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.
Radiofrequency radiation is a form of electromagnetic radiation. Electromagnetic radiation can be categorized into two types: ionizing (e.g., x-rays, radon, and cosmic rays) and non-ionizing (e.g., radiofrequency and extremely low frequency, or power frequency). Electromagnetic radiation is defined according to its wavelength and frequency, which is the number of cycles of a wave that pass a reference point per second. Electromagnetic frequencies are described in units called hertz (Hz).