TORONTO - They're embedded in everything from mattresses to insoles for shoes to wrist bands - but there is no definitive scientific evidence that static magnets actually relieve chronic pain, researchers say.
Products that incorporate static magnets are a multibillion-dollar business worldwide and many chronic pain sufferers are drawn to the promise they hold for alleviating such nagging conditions as arthritis, fibromyalgia and low back discomfort.
The theory from proponents is that the device's magnetic field increases blood flow, causing increased oxygen, nutrients, hormones and painkilling endorphins to be distributed to tissues in the affected area.
So researchers at the Complementary Medicine, Peninsula Medical School, at the Universities of Exeter and Plymouth decided to search the medical literature to determine whether there is any proof magnets can actually reduce pain.
In their analysis of nine randomized trials comparing products containing magnets with those containing either no magnet or very weak ones, the researchers found that the data did not support the use of the alternative therapy for pain control.
"There is no definite grounds of being absolutely sure that a magnet works or not," lead author Dr. Max Pittler, a complementary medicine specialist, said Monday from Exeter, England.
"The evidence does not support the use of static magnets for pain relief and therefore magnets cannot be recommended as an effective treatment," he said. The analysis is published in Tuesday's Canadian Medical Association Journal.
However, Pittler acknowledged that the findings also mean that magnets could work - but the clinical trials weren't able to prove that either. In part, that's because pain measurements are subjective - subjects self-report pain levels - and individual studies in the analysis may have been too small to provide statistically relevant results.
Still, Pittler said the biggest concern is that people seeking to ease their pain may be buying into - and paying big bucks - for a therapy that may not be effective.
"It is important to realize that this is a situation where there is a huge market out there," he said. "In a situation where you don't have rigorous data . . . patients are putting their hopes into a magnet and spending a lot of money on it."
He suggests many pain sufferers would be better off taking an over-the-counter painkiller such as ASA or acetaminophen.
"Or if patients are keen on trying complementary medicine for certain pain conditions, there is some data available that acupuncture might alleviate some of the pain they feel," Pittler said. "Acupuncture might be one complementary therapy in certain pain conditions," such as osteoarthritis.
Health Canada considers claims for specific therapeutic benefits of static magnets to be unfounded, a spokeswoman for the federal department said by e-mail Monday. "These claims include, but are not limited to: pain relief, increased blood circulation, increased oxygenation, reduction of high blood pressure, stimulation of the immune system and the treatment of sleep disorders, infections, depression, erectile dysfunction, rheumatoid disease and cancer."
A static magnet promoted for any of these purposes is considered a violation of the Food and Drugs Act or Medical Devices Regulations.
Commenting on the analysis, naturopath Kieran Cooley agreed that magnets wouldn't be high on the list of possible therapies to treat chronic pain.
"I don't think naturopaths overall would be strong advocates of magnetic therapy if (patients) hadn't already tried other modalities like acupuncture or other pain-specific treatments for what they're going through, whether it's fibromyalgia, chronic fatigue syndrome or even acute back pain," said Cooley, a researcher and assistant professor at the Canadian College of Naturopathic Medicine in Toronto.
"Acupuncture is probably the biggest one. Mild to moderate exercise has actually been shown to have the best effect on pain overall of any sort of therapy you can use, even conventional drugs or over-the-counter pain medications like Advil or Aspirin."
Yet magnets can't be written off completely until more definitive evidence on their effectiveness or lack of effectiveness is obtained, Cooley conceded. "There are clearly some people (in the British analysis) who are benefiting from the therapy. There are other people who are not benefiting very much and a few people who seem to be getting worse."
"So in that respect, magnet therapy is definitely a buyer-beware or consumer-beware kind of industry."
