“This kind of reduction is unprecedented,” Mrs Roberts said.So far 6,000 families in Leeds have been given the lessons, with 625 children a year “saved” from obesity. The review by Prof Dame Sally Davies will examine which measures could help to meet targets to halve rates of childhood obesity by 2030.Research involving Oxford University found that the eight-week programme In Leeds showing parents how to “take charge” has been linked to a significant drop in obesity levels.The scheme, which costs councils £50 per family, is aimed particularly at deprived areas.Ministers have said efforts to prevent obesity in toddlers will form a central part of a Green Paper this summer. The Government’s former obesity tsar said the results were “astonishing”. Obesity rates among five-year-olds in England remained unchanged between 2013-14 and 2016-17, at around 9.4 per cent.However, rates in Leeds dropped from 9.4 per cent to 8.8 per cent over the same period, according to the study presented at the European Congress on Obesity in Glasgow. The Health Secretary has backed parenting classes to tackle Britain’s obesity epidemic ahead of the launch of a national review.Matt Hancock said he believed in “targeted support” for families, highlighting a scheme in Leeds which has been the first English city to see a fall in the number developing weight problems.The eight week programme aims to show parents how to “take charge” of their children’s diet, and encourage healthy habits.Today Mr Hancock will ask the country’s chief medical officer to review the evidence on which measures work best to combat obesity.Last night he told The Daily Telegraph: “I want targeted support and I want lots more support in schools. Leeds is the only place in the UK where obesity levels are falling. It is targeted interventions at the people who really need support, rather than taking the same approach to everybody,” he said.Mr Hancock – who was last week teased for his own habits when caught on camera eating a waffle – added: “There is some who say we need blanket measures across everybody, but everybody enjoys the odd caramel waffle from time to time. All things in moderation, but we do need targeted support for people who particularly need our help.” Kim Roberts, chief executive of the Health Exercise Nutrition for the Really Young scheme adopted in Leeds, told how parents are encouraged to be “in charge” of their families. She said: “We want parents to be able to hold boundaries, so they are able to say ‘no’ to pester power around snacks.”Leeds was compared with 15 other cities in England – none of which recorded such a turnaround. Want the best of The Telegraph direct to your email and WhatsApp? Sign up to our free twice-daily Front Page newsletter and new audio briefings.