Today is World Obesity Day, the annual campaign to reverse the global obesity crisis by helping people to achieve and maintain a healthy weight. So... what’s the best way to do that?

It's a simple question to ask, but a controversial one to answer. Last month saw a public row over the efficacy of so-called 'fat shaming', after US late-night TV host Bill Maher called for it to "make a comeback". His remarks, that "shame is the first step in reform", led to a rebuttal from fellow host James Corden, who dedicated a segment of his show to demonstrating the result of fat shaming. "It makes people feel ashamed, and shame leads to depression, anxiety and self-destructive behavior," said Corden. "Self-destructive behaviour like over-eating.”

So fat shaming probably doesn't work – but what about public initiatives such as the sugar tax? Yesterday, chief medical officer Dame Sally Davies made headlines with the recommendation that people should be banned from eating on public transport in the UK to combat our obesity crisis (which costs every taxpayer more than £400 a year). Again, the suggestion is contentious: restrictive government measures on food are seen as symptomatic of what Prime Minister Boris Johnson describes as “the continuing creep of nanny statism.”