Supersize me: overeating may be just as big a problem globally as lack of food, but our concern and compassion for those who are fat is usually less than generous. (culture in context).

FAT IS FUNNY AGAIN, AT LEAST IN HOLLYWOOD. Last year tinseltown served up a trio of romantic comedies about the trials and tribulations of fat girls and the superficiality of the cads who can't see their inner beauty. In Shallow Hal, America's Sweethearts, and Bridget Jones's Diary, Gwyneth Paltrow, Julia Roberts, and Renee Zellweger play portly to porterhouse versions of their svelte selves and entertain audiences with jokes about big underwear and midnight binges. (Curiously enough, there weren't any fat jokes when Tom Hanks blew up to Hindenburg proportions in Cast Away--which is exactly what these actresses would become if they really supersized themselves.) We haven't seen Hollywood so jolly about big women since Shelley Winters entertained us in The Poseidon Adventure.

Still, the last laugh in these fat jokes may be on us. America now has the highest percentage of obese citizens. A study released last September indicates that nearly 40 million American adults are obese, meaning that one in five grownups in this country have become grown-outs by adding a third more tonnage to our weight. An additional 6 million are considered "superobese," weighing about 100 pounds more than they should, and more than half of us (56.4 percent) are overweight.

For decades we've been devouring the latest diet and exercise books like they were chocolate truffles and consuming billions of dollars' worth of exercise equipment and health club memberships. And yet the rate of obesity among U.S. adults has doubled since John F. Kennedy's White House sounded the first alarms about America's unfitness. In the past decade the national obesity average has swelled from 12 to 20 percent. In Mississippi a quarter of the adults are obese, and only Colorado has an obesity rate of less than 15 percent.

The picture among our children isn't much brighter. The obesity rate among U.S. youth is twice what it was two decades ago. One eighth of all American children are currently obese; a quarter of them are overweight. James Hill, a nutritionist at the University of Colorado, notes that "we've got the fattest, least fit generation of kids ever."

Much of the blame for our swelling ranks of fat can be placed on our cars, TVs, and fast food restaurants. Americans are ever more sedentary, getting less exercise and driving (not walking, running, or cycling) everywhere. We spend most of our recreational time in front of a TV or computer screen, and we've been getting larger and larger portions of our meat and potatoes (without fruit or green vegetables) from the local burger or pizza franchise. Eric Schlosser notes in Fast Food Nation (Houghton Mifflin) that in 1970 Americans spent $6 billion on fast food. In 2000 we spent $110 billion.

Teenage boys in this country now drink twice as much soda as milk, and Americans consume about a third of their calories outside the home. At the local fast food franchise they've been "supersizing" our meals (and our waists), providing increasingly fattening portions of fries and soda to accompany our cheeseburgers. In the 1960s an order of fries at McDonald's contained 200 calories. Today's supersized version has 610. A supersized soda (32 ounces) has 26 teaspoons of sugar or 310 calories. A healthy adult has to run one mile to burn off 100 calories.

And as globalization has brought America's way of life and eating to the rest of the planet, obesity has become an international plague. Lester Brown's Worldwatch Institute reports that a majority of adults in Russia, Britain, and Germany are now overweight, as are more than half of the adults in Europe between the ages 35 and 65. In China 15 percent of the adult population weighs too much, and in Japan a third of all men in their 30s are overweight. Even in Brazil, 38 percent of the adults are carrying too many pounds. According to Brown, "The number who are overnourished and overweight has climbed to 1.1 billion worldwide, rivaling the number who are undernourished and underweight."

THE COSTS OF THIS EPIDEMIC ARE OVERWHELMING. Each year nearly 300,000 Americans die as a result of obesity (making this the No. 2 killer of American adults), and the nation's annual health care bill for obesity runs about $280 billion, not counting the $33 billion we spend on diets and weight-loss programs. Grossly overweight people are four times as likely to die young as those of normal weight, and severely obese children as young as 6 are now dying of heart attacks caused by their weight. The number of cases of adult diabetes in this country has climbed from 9 to 15 million since 1991. "If we continue on this course for the next decade," notes Jeffrey P. Koplan, director of the Centers for Disease Control and Prevention, "the public health implications in terms of both disease and health care costs will be staggering."

On the global level, Peter Kopelman of the Royal London School of Medicine says, "Obesity should no longer be regarded as a cosmetic problem affecting certain individuals, but [as] an epidemic that threatens global well-being." And Dr. Van S. Hubbard of the National Institute of Diabetes and Digestive and Kidney Diseases claims that overeating is a larger problem worldwide than is food deprivation, costing immense amounts in health care.

BUT WHAT IS PERHAPS MOST STRIKING about this obesity epidemic is the way in which it is concentrated among the poor. We are used to thinking of the poor as hungry, and indeed more than 800 million poor on this planet are undernourished or starving. But in the U.S. and many other nations, this life-threatening epidemic of obesity is disproportionately threatening the poor.

Fat is no longer just a feminist issue. It is also a class issue. Study after study indicates that minorities and the poor are more likely to be obese than their white middle- and upper-class counterparts. Sixteen percent of whites making $50,000 a year are obese, while nearly 23 percent of those making $15,000 are. Meanwhile 22.5 percent of blacks earning $50,000 are obese, but 34 percent of those making $15,000 are.

Lack of access to supermarkets with ample produce sections, safe parks with recreational facilities, or schools with adequate physical education programs, as well as greater reliance on TV as the baby sitter and recreation of choice and a growing dependence on fast food franchises that serve "supersize" meals all contribute to higher obesity rates among our nation's poor. People in poorer neighborhoods are attracted to food that is cheap, convenient, and easy to store, so they load up on canned and bulk goods and don't buy a lot of fresh vegetables or health foods. These choices made good sense when Americans were more active and less sedentary, but today a preference for starchy and fatty foods can be life-threatening.

OUR BIBLICAL AND CHRISTIAN TRADItions haven't taught us much sympathy for those who are fat. Jeremiah and Amos blasted the idle rich for cheating and oppressing widows and orphans, calling them fattened cows, sleek and bloated with their wealth. And Christian monks and mystics often embraced ascetical fasts that made them as thin as El Greco saints.

But in the time of the Bible and early Christianity, only the rich were fat. Today the poor and minorities are more likely to face the health threat of obesity than the rich or middle class, and we need to rethink our response to this issue.

We need to ensure that the ways in which we live and eat (and work and commute and recreate) do not foster a plague of obesity (and diabetes and heart disease) on the houses of the poor. We need to make certain that rich and poor alike have the resources and training to make good choices about their diet, and that all of our children have safe places to play and good programs to help them build their bodies as well as their minds. After all, a body is a terrible thing to go to waist.

PATRICK MCCORMICK, an associate professor of Christian ethics at Gonzaga University in Spokane, Washington.