Nate Bleszinski used to grab three cookies every time he passed the kitchen cabinets. At McDonald's, he'd order a quarter-pounder with cheese and a six-piece chicken-nugget meal. On pizza night, he might have four or five slices. And when his mother, Marianne, cooked a well-balanced meal of chicken, rice and veggies, he'd eat mostly rice — and lots of it.

"I didn't think about it," says Nate, an 11-year-old from Glastonbury, Conn. And although many kids can eat this way and stay thin, Nate can't. As he got older, he began to talk about losing weight. He plays hockey, and he knew he could improve if he could skate faster.

Nate's mother says that last fall, "all of a sudden he was looking a little heavier, and we thought: What are we going to do?"

It was important for him to learn healthful eating habits now, she says.

Nate's family knew they would need help to stay on track. They went to Diminishing Dimensions in Glastonbury, where they have been working with co-owner Rita Anderson. Companies and programs devoted to weight loss and healthful eating are seeing more children and teenagers enrolling.

Experts say that for children the emphasis should be on learning more healthful eating habits — not losing weight or dieting.

"We don't want children to be preoccupied with weight," says Dr. Kelly Brownell, director of the Rudd Center for Food Policy & Obesity at Yale University. Instead, he says, the emphasis should be on "health and vitality."

"Focus on their ability to do what they want in life," he says. "So, for example, if a child wants to do a sport or wants to do better in school or have more fun playing with their friends, all of these things are important."

Margaret Grey, dean of the Yale School of Nursing, agrees.

"One of the things we've learned is that it doesn't do a lot of good to talk about weight, and it doesn't do a lot of good to beat up kids about it."

As part of a New Haven middle school program that addresses nutrition and health, Grey says, "we talk a lot about having energy to do all the things you want to do, being able to fit into fashionable clothes. Talking about the health scare doesn't do any good with kids."

Often, though, it is the health scare that gets parents' attention. Rene, a mother of four in Farmington, Conn., who asked that her last name not be used, says she worries because she watched her overweight mother struggle with heart problems. Two of her sons, Chris, 16, and Pat, 14, use their weight to some advantage on a football field, but both felt they weighed too much. They tried Weight Watchers but didn't like the weekly weigh-ins and complained that they were always hungry. Then they contacted Pam Oliver, owner of Body Transformers in Rocky Hill, Conn. On a recent Sunday, the boys sat with Oliver in their living room.

"I've given you a lot of cereal, and it's quick and easy, but this week what I'd like to do is to put in more protein," Oliver told the boys. Oliver designed individual meal plans for Chris, Pat and Rene, who also wished to lose weight — with similar dinners that allowed for individual preferences.

Experts say that for children to lose weight, it has to be a family endeavor.

With their busy schedules, Rene said her family too often relied on quick but calorie-heavy meals such as pasta or chicken nuggets and fries for dinner. Now they have more healthful meals, including low-fat quesadillas, turkey burgers and chicken strips with Shake 'N Bake.

Oliver encourages them not to look at the scale but to develop healthful habits and the trimmer body will follow. Since the program began in November, the boys say they've each lost about 10 pounds while Rene has lost 20.

Similarly, Nate has done well working with Anderson at Diminishing Dimensions. As part of her program, Anderson has a notebook full of kid-friendly explanations of proper nutrition, exercise and food labels and has written homework to help reinforce the lessons.

Since he started the program about two months ago, Nate hasn't been to McDonald's and he's eating low-fat high-protein soy crisps instead of chips, low-fat cheese, broccoli, tofu, salmon and other healthful options. His mother packs him a lunch, and when he doesn't have hockey, he lifts weights and spends time on a treadmill. The extra exercise isn't always easy, because sometimes he'd rather be out playing with his friends, but he says it's worth it. He's lost about 12 pounds.

"I feel like a stronger person and I feel a lot better," Nate says.

Perhaps the best way to help children lead healthful lives is to start when they are very young.

Since the late 1990s, Claire Dalidowitz, a registered dietitian at the Connecticut Children's Medical Center, has run a healthful lifestyle program for kids ages 6 to 9. The 12-week program includes everyone important in a child's life: parents, older siblings, daycare providers, grandparents. A physical therapist encourages physical activity, and a social worker looks at issues such as possible depression in the family.

Good nutrition, portion control and physical activity are all covered, as is less time in front of the TV. The focus is on lifestyle, Dalidowitz says.

"If we focus on weight loss, then parents do restrictive diets and kids end up binging," she says. "We try to increase fruits and veggies and decrease snacks in packages, most of which are high in fat and high in carbohydrates."