Study shows cell phones have metabolic effect on brain

Cell phones are almost everywhere these days, right next to the ears of people who rely on them, but little is understood about the potentially harmful effects of radio-frequency signals on the brain.

Researchers monitored 47 healthy people over one year for a study in the Journal of the American Medical Association. Participants had cell phones placed on their left and right ears in 50-minute increments. One was activated but muted; the other was off. Then they were tested with both phones turned off.

Researchers used sophisticated brain imaging to monitor the amount of glucose consumed in the brain during these tests.

"(Glucose is) a very sensitive marker to indicate if there are changes in brain activity that may be driven by a given stimulus, which in this case was the cell phone," said Dr. Nora D. Volkow from the National Institute on Drug Abuse in Bethesda, Md.

"Exposure to a cell phone was associated with increases in glucose consumption by the brain, which indicates that the brain was being activated by the radio frequencies from the cell phone," Volkow said.

The side of the brain closest to the antenna had the largest increase in metabolism. The frequencies are very weak, but they do have a metabolic effect on the brain, secondary to the energy emitted by the cell phones.

Researchers said further studies are needed to determine if these effects from cell phones could have potential long-term health consequences.