January 7, 2006
A Warning About Magnet Therapy
It doesn't work, physician and a physicist say; others disagree
The magnets advertised in magazines and on the Internet to treat health problems, particularly pain, offer no proven benefit, a physicist and a physician contend.
"Magnets are touted by successful athletes, allowed to be widely advertised, and sold without restrictions, so it is not surprising that lay people think that claims of therapeutic efficacy are reasonable," claims an editorial in the Jan. 7 issue of the British Medical Journal. It was written by Leonard Finegold, a professor of physics at Drexel University in Philadelphia, and Dr. Bruce L. Flamm, a physician in obstetrics and gynecology at the Kaiser Permanente Medical Center in Riverside, Calif.
Yet, "if there is any healing effect of magnets, it is apparently small since published research, both theoretical and experimental, is weighted heavily against any therapeutic benefit," they wrote.
Finegold said he enlisted Flamm in writing the warning "because I wanted a physician's point of view, and we had corresponded about other things."
Finegold and Flamm said they're upset about the amount of money spent on magnetic bracelets, insoles, wrist and knee bands, back and neck braces, and even pillows and mattresses -- an estimated $300 million a year in the United States, and $1 billion worldwide.
They're also concerned about scientifically designed, controlled studies claiming to show that magnetic therapy can provide benefit for conditions such as carpal tunnel syndrome and arthritis. It's almost impossible to conduct a "double-blind" study in which both the physician and the patient are unaware of who is getting the real treatment, because the presence of magnets is always obvious, they wrote.
And they worry that self-treatment with magnetic therapy "may result in an underlying medical condition being left untreated."
But Dr. Michael I. Weintraub, a clinical professor of neurology and internal medicine at New York Medical College in Valhalla, N.Y., disagrees with that conclusion.
Weintraub, who has done extensive studies of magnetic therapy, agreed "there have been numerous bogus claims about magnetotherapy", and some items being sold to the public are worthless. But "all magnets are not equal," he said, and the proper magnet used properly for the proper period of time can be effective in some conditions.
Weintraub said he has done the kind of controlled study, which is considered the gold standard of medical research, on magnetic therapy for several conditions, including diabetic peripheral neuropathy, in which nerves gradually die. A study of 375 diabetics who wore a magnetic device for one month (with control subjects who wore a sham device) showed "benefits equal to or better than that from drugs," he said.
One point against magnetic therapy made in the Finegold-Flamm editorial is that magnetic resonance imaging devices, which use extremely powerful magnets, "show neither ill nor healing effects." Weintraub disputes that contention, too.
A study he did involving 1,000 individuals exposed to magnetic resonance imaging found that "a significant number of cases, 18 to 20 percent," did report negative effects, such as a metallic taste in the mouth or worsening of some symptoms. A report on that study has been submitted to a journal for publication, Weintraub said.
Flamm conceded that it's possible magnets can have a physical effect, because a changing magnetic field can create electricity and heat. "There may be something there," he said.
"But what we know pretty much for sure is that the claims everything they are selling on the Internet appear to be totally baseless," Flamm said.
Finegold had financial advice for anyone thinking about buying such a device: "If you want to use a magnet, buy the cheapest. It will relieve the pain in your wallet."
Questions about magnetic therapy for pain are answered by the National Center for Complementary and Alternative Medicine (http://nccam.nih.gov ).