In a world where conspiracy theories have never been so popular, it's difficult to know who to believe. Should we be more afraid of fluoride in our drinking water, or invisible chemical trails in the air we breathe? Are world affairs decided by democratically elected politicians, or by shadowy groups of powerful individuals with private agendas? Balancing what the theorists say with the official line, here is all the evidence you need to decide for yourself exactly how paranoid you should be.