Any electromagnetic wave can be considered as a kind of raw energy, so it is not surprising that it can be dangerous to our bodies if it is strong enough. Even visible light may harm us if it is strong enough, and lasts long enough.
But different kinds of EMF have different qualities. Some frequencies lack penetrating power and will actually bounce off the skin, so any immediate damage is to the skin alone. But other frequencies of EMF penetrate the body in various degrees, both at the low and high ends of the electromagnetic spectrum. Those which penetrate deeply can do damage deep within the body.
EMF Intensity. Exposure to strong EMFs may cause damage, even though the exposure is of short duration.
In one study, researchers asked pregnant volunteers to wear a device which measured the highest intensity (peak) EMF in a 24 hour period. Results indicated that higher peak EMFs correlated with higher rates of damage (in this case, miscarriage).
Cumulative EMF Exposure. During a normal day a person will be exposed to EMFs of various frequencies. For example, these could arise from electric shavers and hairdryers, car, bus or train travel, domestic appliances such as heaters, ovens and microwaves, neon lights, computers, household wiring, power lines, cell phone carrying and use, to name just a few of the more common sources. The combination of these exposures may overwhelm the body defences and repair mechanisms.
EMF Transience. It could be more stressful biologically to be exposed to a fluctuating EMF which arises from a source which cycles on and off (for example a photocopier, printer or refrigerator) than from a similar appliance that remains steadily on all day.
EMF Frequency. It is not yet known with certainty which electromagnetic frequencies cause which health effects, but it does appear that different frequencies affect us in different ways. The higher frequencies contain more energy, so it is not surprising that waves like X-Rays and Gamma Rays which are at the high-frequency end of the spectrum appear to do the most damage. But extremely low-frequency EMFs have proven health risks too.
Superimposed Signals. An electromagnetic wave can be modulated in various ways to carry a signal, which might be digital or analogue. Where the wave is used for communication (e.g. radio, television, mobile telephony etc) it is normal to have a signal imposed on a carrier frequency. There is evidence that, in some cases, the signal component can be more harmful than the carrier wave EMF itself, probably because it is pulsing. That is one reason why cell phone and cell tower EMF could be more damaging than other kinds.
The danger to our health posed by current levels of man-made electromagnetic fields, is real. This is the consensus of a growing number of responsible scientists and professional healthcare workers.
Fortunately there are many ways to protect ourselves and our loved ones, before our health is affected. See our page EMF Protection.