Paige Luster is a happy, healthy, 4-month-old infant, which is to say adorably chubby.

And parents Renee and Aaron Luster wouldn't dream of restricting her feedings to change that.

"We're happy about the way she is," Renee says. "She's a baby. That's how it's supposed to be with babies. They get chubby and then they get long, and their weight gets to be what it should be."

That's what happened with their first child, Seth, 3. His favorite snacks are grapes and strawberries.

Mom and Dad expect it will happen with Paige, too, as long as they continue to nourish their kids sensibly. The baby is breast-fed and just beginning to sample a bite or two of solid food at the family dinner table in Gilbert, Ariz.

RING THE ALARM

If the mere suggestion of putting little ones like Paige and Seth on a diet makes you cringe, you're not alone.

Some doctors and nutritionists, seeing kids whose eating has been restricted by the adults in their lives, also are alarmed. They fear that the nation's campaign against childhood obesity is backfiring, starting kids on a lifetime of secret eating, yo-yo dieting, eating disorders and feelings of worthlessness.

In recent years, grown-ups' decades-long battle of the bulge has widened its aim to target kids and teens.

Former President Clinton and California Gov. Arnold Schwarz-enegger put aside political differences to declare war on childhood obesity.

Schools have changed menus and offerings in vending machines, and some have started recording students' body mass index on report cards.

Even Cookie Monster, the "Sesame Street" Muppet, has weighed in on the issue, singing, "A cookie is a 'sometimes' food."

Now, says registered dietitian and family therapist Ellyn Satter, "more and more of the hysteria is being focused on birth weight and infancy. I've talked with women who want to manage their weight gain during pregnancy, and if their babies turn out to be at all chubby, it makes them feel bad, like they've done something wrong."

WEIGHT-LOSS HYSTERIA

Satter of Madison, Wis., is the author of "Your Child's Weight: Helping Without Harming" (Kelcy Press, 2005, $19.95 paperback).

She uses the word "hysteria" advisedly.

"I've worked with mothers who have been scared to death about eating when they're pregnant," she says. "I've worked with the children of people who've been afraid to feed them and have restricted their eating from the time they've been small.

"All of this has made (these children) weight- and food-preoccupied, desperate to eat and strongly prone to eat as much as they could, whenever they could."

No one would deny that being overweight poses risks to physical and emotional health or that increasing numbers of American youth are facing those risks.

The prevalence of overweight kids ages 6 to 11 has more than doubled, to 18.8 percent in 2004 from 7 percent in 1980, according to a study reported last year in the Journal of the American Medical Association.

In kids ages 12 to 19, it has more than tripled, to 17.1 percent from 5 percent.

What's troubling to some are the overt approaches to helping these kids — the focus on "red-light" foods, the after-school nutrition classes, the forced gym memberships, the public tsk-tsking.

Phoenix family physician Michelle May says a backlash isn't surprising when grownups nag kids about what they eat and make them feel unacceptable the way they are.

She sees the results in adult dieters, and she saw them in herself after starting the first of what would be many diets when she was about 11.

WATCH WHAT THEY EAT

"In retrospect," she says, "I really wasn't that overweight. But I started myself on a path of worrying and dieting and restricting. It created a situation where I was sneak-eating and too focused on foods, either trying to restrict them or, as a counterpoint to that, overeating them."

May, author of "Am I Hungry? What to Do When Diets Don't Work" (Nourish Publishing, 2004, $15.95 paperback), learned something valuable by watching her son and daughter at mealtime when they were young.

"They ate when they were hungry and stopped when they were full," she says.

"They weren't worried about food. They didn't obsess about food. When they weren't hungry, they didn't even think about food."

Without parental hovering, they naturally ate the right foods in the perfect amounts for them. Now 16 and 12, fit and active, they take pleasure in all kinds of nutritious food.

And there's no guilt when they decide they're in the mood for something sweet.