromagnets might change the brain's perception of pain.

Electromagnets might affect the production of white blood cells
involved in fighting infection and inflammation.
Here are two other theories and beliefs:

Magnets might increase the temperature of the area of the body being
treated.

"Magnetizing" or "re-magnetizing" drinking water or other beverages
might allow them to hydrate the body better and flush out
more "toxins" than ordinary drinking water.


6. How are static magnets used in attempts to treat pain?
Static magnets are usually made from iron, steel, rare-earth
elements, or alloys. Typically, the magnets are placed directly on
the skin or placed inside clothing or other materials that come into
close contact with the body. Static magnets can be unipolar (one
pole of the magnet faces or touches the skin) or bipolar (both poles
face or touch the skin, sometimes in repeating patterns).8 Some
magnet manufacturers make claims about the poles of magnets--for
example, that a unipolar design is better than a bipolar design, or
that the north pole gives a different effect from the south pole.
These claims have not been scientifically proven.1,9

A small number of rigorous scientific studies have examined the
efficacy of static magnets in treating pain. This evidence is
discussed in Question 8 and Appendices II and III.

7. How are electromagnets used in attempts to treat pain?
Electromagnets were approved by the FDA in 1979 to treat bone
fractures that have not healed well.2,3 Researchers have been
studying electromagnets for painful conditions, such as knee pain
from osteoarthritis, chronic pelvic pain, problems in bones and
muscles, and migraine headaches.3,9-12 However, these uses of
electromagnets are still considered experimental by the FDA and have
not been approved. Currently, electromagnets to treat pain are being
used mainly under the supervision of a health care provider and/or
in clinical trials.

An electromagnetic therapy called TMS (transcranial magnetic
stimulation) is also being studied by researchers. In TMS, an
insulated coil is placed against the head, near the area of the
brain to be examined or treated, and an electrical current generates
a magnetic field into the brain. Currently, TMS is most often used
as a diagnostic tool, but research is also under way to see whether
it is effective in relieving pain.13,14 A type of TMS called rTMS
(repetitive TMS) is believed by some to produce longer lasting
effects and is being explored for its usefulness in treating chronic
pain, facial pain, headache, and fibromyalgia pain.15,16 A related
form of electromagnetic therapy is rMS (repetitive magnetic
stimulation). It is similar to rTMS except that the magnetic coil is
placed on or near a painful area of the body other than the head.
This therapy is being studied as a treatment for musculoskeletal
pain.17,18


8. What is known from the scientific evidence about the
effectiveness of magnets in treating pain?
Overall, the research findings so far do not firmly support claims
that magnets are effective for treatment of pain.

Findings from Reviews of Scientific Studies

Reviews take a broad look at the findings from a group of individual
research studies. Such reviews are usually either a general review,
a systematic review, or a meta-analysis. There are not many reviews
available on CAM uses of magnets to treat pain. Appendix II provides
examples of six reviews published from August 1999 through August
2003 in English in the National Library of Medicine's MEDLINE
database.

Often, these reviews compared what is known from the clinical trials
of magnets for painful conditions to what is known from conventional
treatments or from other CAM treatments for the same condition(s).


One review found that static magnetic therapy may work for certain
conditions but that there is not adequate scientific support to
justify its use.1


Three reviews found that electromagnetic therapy showed promise for
the treatment of some, but not all, painful conditions, and that
more research is needed.9,19,20 One of these reviews also looked at
two randomized clinical trials (RCTs) of static magnets.9 One
reported significant pain relief in subjects using magnets, but the
other did not.


Another review concluded that TMS has an effect on the central
nervous system that might relieve chronic pain and, therefore,
should be studied further.14


The remaining review found no studies on magnets for neck pain and
stated that rigorous studies are much needed.21


It is important to note that the reviews pointed out problems with
the rigor of most research on magnets for pain.9,14,19,20 For
example, many of the clinical trials involved a very small number of
participants, were conducted for very short durations (e.g., one
study applied a magnet a total of one time for 45 minutes), and/or
lacked a placebo or sham group for comparison to the magnet
group.19,20 Thus, the results of many trials may not be truly
meaningful. Most reviews stated that more and better quality
research is needed before magnets' effectiveness can be adequately
judged.

Findings from Clinical Trials

The studies in Appendix III give an overview of scientific research
from 15 RCTs published in English from January 1997 through March
2004 and cataloged in the National Library of Medicine's MEDLINE
database. These trials studied CAM uses of static magnets or
electromagnets for various kinds of pain.

