A far-reaching national strategy is needed to tackle the "terrifying health consequences" of the UK's obesity timebomb, leading doctors said today.
A joint report by the Royal College of Physicians, the Faculty of Public Health and the Royal College of Paediatrics and Child Health warned that if current trends continued at least a third of adults would be obese by 2020.
More than half of the UK is either overweight or obese - in 2002 70pc of men and 63pc of women were classed as overweight or obese. A fifth of adults are obese.
The experts warned that action was needed at every level to reduce the number of overweight and obese adults and prevent children from going down the same route.
Their 50-page report - Storing Up Problems: The medical case for a slimmer nation - makes a raft of recommendations to the Government, the food industry, local authorities, the NHS and individuals to tackle the obesity epidemic.
Children are increasingly showing signs of becoming the worst generation yet when it comes to controlling their weight.
The report said that obesity among children aged two to four almost doubled between 1989 and 1998, from 5pc to 9pc.
Among those aged six to 15, rates of obesity trebled from 5pc in 1990 to 16pc in 2001.
The report warned that conservative estimates showed that if these trends continued one-third of adults - a fifth of boys and a third of girls - would be obese by 2020.
Obesity is said to be responsible for at least 30,000 deaths a year in the UK, causing problems such as heart disease, strokes and diabetes.
Professor Peter Kopelman, chairman of the working party which put together the report, said: "This report highlights the terrifying health consequences of the obesity epidemic that will particularly impact on our children unless effective and coherent preventive measures are taken."
The report recommends that a cross-governmental taskforce should be set up at Cabinet level to develop nationwide strategies to tackle the country's weight problems.
They also said that the Government should mount a sustained public education campaign to improve understanding of the benefits of healthy eating and an active life.
Health Secretary John Reid welcomed the report as "a valuable contribution" to the consultation on public health.
"The authors are right to highlight the problem of increasing obesity, particularly among our young people.
"They are also right to point out that this is not simply a matter for the Government, but for everyone who wants to ensure people live the long and healthy lives they deserve."
Celebrity dieter Ann Widdecombe today brought her no-nonsense approach to the issue of obesity, calling for a "sense of proportion".
Former shadow home secretary Miss Widdecombe, who lost 36 pounds on TV show Celebrity Fit Club, said: "I think what we need is proportionality."
The Tory MP added: "We are all being encouraged to watch every last pound and people who look perfectly normal and who are obviously healthy worry themselves into a passion because they put on half a stone over Christmas."
Miss Widdecombe said diet is a matter of common sense.