Results from a University of York study showed using hands-free headsets reduce cell phone radiation by as much as 47%. The study, part of the UK's Mobile Telecommunications Health Research program, concluded that radiation was cut by nearly half when using a wired hands-free kit running up from the torso, rather than directly talking on a phone against the head.

Dr. Stuart Porter, from the Department of Electronics at the University of York said, "The previous work on measuring the effect of hands-free kits was inconclusive and their methodology was not subjected to scrutiny by independent academics."

"From our perspective, we are not saying use hands-free kits because mobile phones are unsafe, but if people are concerned about potential risks there may be some value from a precautionary approach."

By using a model human head containing a liquid, which measured the specific absorption rate (SAR), Dr. Porter and his colleagues used seven cell phones and probes to measure the electrical currents created by wires from the hands-free kits.

Conflicting reports in the past have suggested that using a hands-free headset may increase emissions to the brain, while others have concluded the opposite.

"These results show that hands-free kits reduce SAR values," said Dr. Michael Clark, member of the National Radiological Protection Board. "Some results reported in 2000 claimed that SARs were increased by hands-free kits. This was hard to fathom at the time, and this work from York refutes that finding."

These conclusions come after last week's precaution advising the public to restrict cell phone usage for children, which could harm developing brains.