File photo dated 19/10/15 of Jamie Oliver who has said he does not want to be a &quot;Nazi&quot; about sugar after admitting he buys his children a bag of sweets once a week. PRESS ASSOCIATION Photo. Issue date: Sunday November 1, 2015. Oliver, whose latest campaign is calling for a tax on sugar products, urged David Cameron to be &quot;bold and brave&quot; last month after the Prime Minister vetoed introducing a levy. See PA story HEALTH Oliver. Photo credit should read: Dominic Lipinski/PA Wire