For now, it’s probably better not to spend too much of your time worrying: you’re surrounded by cellphone signals, Wi-Fi signals, and all other kinds of radio frequency radiation day in and out — not just when you put your phone up to your face. And until the evidence suggests otherwise, all of this is still considered less of a cancer risk than eating red meat (which you shouldn't freak out about that much either).
There are alternate technologies that can be considered when looking to reduce cell phone radiation exposure which we don’t use. Why don’t we use them? Incorporating technologies such as antennas into a case can greatly reduce outgoing cell phone radiation levels when close to the cell tower, but not totally. If farther away, the cell phone signal levels increase, as does the radiation exposure to the body, possibly to unacceptable output power levels. This design does not reduce radiation exposure from the WiFi and Bluetooth RF because cell phones do not have the capacity to reduce their power levels whether or not an antenna is present. Maybe just as important, this design does not have the shielding capacity for ELF emissions which have the same dangers as the RF emissions. Other device attachments like buttons and stickers are minimally effective to totally ineffective, with no scientific basis. In short, there are no other technologies capable of up to eliminating all of the many potentially harmful cell phone emissions from hitting the body.
When we think of harmful radiation, things like X-rays or gamma rays usually come to mind, but these types of radiation are different from mobile phone radiation in important ways. Radiation on the ultraviolet side of visible light, like those types just mentioned, has a wavelength that is short enough to alter some of the chemical properties of the objects it interacts with. It is referred to as ionizing radiation, for this reason. Non-ionizing radiation, which includes visible light, microwaves and radio waves, is typically regarded as harmless. Large amounts of it can produce a heating effect, like in a microwave oven, but no short-term damage has been linked to exposure to non-ionizing radiation.
Your phone sends radiofrequency, or RF, waves from its antenna to nearby cell towers, and receives RF waves to its antenna from cell towers when you make a call or text or use data. The frequency of a cell phone’s RF waves falls between those emitted by FM radios and those from microwave ovens, all of which are considered “non-ionizing” forms of radiation. That means that—unlike radiation from a nuclear explosion, a CT scan, or a standard X-ray—the radiation from your phone does not carry enough energy to directly break or alter your DNA, which is one way that cancer can occur. (FM radios and microwaves don’t raise alarms, in part because they aren’t held close to your head when in use and because microwave ovens have shielding that offers protection.)
Regular battery-powered watches (and all other battery-powered tech, for that matter) also produce some level of EMFs, but that level is far lower than the amount emitted by tech devices that are plugged in, or that receive and transmit information wirelessly. The same rule applies however; if you can turn it off and keep it away from your body, then do so whenever possible.
Laptop computers are best placed on a table at as much of an arm’s length away as possible to minimize radioactive contact. If you must use your laptop on your lap, you can purchase a laptop cooling pad which will add a bit of extra space between the device and your body. Even better are laptop cases specifically designed to shield against radiation.
With the background levels of information-carrying radio waves dramatically increasing because of the widespread use of cell phones,Wi-Fi, and other wireless communication, the effects from the near and far-fields are very similar. Overall, says Dr. Carlo, almost all of the acute and chronic symptoms seen in electrosensitive patients can be explained in some part by disrupted intercellular communication. These symptoms of electrosensitivity include inability to sleep, general malaise, and headaches. Could this explain the increase in recent years of conditions such as attention-deficit hyperactivity disorder (ADHD), autism, and anxiety disorder?
The only consistently recognized biological effect of radiofrequency radiation in humans is heating. The ability of microwave ovens to heat food is one example of this effect of radiofrequency radiation. Radiofrequency exposure from cell phone use does cause heating to the area of the body where a cell phone or other device is held (e.g., the ear and head). However, it is not sufficient to measurably increase body temperature. There are no other clearly established effects on the human body from radiofrequency radiation.