According to the FTC, there is no scientific proof that so-called shields significantly reduce exposure from electromagnetic emissions. Products that block only the earpiece – or another small portion of the phone – are totally ineffective because the entire phone emits electromagnetic waves. Such shields "may interfere with the phone's signal, cause it to draw even more power to communicate with the base station, and possibly emit more radiation."[47] The FTC has enforced false advertising claims against companies that sell such products.[48]
Several studies have investigated the other health effects (other than cancer) of mobile phone usage on human health. Hypotheses connecting mobile phone use to effects such as headaches, fatigue, sleep disorders, memory, vision or hearing impairment, have not been proven in established studies. A connection with reduced fertility has also not been scientifically proven.
Since speaking with Samet, further details came out from a large study that beamed high levels of phone radiation at rats and mice. While there remain quirks in the findings, the latest evidence still doesn’t find a link between phone radiation and cancer. In response, the FDA said, “Taken together, all of this research ... [has] given us the confidence that the current safety limits for cell phone radiation remain acceptable for protecting the public health.”
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2. Our products are designed to provide an anti-radiation barrier between the device and the body. This way, the devices are still usable and able to send and receive signal out of the non-shielded side while shielding the EMF away from the body. Because of this, you will only see a reduction in EMF levels on the shielded side of the device. The test you have conducted shows the highest levels from anywhere around the device.

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.