Wikipedia
PEERtrainer
PEERtrainer is a social networking website that aims to help people lose weight. It is based on the idea that social support is the most important factor in weight loss. Development on the website began in August 2004; it was launched in October 2005. The potential of the company's health oriented social networking platform has generated interest from leading healthcare firms. PEERtrainer's says its membership has reached more than 900,000 since its launch in 2005.