Your own body produces electricity electrochemically. This energy generation produces a natural electromagnetic field measured at 7.8 Hz. Electromagnetic fields that are artificially produced by routers, cell phones and other WiFi enabled equipment interfere with our body's own field. Some people are so sensitive that they become physically ill or experience headaches and nosebleeds. Long term use can cause health issues including infertility if the body is excessively bombarded and not properly shielded.