Bloated, blue-collar Americans - gorged on diets of fries and burgers, but denied their share of US riches - are bringing the nation's steady rise in life expectancy to a grinding halt.
Twenty years ago, the US, the richest nation on the planet, led the world's longevity league. Today, American women rank only 19th, while males can manage only 28th place, alongside men from Brunei.
These startling figures are blamed by researchers on two key factors: obesity, and inequality of health care. A man born in a poor area of Washington can have a life expectancy that is 40 years less than a woman in a prosperous neighborhood only a few blocks away, for example.
'A look at the Americans' health reveals astonishing inequalities in our society,' state Professor Lawrence Jacobs of Minnesota University and Professor James Morone, of Brown University, Rhode Island, in the journal American Prospect .
Their paper is one of a recent swathe of studies that have uncovered a shocking truth: America, once the home of the world's best-fed, longest-lived people, is now a divided nation made up of a rich elite and a large underclass of poor, ill-fed, often obese, men and women who are dying early.
In another newly published paper, statisticians at Boston College reveal that in France, Japan and Switzerland, men and women aged 65 now live several years longer than they do in the US. Indeed, America only just scrapes above Mexico and most East European nations.
This decline is astonishing given America's wealth. Not only is it Earth's richest nation, it devotes more gross domestic product - 13 per cent - to health care than any other developed nation. Switzerland comes next with 10 per cent; Britain spends 7 per cent. As the Boston group - Alicia Munnell, Robert Hatch and James Lee - point out: 'The richer a country is, the more resources it can dedicate to education, medical and other goods and services associated with great longevity.' The result in every other developed country has been an unbroken rise in life expectancy since 1960.
But this formula no longer applies to America, where life expectancy's rise has slowed but not yet stopped, because resources are now so unevenly distributed. When the Boston College group compared men and women in America's top 10 per cent wage bracket with those in the bottom ten per cent, they found the former group earned 17 times more than the latter. In Japan, Switzerland and Norway, this ratio is only five-to-one.
Jacobs and Morone state: 'Check-ups, screenings and vaccinations save lives, improve well-being, and are shockingly uneven [in America]. Well-insured people get assigned hospital beds; the uninsured get patched up and sent back to the streets.' For poor Americans, health service provision is little better than that in third world nations. 'People die younger in Harlem than in Bangladesh,' report Jacobs and Morone.
Consumption of alcohol, tobacco and food can also have a huge impact on life expectancy. The first two factors are not involved with America's longevity crisis. Smoking and drinking are modest compared with Europe. Food consumption is a different matter, however, for the US has experienced an explosion in obesity rates in the past 20 years. As a result, 34 per cent of all women in the US are obese compared with 4 per cent in Japan. For men, the figures are 28 and 2 per cent respectively.
'US obesity rates jumped in the 1980s and 1990s, and the vast majority of the population affected by obesity had not yet reached age 65 by 2000,' state the Boston group. 'As the large baby boom cohort begins to turn 65 in coming years, a stronger connection between obesity rates and life expectancy may emerge.'
In other words, as the nation's middle-aged fatties reach retirement age, more and more will start to die out. Life expectancy in the US could then actually go into decline.
© Guardian Newspapers Limited 2004