Cellphones stimulate our cells, but is that a bad thing?

A study published Tuesday in the Journal of the American Medical Assn. found evidence that cellphones’ electromagnetic energy prompts unusual levels of activity in a user’s brain, raising concern that our national habit of jabbering into our 300 million cellphones might not be completely innocuous.

But wait. Haven’t we been told that stimulating our brains with intellectual challenges, new experiences and copious social interaction is good for us? Why the ominous tone?

The fact is, the JAMA findings could lead researchers in many directions, not all of them scary. But there do seem to be some reasons to see the potential for health risks in those findings.

Michael Hansen, staff scientist for the watchdog group Consumers Union, notes for starters that the study’s findings clearly undermine reassurances issued by the Food and Drug Administration in response to public concerns arising from early studies (which were later contradicted by other studies) linking cellphone use to brain cancer.

The FDA’s website on the subject states that there is no reason to believe the radio-frequency wave or the electromagnetic energy given off by cellphones can cause harmful changes in human tissue. The electromagnetic energy is not sufficiently powerful (as, say, are X-ray or gamma ray energy) to cause changes in human cells. And the radiofrequency emitted periodically by cellphones in standby mode can cause the device to heat up, but not enough to harm human tissue with which it comes in contact, the FDA says.

Hansen says that by showing that electromagnetic energy causes brain cells to behave in ways they would ordinarily not, the JAMA study demonstrates that it can also lead, perhaps over the long term, to changes in those cells. The JAMA study goes on to suggest it is the placement of the antenna that affects which cells of the body are activated by electromagnetic energy; that finding, says Hansen, could mean that cellphones are activating (and possibly changing) cells in different parts of our bodies, depending on how we use those phones.

So, the person who keeps his cellphone on his belt and uses an earpiece may be activating cells in his viscera. The teenager who lays the phone in speaker mode on her chest may be prompting changes in the activity of cells in her breasts or at her thyroid.

Hansen cites a paper published last year that found that cellphone use increased the rate of saliva production in the parotid glands (the ones closest to the cheek) of subjects. Put that finding together with a pair of Israeli studies suggesting a link between heavy Israeli cellphone use and a rise in parotid gland tumors in that country, and Hansen says, you should have concerns.

But Dr. Nora Volkow, the JAMA study’s lead author, suggested a far less ominous take on the JAMA findings. That cellphones’ electromagnetic energy stimulates activity in nearby brain cells may one day suggest therapeutic uses for electromagnetic energy, she said in an interview. After all, transcranial magnetic stimulation, which temporarily suppresses or “jams” activity in brain cells nearby, is widely used in neuroscience research, and is being studied in the treatment of depression, epilepsy and even in halting eyelid spasms. Deep-brain stimulation is considered a promising treatment for some stubborn forms of depression.

That said, Volkow indicated she’s taking no chances. A frequent cellphone user, Volkow says she uses her wireless device in speakerphone mode, or puts in an earpiece and keeps her wireless device away from her head.

“I don’t want my brain to be unnecessarily activated,” said Volkow. But recalling that a stimulated brain is a good thing, she shifted course a bit, adding, “I want it stimulated by thoughts and ideas, not by electromagnetic energy.”