Americans are getting fatter at a rate never seen before, a report shows.
About two-thirds of US adults are obese or overweight
In the past year, the adult obesity rate rose in 48 of America's states, and nationally from 23.7% to 24.5%, Trust for America's Health found.
In 10 states, over a quarter of adults are now obese, despite campaigns alerting people to the dangers of over-eating.
Mississippi, famous for its calorific mud pie, ranked the highest, followed by Alabama and West Virginia.
The non-profit organisation said the situation had reached crisis point and current policies were failing.
Currently, about 119 million, or 64.5%, of US adults are either overweight or obese.
According to projections, 73% of US adults could be overweight or obese by 2008, Trust for America's Health warned.
In turn, this would mean many more people with obesity-related illnesses such as diabetes and heart disease, which could cost the nation billions of dollars.
The biggest rises in obesity have been seen in the south-eastern states. Oregon in the north-west was the only one not to see an increase between 2003 and 2004, maintaining a steady adult obesity rate of 21%.
Hawaii was not included in the data analysed from the Centers for Disease Control and Prevention.
The US Department of Health and Human Services set a national goal of reducing obesity in adults to 15% or less of the population by 2010.
Trust for America's Health believes this target will be missed.
Executive director Shelley Hearne said: "We have reached a state of policy paralysis in regards to obesity.
"We need more and better data so we can make decisions to get out of the debate limbo in which we are stuck.
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"We have a crisis of poor nutrition and physical inactivity in the US and it's time we dealt with it."
The trust says more needs to be done to tackle inactivity and poor diet, focusing particularly on schools to prevent bad lifestyle habits being learned in childhood.
It warned: "There will be no quick fixes. A sustained effort will be required to reverse the current trend."
Dr Ian Campbell, chairman of the National Obesity Forum in the UK, warned that the same was happening in other Western countries.
"We have seen this year-on-year rise in obesity in the US that has been mirrored in the UK. We know we are only about seven years behind them.
PERCENTAGE OF OBESE ADULTS PER STATE IN 2004
Rank 1 - Mississippi - 29.5%
Rank 2 - Alabama - 28.9%
Rank 3 - West Virginia - 27.6%
Rank 50 - Colorado - 16.4%
Source: The US Centers for Disease Control and Prevention
"When will we in this country wake up and smell the coffee?
"The Americans have woken up to it before and clearly they are still in a state of policy paralysis.
"In this country, the government is working very hard to try and develop a strategy for obesity but at the moment very little practically is being done.
"It really is time that we got our finger out and started making real changes.
"This is no cosmetic irritation, it is a serious medical problem."