"Studies have shown that magnetic field therapy facilitates healing of broken bones by stimulating circulation and bone growth," says Hans-Ulrich Jabs, an internist in the German town of Nottuln and head of the medicine and wellness section of the Duesseldorf- based German Wellness Association.

The physics of the therapy is as follows: When electricity flows through a conductor, a magnetic field, with concentric lines of force, forms around it. Such a magnetic field - produced by a solenoid, magnetic-field device, or other magnetic object - is used to rectify, as it were, the reduced and impaired electrical tension in the cells of an unwell body.

Depending on their strength, magnetic fields can penetrate bodily structures and stimulate cells, according to Jabs. The procedure is said to boost cellular metabolism, accelerate healing, and strengthen the entire body's natural defenses.

The Munich-based German Society of Physical Medicine and Rehabilitation (DGPMR) is skeptical of such claims, however, saying there is still no sufficient proof of the efficacy of magnetic field therapy.

"Aside from isolated experiments, magnetic field therapy has been unable to take hold at university hospitals and in medical textbooks during the past 30 years," said Professor Peter Kroeling, the DGPMR's second vice-president. "Therefore we continue to consider it an outsider method."

But some physicians and wellness experts are convinced of its usefulness as a supplementary therapy. When employed correctly, it is particularly helpful in orthopedics - in treating arthrosis, for example, said Jabs.

"Pulsating magnetic fields with alternating frequencies have been shown to facilitate the growth of damaged cartilage and alleviate pain," he said.

Magnetic fields are also used in psychiatry. "Repetitive Transcranial Magnetic Stimulation, or RTMS for short, influences the activity of nerve cells," Thomas Wobrock, head physician at Goettingen University's psychiatry and psychotherapy clinic, explained. He pointed out that there were clear indications of restricted activity in the frontal cortex of a depressed person.

But Wobrock warned against exaggerated hopes. The therapy, he said, was not superior to treatment with drugs, although it could be considered a useful supplement.