The results of trials of static magnets have been conflicting. Four
of the nine static magnet trials analyzed found no significant
difference in pain relief from using a magnet compared with sham
treatment or usual medical care.7,8,22,23 Four trials did find a
significant difference, with greater benefit seen from magnets.24-27
The remaining trial compared only a weaker strength magnet to a
stronger magnet, and found benefit from both (there was no
difference between groups in how much benefit).28


Trials of electromagnets yielded more consistent results. Five out
of six trials found that these magnets significantly reduced
pain.10,11,17,18,29 The sixth found a significant benefit to
physical function from using electromagnets, but not to pain or
stiffness.30


Some study authors suggested that a placebo effect could have been
responsible for the pain relief that occurred from magnets.22,30

While criticizing many of these studies, it is fair to say that
testing magnets in clinical trials has presented challenges. For
example, it can be difficult to design a sham magnet that appears
exactly like an active magnet. Also, there has been concern about
how many participants have tried to determine whether they have been
assigned an active magnet (for example, by seeing whether a
paperclip would be attracted to it); this knowledge could affect how
meaningful a trial's results are.
Top

9. Are there scientific controversies associated with using magnets
for pain?
Yes, there are many controversies. Examples include:

The mechanism(s) by which magnets might relieve pain have not been
conclusively identified or proven.

Pain relief while using a magnet may be due to reasons other than
the magnet. For example, there could be a placebo effect or the
relief could come from whatever holds the magnet in place, such as a
warm bandage or a cushioned insole.22,24

Opinions differ among manufacturers, health care providers who use
magnetic therapy, and others about which types of magnets (strength,
polarity, length of use, and other factors) should be used and how
they should be used in studies to give the most definitive answers.

Actual magnet strengths can vary (sometimes widely) from the
strengths claimed by manufacturers. This can affect scientists'
ability to reproduce the findings of other scientists and consumers'
ability to know what strength magnet they are actually using.

10. Have any side effects or complications occurred from using
magnets for pain?
The kinds of magnets marketed to consumers are generally considered
to be safe when applied to the skin.7 Reports of side effects or
complications have been rare. One study reported that a small
percentage of participants had bruising or redness on their skin
where a magnet was worn.33

Manufacturers often recommend that static magnets not be used by the
following people1:

Pregnant women, because the possible effects of magnets on the fetus
are not known.

People who use a medical device such as a pacemaker, defibrillator,
or insulin pump, because magnets may affect the magnetically
controlled features of such devices.

People who use a patch that delivers medication through the skin, in
case magnets cause dilation of blood vessels, which could affect the
delivery of the medicine. This caution also applies to people with
an acute sprain, inflammation, infection, or wound.
There have been rare cases of problems reported from the use of
electromagnets. Because at present these are being used mainly under
the supervision of a health care provider and/or in clinical trials,
readers are advised to consult their provider about any questions.

11. What should consumers know if they are considering using magnets
to treat pain?
It is important that people inform all their health care providers
about any therapy they are using or considering, including magnetic
therapy. This is to help ensure a safe and coordinated plan of care.

In the studies that did find benefits from magnetic therapy, many
have shown those benefits very quickly. This suggests that if a
magnet does work, it should not take very long for the user to start
noticing the effect. Therefore, people may wish to purchase magnets
with a 30-day return policy and return the product if they do not
get satisfactory results within 1 to 2 weeks.

If people decide to use magnets and they experience side effects
that concern them, they should stop using the magnets and contact
their health care providers.

Consumers who are considering magnets, whether for pain or other
conditions, can consult the free publications prepared by Federal
Government agencies. See "For More Information."
If You Buy a Magnet…

Check on the company's reputation with consumer protection agencies.
Watch for high return fees. If you see them before purchase, ask
that they be dropped and obtain written confirmation that they will
be.
Pay by credit card if possible. This offers you more protection if
there is a problem.
If you buy from sources (such as Web sites) that are not based in
the United States, U.S. law can do little to protect you if you have
a problem related to the purchase.
Sources: The FDA and the Pennsylvania Medical Society


12. Is the National Center for Complementary and Alternative
Medicine (NCCAM) funding research on magnets for pain and other
diseases and conditions?
Yes. For example, recent projects supported by NCCAM include:

Static magnets, for fibromyalgia pain and quality of life
Pulsed electromagnets, for migraine headache pain
Static magnets, for their effects on networks of blood vessels
involved in healing TMS, for Parkinson's disease
Electromagnets, for their effects on injured nerve and muscle cells
In addition, the papers by Alfano et al.,26 Swenson,21 and Wolsko et
al.27 report on research funded by NCCAM.
----------------------
Cambridge Healing - Holistic Lifestyle:
http://health.groups.yahoo.com/group/cheal/