Experts predict more than 50% of the UK population will be obese by 2050
Copeland in West Cumbria is the fattest local authority area in England, according to new government figures.
The borough has 75.9% of its population classed as overweight or obese, the Public Health England data show.
Overall, 63.8% of adults in England have a body mass index (BMI) of 25 or over - a figure of between 18.5 and 24.9 is deemed healthy for an adult.
The fattest region is the North East, where 68% of people are overweight, followed by the West Midlands at 65.7%.
Other obesity hotspots include Doncaster (74.4%), East Lindsey in Lincolnshire (73.8%) and Ryedale in North Yorkshire (73.7%).
The thinnest local authority areas include several in London, such as Kensington and Chelsea (45.9%) and Richmond upon Thames (47.6%).
Tam Fry, of the National Obesity Forum (NOF), said: "The publication of these figures has to be welcomed because they will give local authorities a better chance of fighting obesity than did 15 years of tackling the epidemic from Westminster.
"County and town halls were handed the poisoned chalice of doing something about the epidemic only last April but were underfunded for the task."
Dr Jane Rossini, Cumbria & Lancashire centre director at Public Health England (PHA), said: "Even in the areas with lowest prevalence of people who are overweight and obese, levels are still high.
"Overweight and obesity are complex issues and influenced by a variety of factors, including social and economic deprivation and age.
"The variation in levels of overweight and obesity across the area, and England as a whole, highlights the extent of the challenge faced by many local authorities."
'Catalyst for action'
Last month, the NOF said estimates that half the UK population would be obese by 2050 "underestimated" the problem and called for GPs to proactively discuss weight management with patients, and routinely measure children's height and weight and adults' waist size.
Joseph Clift, of the British Heart Foundation, said: "These new figures hold a mirror in front of the country's waistline and it reflects a very unhealthy picture.
"The Westminster government need to introduce consistent regulation for advertising unhealthy products on TV and online to stop food companies exploiting loopholes.
"Local authorities need to be designing towns and cities in ways which encourage people to be more active, whether that's by walking or cycling."
Prof Kevin Fenton, director of health and wellbeing at PHA, added: "Many local authorities are already working hard to reduce obesity levels and these new data will help all local areas monitor their progress in tackling these long-standing problems.
"There is no silver bullet to reducing obesity; it is a complex issue that requires action at individual, family, local and national levels."
The figures are based on adjusted, self-reported height and weight measurements collected via questions in the Active People Survey by Sport England since January 2012.