Here's where the confusion starts.
Some scientific studies show a possible link while others show no link. Meanwhile, there are plenty of people taking to the Internet with horror stories of tumors appearing where they regularly keep their phones next to their body.
The study defines "heavy cellphone use" as 15 hours or more every month for more than five years. At that level, the risk of glioma and meningioma tumors increased two to three times.
Oddly, unlike any previous study, this one showed the tumors appearing on the opposite side of the head from where participants typically held the phone.
Still, as always, this study isn't conclusive, and it found no cancer risk with moderate and light cellphone use. So, where does that leave us?
For myself and my family, I assume the worst - that prolonged exposure does increase cancer risk - and take steps to stay safe. The preventative measures aren't expensive or inconvenient, so why not?
I'll tell you those steps in a moment. Before that, it's a good idea to know why this issue is so hard to settle.
It comes down to radiation. For this general discussion, there are two main types of radiation: ionizing radiation and non-ionizing radiation.
Ionizing radiation includes gamma rays, X-rays and some ultraviolet rays. These are known to damage your DNA, increasing the risk of cancer. When you get sunburned, that's thanks to ionizing ultraviolet radiation.
Non-ionizing radiation includes visible light and radio waves. Radio waves include microwaves, which is what cellphones and wireless routers use. Non-ionizing radiation doesn't damage your DNA or cells. That's a good thing, too, given how much exposure we have to things like visible light.
In extreme quantities, non-ionizing radiation can burn you - a high-intensity laser and a microwave oven are good examples. However, you don't get the same kind of damage as sunburn.
Back to the topic, cellphones don't even put out enough radiation to burn you. The FCC regulates cellphone radiation and keeps it well below dangerous levels. A measurement of what your phone puts out is the Specific Absorption Rate, or SAR, figure in your phone's manual.
So, on paper, cellphones should have no effect on humans. Still, there is an effect.
One study, for example, shows that when held near the skin, a cellphone signal causes glucose in the area to metabolize faster after 50 minutes. Scientists are still trying to sort out what long-term consequences this could have.
There's also the question of whether long term exposure might accumulate into negative side effects. And many critics point out that the government bases its safety figures on adults, not children who might be more at risk.
With so many things that can contribute to cancer - genetics, food additives, gasoline fumes, the sun, most chemicals and much more - trying to figure out what part cellphone radiation plays is very tricky.
But, as I said earlier, why take the risk? Here are some things I do to minimize exposure to cellphone radiation for myself and my family.
When you're making calls, switch your phone over to speaker mode. This keeps it away from your head and major organs. Manufacturers recommend keeping the phone 0.8 inches or farther away from your skin while on a call. Even that little distance will seriously drop the radiation your body might absorb.
During phone calls, your phone is outputting the strongest signal. It also uses a stronger signal when you're moving or in a low-signal area. So, make calls when you're stationary or have a good connection.
Send texts instead of making phone calls. While you're texting, the cellular signal is much weaker.
Men: Keep the phone out of your pockets. Women: Don't put the phone in your bra. If you have to keep it close to you, switch to airplane mode, which disables the cellular and Wi-Fi signals.
For frequent talking, consider a Bluetooth headset. Yes, it also puts out radiation, but at a thousandth of the amount of a cellphone. Just remember to take it out of your ear between calls.
A wired headset is an option as well. I've seen articles online saying that a headset wire can act as an antenna and actually increase your radiation exposure. However, that information usually appears in ads for radiation-proof headsets, and I haven't seen any actual scientific research to back it up.
On the Kim Komando Show, the nation's largest weekend radio talk show, Kim takes calls and dispenses advice on today's digital lifestyle, from smartphones and tablets to online privacy and data hacks. For her daily tips, newsletters and more, visitwww.komando.com. E-mail her at techcomments@usatoday.com.
