Jamie Oliver has called on politicians to get serious about fighting childhood obesity, claiming that “positive social change” on the issue can be achieved.

An estimated 200 million children are now overweight globally and at risk of bullying, depression and longer-term damage to their health, including diabetes and heart disease.

The chef, who is teaming up with TES to broadcast a live cooking lesson to thousands of schools next month, said that the world obesity epidemic was preventable, but needed a “visionary” politician willing to tackle it.

With a general election due next year, Mr Oliver said: “Let’s see if we have one pioneer, one visionary who’s going to put prevention [of childhood obesity] at the heart of their campaign. Let’s see how many of them [the political parties] start really talking about children’s health and public health.”

Mr Oliver said that tackling obesity was possible if action was taken on many fronts - not only in schools, but in homes, workplaces, supermarkets and food outlets.

“You can’t have one arm of the government investing money in food education and school lunches and then have another part allowing junk food, en masse, to be licensed and given permission to trade within a stone’s throw of a school on every corner,” he said.

As part of Food Revolution Day, on Friday 16 May, Mr Oliver will be broadcasting a cooking class to children across the globe, streamed via the combined channels of TES in the UK, TES Connect in the USA and Australia and his own Food Tube channel.

He hopes to break the Guinness World Records attempt for the most people cooking the same dish, a “Rainbow Salad Wrap”, on the same day.

The high-profile chef’s campaign to improve school food began with the 2005 programme Jamie’s School Dinners. 

In an interview with TES, Mr Oliver added: “There is not one country on the planet that has smashed it [the obesity crisis]. Not one country where obesity levels are coming down.

“I think positive social change is not that far away and I think it’s not that hard, but what needs to be done is for about 50 or 60 separate decisions and initiatives to happen at once, all followed by a five-year strategy. 

“The only thing that will make a change is lots of changes.  Governments ask ‘what is the one thing we can do?’  But if you think [just] one thing, you’re always going to lose; nothing will be achieved.”

Latest figures for England show that almost a third of 10- and 11-year-olds and over a fifth of 4- and 5-year-olds were overweight or obese. 

Register your class or school to join in with the live cooking lesson on Food Revolution Day.