MADISON, United States (AFP) - Spreading honey on a diabetic ulcer could prevent the need to amputate an infected foot, researchers say.

A doctor at the University of Wisconsin who helped about half a dozen of her diabetic patients avoid amputation has launched a controlled trial to promote the widespread use of honey therapy.

The therapy involves squeezing a thick layer of honey onto the wound after dead skin and bacteria have been removed.

The honey kills bacteria because it is acidic and avoids the complication of bacterial resistance found with standard antibiotics, Jennifer Eddy, a professor at the University's School of Medicine and Public Health, told AFP.

"This is a tremendously important issue for world health," Eddy said.

Diabetics typically have poor circulation and decreased ability to fight infection and ulcers can be hard to treat. An amputation is performed every 30 seconds somewhere in the world, Eddy said.

"If we can prove that honey promotes healing in diabetic ulcers, we can offer new hopes for many patients, not to mention the cost benefit, and the issue of bacterial resistance. The possibilities are tremendous."

Honey therapy is already used to treat bed sores in New Zealand and as an alternative form of medicine in Europe, but has largely been relegated to history books in the United States.

Eddy first heard of it in medical school when a professor commented that of all the ancient remedies, honey actually seemed to work when he tried it out in the laboratory.

She tried honey therapy as a last resort six years ago with a 79-year-old diabetic patient who had developed foot wounds resistant to standard treatments. 

"I tried it only after everything else had failed and... we had essentially sent him home to die," she said. "All antibiotics were stopped when we started honey, and his wounds rapidly healed." 

Eddy hopes to have the trial completed and the results published by 2008 or 2009.