The new U.S. Department of Agriculture (USDA) rules aim to boost the nutritional quality of the federally subsidized meals consumed by roughly 32 million U.S. schoolchildren daily.

The rules represent the first major revision of school meal standards in more than 15 years and are intended to combat the nation's childhood obesity crisis. Nearly one in three children in America is overweight or obese.

The overhaul comes just months after U.S. lawmakers acted to maintain pizza's status as a vegetable and killed proposed limits on weekly servings of starchy foods like potatoes.

In addition to doubling produce servings, the new guidelines call for fat-free and low-fat milk only, child-appropriate portion sizes and reductions in sodium, saturated fat and trans fats.

The changes were adopted under the Healthy, Hunger-Free Kids Act (HHFKA), which was championed by first lady Michelle Obama and signed into law by President Barack Obama in 2010.

The new standards will be largely phased in, starting in the 2012-13 school year. They are expected to cost roughly $3.2 billion to implement over the first five years.

HHFKA authorized more funding to schools to help cover the extra costs associated with the menu changes.

The USDA gives school districts money for student lunches and breakfasts through its $18 billion school meals program.

The majority of children participating in the program are eligible for free or reduced-price meals. The USDA said 63 percent of lunches and 89 percent of breakfasts served are free or at a reduced cost.

FRIES WITH THAT?

Lawmakers altered the school lunch guidelines in November, when they barred the USDA from limiting the weekly servings of french fries and ensured that pizza continued to be counted as a vegetable portion because of its tomato paste.

Trade groups representing frozen-pizza sellers like ConAgra Foods Inc and Schwan Food Co, as well as french fry distributors McCain Foods Ltd and J.R. Simplot Co, were instrumental in blocking rule changes affecting those items.

Those actions caused a public uproar but won cheers from critics of the HHFKA rules, who cited the new regulations as an example of overreach by federal bureaucrats meddling in the food decisions of families.

"What we are announcing today are science-based rules and regulations that are going to substantially improve the meal qualities across the United States for children," USDA Undersecretary for Food, Nutrition and Consumer Services Kevin Concannon said on a conference call.

Margo Wootan, nutrition policy director for the nonprofit Center for Science in the Public Interest, said the new standards were a big improvement, despite food industry lobbying and the congressional revamp.

"Despite industry lobbying and congressional meddling, the new school meal standards are one of the most important advances in nutrition in decades," she said.

The Environmental Working Group said the adjustments could also curb healthcare costs since they may help reduce medical bills related to diabetes and other obesity-related chronic diseases.

"A healthier population will save billions of dollars in future healthcare costs," said Dawn Undurraga, EWG's staff nutritionist.

As an example of a new meal, the USDA said an elementary school lunch might consist of whole-wheat spaghetti with meat sauce and a whole-wheat roll, a vegetable mix of green beans, broccoli and cauliflower, plus sliced kiwi, low-fat milk, low-fat ranch dip and soft margarine.

That lunch would replace a meal of a hot dog on a bun with ketchup, canned pears, raw celery and carrots with ranch dressing, and low-fat chocolate milk.

Some school districts already have moved in the direction of the new rules. Results have been mixed.

Julia Bauscher, director of school nutrition services for Jefferson County Public Schools in Louisville, Kentucky, said her district already is serving whole-grain breads and greens like spinach, kale and romaine lettuce.

The district built acceptance by adding things gradually, working with student advisers and handing out samples of new menu items.

Bauscher acknowledged that children complained when the district started serving fewer potatoes to the 100,000 students in the meals program.

"They didn't like that so much, but they have learned to pick up something different," she said, noting that the potato-serving reductions are not required under the new rules but have been recommended by heath experts.

Some schools have had a tougher go.

Los Angeles Unified School District, one of the nation's largest, is revising its healthier lunch menus after initially missing the mark with students.

As part of the new standards, USDA also will increase the number of inspections of school menus. New guidelines for other food sold in schools, including items sold in vending machines and school stores, are due later this year.

(Reporting By Ian Simpson in Washington and Lisa Baertlein in Los Angeles; Editing by Steve Gorman, Paul Thomasch and Steve Orlofsky)

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