Leeds has become the first city in the UK to report a drop in childhood obesity after introducing a programme to help parents set boundaries for their children and say no to sweets and junk food.

Only a few cities in the world, notably Amsterdam, have managed to cut child obesity. Like Amsterdam, the decline in Leeds is most marked among families living in the most deprived areas, where the problem is worst and hardest to tackle.

“The improvement in the most deprived children in Leeds is startling,” said Susan Jebb, a professor of diet and population health at Oxford University, whose team has analysed the city’s data. Over four years, obesity has dropped from 11.5% to 10.5% and the trajectory is steadily downwards. Among the more affluent families, there was also a decline from 6.8% to 6%. Overall the drop was from 9.4% to 8.8%.

The data comes from the national child measurement programme (NCMP), which requires all children to be weighed at the start and end of primary school. The biggest decline in obesity in Leeds is 6.4% in the reception class, at about the age of four. From 2016 to 2017, 625 fewer reception class children were obese.

No such data has been reported elsewhere in the UK, where childhood obesity is a major concern. Almost a third (28%) of all children aged two to 15 in England are overweight or obese. The measurement programme shares the progress made in each city with those considered comparable. For Leeds, the 15 closest “neighbours” at the start of the study period in 2009 were Sheffield, Kirklees, Bristol, Newcastle upon Tyne, Coventry, Bolton, Wakefield, Derby, Bradford, Dudley, Medway, Liverpool, Swindon, County Durham and Warrington. The obesity rates there and across the country have not shifted.

“For England it’s absolutely flat,” said Jebb, who added that the dropping rate in Leeds appeared to be a trend. “This is four years, not one rogue data point,” she said at the European Congress on Obesity in Glasgow where she presented the research, also published in the journal Paediatric Obesity.

“Everybody is going around saying Amsterdam is doing something amazing. Well, actually, Leeds is too.”

Jebb, a former government adviser, says they cannot be sure what has turned the tide in Leeds – but it could involve a programme called Henry that the city introduced as the core of its obesity strategy in 2009, focusing particularly on the youngest children and poorest families. Henry (Health, Exercise, Nutrition for the Really Young) supports parents in setting boundaries for their children and taking a firm stance on issues from healthy eating to bedtimes.

Quick guide What is Henry? Show Hide Henry (Health, Exercise, Nutrition for the Really Young) aims to help families live healthy, active and more harmonious lives. Out go the threats of no pudding and the bribes of ice cream and sweets. Instead, parents and carers are given confidence to be fair but firm, offering choice but only between oranges and apples, or carrots and peas. Parents are asked to decide what changes they want to make to their lives and set goals in the first week of the eight-week course. The agenda for week 2 is how to juggle life with young children so everyone gets what they need. In week 3, parents are given ideas for responding to children’s needs without giving in to all their demands. Then in week 4 there is advice on managing mealtimes to keep the whole family happy and reduce stress. “I thought it would feel like school but it doesn’t,” said one parent during an evaluation of the programme. “No one tells you what to do, you learn for yourself and from the others in the group. Henry is a real eye opener – it’s turned our life round and we are much healthier now. My son is an only child so I’ve realised I need to eat with him and eat healthier foods – who else is he going to copy?” Doing things together – whether eating or playing in the park – is key. Routines for bedtime and meals at a table, not in front of the TV, are encouraged. So are non-food rewards. Henry parents might allow the child to add a brick to a tower that the family is building over several days as a way of encouraging cooperation, rather then offering biscuits when a child has done something well.

Henry’s chief executive, Kim Roberts, said the drop in obesity in Leeds was “unprecedented … The indicators are that this isn’t happening in other cities.”

The programme encourages authoritative rather than authoritarian parenting, she said.

“Authoritarian parenting is when children are told what to eat and what to do, such as being banned from leaving the table until they have eaten their sprouts,” said Roberts. “Permissive parenting is asking children what they want to do.

“But Henry encourages a third approach known as authoritative parenting, where parents make it clear they are in charge, but also respond to their children.”

Instead of being asked what vegetable they want with dinner, children might be asked whether they would like carrots or broccoli. Instead of being told to go to bed, they are asked where they want to read their bedtime story.

Instead of telling a child to stop watching television, a parent could ask whether they would like to turn the television off or whether the parent should do it.

Lisa, who joined a Henry parenting course when her oldest daughter was two, is enthusiastic about her family’s experience of the programme. Her children now eat sweet potato and beetroot. She learned a lot about healthy eating, saved money by planning meals and lost two stone herself.

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“I think it made me a better parent because of all the parenting skills stuff. I was able to share some of the ideas with my partner and as a result the kids became calmer and happier, which helped us feel less stressed too,” she said.

Kayleigh constantly argued with her daughter, who had just started school and was overweight. “Lexi had a very limited diet and whenever I tried to get her to try anything new she would reject it, so I stuck to what I knew she would eat,” she said. The programme inspired her to take Lexi to the park to chase the dog. She turned the television off at mealtimes and introduced healthy food choices.

“My confidence as a parent was increasing as the weeks went by. I became more conscious about responding to Lexi’s needs while still remaining in charge, like understanding that she would act up sometimes because she needed some attention and balancing that with what I needed to do,” she said.

Janice Burberry, the head of public health at Leeds city council, said the early years were a good time to intervene to support families. “Parents want to do the best for their children. During pregnancy they are more receptive to change, they want to give their children the best start,” she said.

“We wanted to focus on prevention because it’s very, very difficult when obesity has taken hold to tackle it.

“We understand that there is no magic bullet here. Parents are experts in their own lives and they know what they can and can’t achieve. The strategy of Henry is about sitting alongside parents and thinking through what’s right for them.”

The public health minister, Seema Kennedy, was enthusiastic. “There are some fantastic pockets of work happening in early years already, and while still in the early phases, it is encouraging to see what can be achieved locally through interventions like this,” she said. “I know how hard it can be for busy parents to make healthy choices for their families, so anything that can make it easier is a real lifeline.”

• This article was amended on 2 May 2019 to use a different chart type in order to add clarity to the presentation of data.

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