Despite hailing the success of the levy, Oliver criticised wider Government efforts to tackle the issue, which he suggested had been sidetracked by Brexit.
Appearing alongside fellow chef Hugh Fearnley-Whittingstall in front of the House of Commons’ Health and Social Care Committee, Oliver told MPs the childhood obesity strategy published by ministers in August 2016 had been “a massive disappointment”.
“I think we let British kids down, I think we let British parents down,” he said.
However, Oliver expressed hopes of greater measures being included in the next chapter of the strategy, expected this year, as he called for a “multi-pronged approach” across Whitehall departments.
Describing childhood obesity as a “catastrophe” and an “emergency”, Oliver – who has campaigned on the issue for 14 years – said: “The crisis since the millennia has only got worse.”
Fearnley-Whittingstall agreed the problem is “running very wide and very deep”, telling MPs: “Some single headline-grabbing piece of legislation or one or two moves by a couple of big companies isn’t going to do this.”
Making an apparent reference to Prime Minister Theresa May, he added: “Today is 1 May, this is May Day for the obesity crisis and you can read the word May any way you like.”
Despite his lack of enthusiasm for the eventual childhood obesity strategy published within Mrs May’s first weeks in Downing Street, Oliver praised the success of the Soft Drinks Industry Levy announced in March 2016 by ex-chancellor George Osborne.
Having taken effect earlier this month, Oliver described how the levy has led to a “turbo-charged reformulation” of sugar-heavy drinks and has been “one hell of a tax that made a difference straight away”.
He explained how two out of three soft drinks companies have reduced sugar and reformulated their drinks following the introduction of the levy.
And Oliver added the tax should result in around £250m being ploughed into school breakfast clubs and school sports.
Fearnley-Whittingstall praised the levy for breaking the “taboo of mandatory legislation with consequences”, with the publicity generated by its announcement making Britons aware of the “staggering amount of sugar” in drinks.
Both chefs shied away from supporting a tax on food groups beyond sugary drinks, but Oliver suggested widening the levy to milk drinks.
He said: “I definitely don’t think we should overuse taxing without really, really rigorous data and measurement.
“But, I think there is some logic in opening out to milk products.”
Oliver told MPs some of these are “absolutely jam-packed full of additives and sugar” but are currently outside the sugar levy.
He displayed to MPs a bottle of strawberry Yazoo, which he said contains nine teaspoons of sugar, while Fearnley-Whittingstall held up a bottle of Mars milk drink, which he said contains 10 teaspoons of sugar.
Both witnesses also stressed to the committee the need to install a better system of food packaging, which Oliver suggested could be a benefit of the UK leaving the EU.
He told MPs how “one of the upsides of Brexit will be more controls over honesty, packaging and colour coding”, with the EU currently responsible for packaging legislation.
Sky News has contacted both Mars and the manufacturers of Yazoo for comment.