The “nudge” or, more formally, libertarian paternalist agenda has captured the imagination of at least some of the British policy elite, epitomised by the creation of the Cabinet Office’s behavioural insights team (the so called nudge unit).1 The reason for the political popularity of nudging is obvious: it offers politicians a tool by which they can offer guidance, without enforcement, on individual behaviour change that is good for and, on reflection, preferred by, individuals themselves. Various nudge policies have been proposed to tackle obesity, but before considering these, I will try to clear up a few misconceptions about what libertarian paternalism conceptually entails.