Jamie Oliver has called on the prime minister "to do the right thing" to tackle childhood obesity.
Oliver and fellow celebrity chef Hugh Fearnley-Whittingstall are due to give evidence to the Health and Social Care Select Committee later to offer their advice on how to tackle the problem.
"A lot of stuff that will change the goalposts is industrial, behind the scenes, reformulation," he said.
He told the BBC that as tasting food is his job, he runs the"daily mile".
"When you hit a certain age - 40 - you have to try a little bit harder and certainly for my kids, [I'm] trying to get them to do some sporty stuff," he added.
Oliver has campaigned for healthy eating for children and teenagers for years and said he has cross-party support for more to be done.
Hugh Fearnley-Whittingstall is currently presenting the BBC One series Britain's Fat Fight in which he looks at why Britain is the most obese country in Western Europe and what can be done about it.
Jamie Oliver said: "Over the last 18 months, we've got all the opposition parties to agree to a manifesto that is a multi-pronged attack to protect child health and we've got politics out of the way.
"I think everyone can do their bit. In Amsterdam, they have had a lowering of childhood obesity by 12% in three years and that was a multi-pronged strategy.
"They stopped the sponsorship of junk food advertising on sports events. We had an opportunity in the Olympics, the biggest stage on the planet, to say something positive and of course it was sponsored by two junk food advertisers.
"We know there are current standards that protect children from junk food until 18:00 but we think they should stretch it until 21:00. We know that where the masses of kids are in those primetime slots - if you watch a season of that, then that's literally a film of junk food advertising."
Oliver also called on supermarkets to do more to help improve the health of the nation.
"This is about making real food cheaper," he said. "You can get into a rhetoric where you are taking something away, making it more expensive.
"'Bogofs [buy one, get one free] or multi-buys make you buy more, spend more, eat more and waste more and that's a fact. We love the idea of discounting foods, making it cheaper but we would love it and we think it's fair and democratic if it was at least equal to make fresh food and real food accessible.
"There no structure (to the offers) at the moment so what happens is that everyone says they do some fresh food, but if you look at the stats, it's highly rated towards products that are really high in salt, fat and sugar.
"We think fairness is choice, whether that is a vending machine, a petrol station or even a restaurant."