Low-level radiation is one type of EMF exposure and is emitted from cell phones, Wi-Fi routers, Bluetooth devices, computers, and even power lines. Some scientists report that this type of EMF exposure can cause sleep disturbances, including insomnia; headache; depression and depressive symptoms; changes in memory; and lack of concentration. You can reduce the risk by using the speakerphone function on your cell phone instead of holding it to your ear. Charge your phone in a different room at night, or put it on airplane/flight mode while you sleep. Products are also available that counteract harmful frequencies using healthy ones.