Never-Ending Battle of the Bulge Takes Its Toll : Health: An estimated 34 million U.S. adults are obese. Americans spent more than $30 billion trying to lose weight or keep it off last year.

In childhood, chef David Liederman recalls his brother and his stepfather lunging--forks first--toward the last pork chop. Dad speared the brother, and in the chaos, Liederman came up with the chop.

“We were so eager to get to the portion that we barely tasted what we were eating and whatever hit the table was devoured as if hit by a buzz saw,” he said.

Liederman was off on a decades-long journey of devouring that eventually led him to map trips through France aimed at hitting as many three-star restaurants as possible. At 38, he topped 300 pounds.

He opened two New York City restaurants and a chain of chocolate chip cookie shops, called David’s Cookies. And though he has dropped 100 pounds, kept it off for three years and written a book, “David’s Delicious Weight-Loss Program,” he remains obsessed with food.

“My biggest project in life is keeping from getting fat,” said Liederman, now 41. “If you believe the way I do that compulsive eating is not only a sickness but an addiction, how do you get rid of the problem without spending the psychological energy?”

One therapist compared his situation to “psychological tyranny.” But Liederman, for now, is content.

He carries a pocket diary everywhere, recording every single taste of food in tiny little letters, down to the spoonful of clear broth and mushroom soup tasted at his Broadway Cafe. He is fanatic about daily exercise, usually with a trainer. At 5-foot-11 and about 180 pounds, he looks healthy and moves fast.

“My goal in life is for someone to say, ‘You look terrible, David. Eat something,’ ” he said.

Millions of Americans feel an immediate affinity with those words. Half the adult women and 30% of adult men in this country are on a diet. Americans spent more than $30 billion trying to lose weight or keep it off last year, and a congressional committee is investigating the industry.

Still, an estimated 34 million American adults are obese--that is, they weigh at least 20% above their ideal weight.

“The aesthetic ideal is so lean, and now athletic, that it’s simply impossible for many people to attain that ideal,” said Kelly Brownell, co-director of the Obesity Research Clinic at the University of Pennsylvania. “Many people lose to a healthy weight, but they don’t feel satisfied.

“They push beyond to the aesthetic ideal, and their body fights back, their body wins, and they end up at a higher weight.”

Americans turn to self-help books, relaxation techniques, Overeaters Anonymous, Weight Watchers, modified fasts, liquid diets, liposuction, wired jaws, stapled stomachs, grapefruit, acupuncture, hypnotism, fatty photos on the refrigerator, fake fats, artificial sugars, jogging, spas, aerobics, Stairmasters, gyms, drugs.

Dieting is part of the mainstream; going off a diet is failing.

That philosophy is part of the problem, according to therapists who say food represents other problems. If people learned to eat to ease hunger for food, rather than hunger for love or something else, most eventually would reach a weight that’s good for them, they say.

Financially, emotionally and physically, Americans are paying for being so persistently and obsessively focused on an ideal they most likely will never attain. Why?

For one thing, women, and men to a lesser extent, are victims of a culture that worships a sylphlike figure to the virtual exclusion of other body types.

“You can’t work with women and not work with eating problems, body image,” said Andrea Gitter, a therapist at the Women’s Therapy Center Institute in New York City who specializes in eating problems.

“It touches on everybody’s insecurity. The underlying message is that you’re not OK as you are,” said Gitter, who was a compulsive eater until she learned to eat to satisfy physical hunger rather than to stave off guilt, loneliness or other emotional longings.

Women often believe that if they are thin, if they control their appetites, they will be happy, loved and respected, Kim Chernin writes in “The Obsession.”

Losing weight, Hillel Schwartz argues in his book “Never Satisfied,” has become “the modern expression of an industrial society confused by its own desires and therefore never satisfied.”

The obsession strikes girls early. A 1986 study in San Francisco found that of 500 girls in fourth grade through high school, almost 80% of 10- and 11-year-olds reported dieting to lose weight.

And many parents have overreacted to researchers’ warnings that television-addicted children would grow obese; nutritionists had to admonish parents not to take all the fat out of their children’s diets.

That provides a glimpse at one of the strange aspects of America’s obsession with weight: One need not be overweight to live a lifetime of dieting.

Few people feel content with their bodies.

A sort of daily tally sheet is set up: An hour pedaling the exercise bike equals a dish of Haagen Dazs. No breakfast makes fries OK at lunch. A husky guy buys a bag of chips, stuffs a few handfuls in his mouth and tosses the bag in a sidewalk trash bin before he eats too many.

Every ounce Oprah Winfrey or Liz Taylor gain and lose is watched by an America gleeful that the famous are no better than we are at keeping thin.

Most people believe thin people get paid better, get more dates, live longer and have fewer diseases. But Chernin notes this sense of well-being is precarious, since most of those who lose weight put it all back and more.

The solution remains as elusive as the diet that lets you eat what you want and lose weight.

“The history of the diet industry in America probably represents one of the most astounding triumphs of 20th-Century capitalist enterprise,” Joan Jacobs Brumberg writes in “Fasting Girls.”

“There is nothing that isn’t sold without a thin female body next to it,” says Susan Gutwill, also with the Women’s Therapy Center Institute. “It’s really immoral. It’s criminal in a very serious way.”

Research may provide more clues to the causes of obesity, but one fact doesn’t change: To lose weight and keep it off, you must develop healthful eating and exercise habits for good, the experts say.