Social happiness could prove to be a contagious idea

DO YOU remember "socially contagious obesity"? It is the idea that one reason people are fat is because they know other fat people. It sounds made up, but the notion is based on solid research by Harvard professor Nicholas Christakis and his colleague James Fowler. Their 2007 study of more than 12,000 people found that having an obese friend increases one's own risk of obesity by up to 57 per cent.