Figures from the government reveal that almost one in 10 children in the UK is obese.
The Department of Health statistics are part of an examination of the nation's health prepared in a bid to help people live longer and happier lives.
It is the first time figures, which show a "health gap" between the affluent and the poor, have been broken down by each local health authority.
They showed obesity among reception year children averaged just under 10% - with Teesdale in County Durham having the lowest rate (5%) and Hackney in London the highest (16%).
Government figures released in February showed nearly a quarter of children aged four to five (22.9%) and almost a third of 10 to 11-year-olds (31.6%) were obese or overweight.
But the true figure could be much higher - as parents can elect to "opt out" of having their children weighed at school.
The Health Profiles, published online, were prepared for every local authority and region across England by the Department of Health and the Association of Public Health Observatories.
Health minister Dawn Primarolo said: "Inequalities around the country are stark, but the NHS and local authorities can use these profiles to target local health hotspots with effective measures to make a real difference."