Catherine Cook-Cottone walked through the front lines of the war over children's stomachs: the supermarket cereal aisle.

"As a parent, you don't even realize how much strategy you're facing," said Cook-Cottone, a psychologist. She pointed out where the most sugary stuff was, in boxes emblazoned with colorful animals and movie heroes' faces: on the bottom row, right at eye level for its intended audience.

One box of brightly colored Crunch Berries won't make your child fat, but making such food a habit carries costs beyond the grocery bill. "You're thinking you're keeping your kid happy," said Cook-Cottone, an associate professor in the University at Buffalo's Graduate School of Education. "It's not always easy to say no."

Childhood obesity has been declared an epidemic threatening American children, and first lady Michelle Obama has tried to make improving school lunches a key part of the national response. Meanwhile, food manufacturers are spending billions of advertising dollars every year to push their products into the breakfast bowls and lunchboxes of American children.

Caught in the middle, parents are left trying to figure out what to do. With the start of another school year, The News asked two local experts for tips on how parents can pack healthy school lunches and raise healthy eaters.

Child nutrition authorities agree on what children need to eat to thrive. The food pyramid model, recently updated by federal experts, lays it out: lots of vegetables and fruit; some proteins from meat, fish or vegetable sources; carbohydrates from bread, pasta or grains; with a little sugar, oil, salt and so on.

How does that translate to packing lunch? Take it from registered dietitian Sheila Flavin, who has 20 years' clinical experience, taught graduate nutrition courses and raised three children.

* Know the standards. "You have to have a protein source: peanut butter, or hummus, if you're vegetarian," Flavin said. "Tuna fish, or lower processed cold cuts like ham, turkey or even roast beef."

They absolutely need carbohydrates, Flavin said, like bread, cooked pasta or crackers. A calcium source, like milk, cheese or a lower-sugar yogurt. Fruit, like a fruit cup or piece of fruit; vegetables, such as carrot sticks; or both.

Flavin isn't a prude when it comes to lunch-packing. "I think lunch should could contain a treat," she said. "A couple cookies or some pretzels, something like that."

Or a juice box. While other authorities consider it a fruit serving, "I count it as a treat," she said. "Excess calories, minimal nutritional value." In a time when "most kids are getting too many calories, and too much sugar," she said, those decisions add up.

* Limit sugar. Juice boxes aren't the enemy -- sugar is. "Americans consume too many calories, and we consume too much sugar. That's the bottom line," Flavin said.

That's partly because kids are born craving sugar. Cook-Cottone, co-author of the upcoming book "Eating Behavior from Health to Disorder," is raising two daughters, 10 and 12.

Despite everything their nutritionist psychologist mother has done, her daughters would choose candy over cookies every chance they got, she said. "If it has flour in it, it's not sweet enough."

The emphasis is on limiting -- not eliminating -- sugar. Flavin suggests feeding children a lower sugar cereal like Cheerios, and if you have to, letting kids add a teaspoon of sugar. "A little bit of sugar is fine," she said. "You will always put in less sugar, less salt and less fat than the highly processed products from manufacturers, in general. That's my approach."

* Walk the walk. "Parents are the most powerful influence on children's lives," Cook-Cottone said. "It's not fear, but the modeling that we do."

If you care about your children eating well, you have to eat a healthy diet yourself. "You can't have them following these nutrition guidelines, then mow through a box of Oreos," she said. "It won't work. Kids can smell fraud."

* Take a hard look at school lunch. Many school programs have made strides in offering delicious, wholesome lunches, even though many face harsh budget constraints. "I've been in this field a long time, and there's more focus now on school lunch and on improving the school lunch than I've seen in 30 years," Flavin said.

But many use processed, fortified items to meet nutritional goals, Flavin said. "Food manufacturers will put together products that are supplemented with certain vitamins so they can meet the requirements," she said. "So you get these things like honey buns that are just junk, but they have the added vitamins and minerals that the school lunch directors need to meet the guidelines."

Look at the school lunch menu, Flavin suggested. Decide what ones your child wants, what you can afford, and how often you have time to pack a lunch.

"My big rule is you don't have to be 100 percent of anything," she said. "You don't have to take a lunch every day to school. But it's a great idea for children to take some responsibility and pack their own lunch, to take responsibility for what they're going to eat, too."

* Get between advertisers and your kids. The business of marketing sugary products to children and their parents has exploded since 1982, when the appearance of Reese's Pieces in "E.T." jacked up sales by 65 percent.

Research suggests that the average American child sees an estimated 20,000 television commercials annually, about half for food products, Cook-Cottone noted. Limiting screen time to two hours a day can help, she said.

She believes parents should watch TV with their kids, to teach them marketing self-defense. So she talks over the commercials, pointing out their implied messages and dream-world logic. "They think it's cool to know that," Cook-Cottone said, "sort of the inside scoop."

* Bend but don't break. Researchers studying the effects of parenting styles on children's nutrition and eating habits found that rigid authoritarians and eat-what-you-want parents got the worst results, Cook-Cottone said.

What worked best, the study found, was spelling out the rules and the reasons, sticking to them most of the time, and working on acceptable compromises.

Flavin said that at times, she used to let her kids eat sugary cereal on weekends. Even though she found them repulsive, she would buy her kids Lunchables on occasion.

"They got those for their birthday, or a field trip," she said. "I would tell my kids, 'These are gross, but you can have it -- it's your birthday.' "

* Do the work to decode nutrition information yourself. Marketers are trying harder than ever to dress up sugary products with wholesome camouflage. Labels boasting of vitamin and fiber content can camouflage junk.

"Today's granola bars, breakfast bars and Power Bars are glorified cookies and glorified candy bars, for the most part," Flavin said. "The sweet and salty ones, with the nuts and frosting on it, I love them. But, whoa -- this is a candy bar, even if it's yogurt-frosted."

Sometimes it takes a moment, looking at nutrition labels and doing the math, to decide which product is best for you.

"It takes some thinking," said Cook-Cottone. "The advertisers aren't going to do it for you."