Obesity is predicted to continue rising
Soaring obesity levels look set to drain local health and public service budgets, which will mean higher taxes for all, experts warn.
Obesity could cost NHS in England £6.3bn by 2015 if no effective action is taken says the Department of Health.
Local councils in England and Wales are already shelling out tens of thousands of pounds on "fat-friendly" services, like widening crematoria furnaces.
This comes as work shows obesity levels may have been grossly underestimated.
The Local Government Association, which represents over 400 councils in England and Wales, says that Britain is fast becoming the "obesity capital of the world" and even more must be done to stop the nation's waistline continuing to expand.
Cllr David Rogers, LGA spokesperson on public health, said: "It's a massive issue for public health but it also risks placing an unprecedented amount of pressure on council services.
"Obesity is increasingly costing the council taxpayer dear. It falls to social services to care for the house-bound obese adults, to invest money in encouraging people to be active and to replace school furniture that is just too small for larger pupils.
"Council equipment and infrastructure is having to be modified to deal with a population that is getting larger and larger."
IMPACTS ON SERVICES
Furniture in school classes, gyms and canteens is being made wider for larger children
Town halls are widening crematoria furnaces
Ambulances are being re-equipped with extra-wide stretchers
Councils are having to provide obese residents with help towards walking aids and adaptations to their houses
Councils are stepping in to deal with cases where the welfare of dangerously overweight children is put at risk
Fire services being called in to winch obese members of the public out of dangerous buildings in emergencies
Social services is running up costs of caring for house-bound people suffering from obesity-related illnesses
He said social services were increasingly having to consider taking action in cases where parents consistently placed their children at risk of morbid obesity through bad diet and lack of exercise.
He called for a national debate about the extent to which it is acceptable.
Tam Fry of the National Obesity Forum said "draconian" interventions were necessary. He warned that, as a nation, we are all getting fatter and risked early death as a result.
Chief Medical Officer Sir Liam Donaldson said: "Nothing has changed in my mind about the seriousness of this threat to the country's future health.
"In England almost two-thirds of adults and a third of children are either overweight or obese.
"Without action this could rise to nine in 10 adults and two-thirds of children by 2050."
A US doctor says Britain's health calculations are wrong and that three out of four adults in this country are now overweight or obese, not two-thirds.
Dr Francisco Lopez-Jimenez of the Mayo Clinic told the National Obesity Forum in London many people with a normal body mass index or BMI - the figure typically used to determine obesity - still weigh too much because this measure does not distinguish between fat and muscle, which weighs more.
His study of more than 2,000 men and women with a normal BMI found one in five still had excess body fat, which Dr Lopez-Jimenez says is a true marker of obesity.