ATLANTA – Gwinnett County Schools nutrition and procurement coordinator Karen Hallford knows students don’t much care for whole fruits and vegetables, and they seldom eat cheese stuffed pizza crust.

Hallford and other cafeteria workers in the district regularly pick through students’ finished lunch trays to see what going in the garbage, 11 Alive reports.

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“We know what our kids take when they come down the serving lines, we have a really good picture of what’s put on the tray, but we want to know what they’re actually consuming,” Hallford told the news site.

“We randomly select trays as kids are finished with their meals, put them off to the side and then analyze.”

The effort lead to the realization that students will take whole fruits and vegetables, as required by the federal government’s most recent school food regulations, but they don’t usually eat it. They also don’t eat cheese stuffed pizza crusts, officials said.

Those findings allowed Hallford and her staff to make changes to save cash, like going with cheaper non-stuffed crust pizza. They’re also cutting up fruits and vegetables in hopes students will actually eat some of them, according to the news site.

“We want to keep it exciting and refreshing and you know get them into our cafes,” she said.

Recruiting and keeping students in the National School Lunch Program has been a serious challenge for schools across the country in recent years as the federal government – lead by first lady Michelle Obama – has imposed increasingly restrictive regulations on calories, fat, sugar, sodium, whole grains, and other aspects of school lunches.

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Since the first round of the most recent regulations went into effect in 2012, more than 1.2 million students have dropped out of the federal lunch program to eat food from home, or not at all.

At Gwinnett County Schools, Georgia’s largest school district, about 120,000 out of roughly 1765,000 students eat lunch from school cafeterias – about double the national average of 30 percent, according to ABC 13.

The school trash findings there are similar to two separate, more sophisticated studies conducted recently by Johns Hopkins Bloomberg School of Public Health and the University of Vermont.

With the Johns Hopkins study, “Researchers observed 274 children in kindergarten through second grade in 10 New York City public schools as they selected from the offerings during one lunch period when a chicken-and-vegetable entrée was on the menu,” according to a news release.

“They watched to see whether each of the six-through-eight-year-olds chose a fruit, vegetable, whole grain, low-fat milk and/or a lean protein, taking before and after photos of the trays,” the release states. “They found that while 75 percent of the kids chose the lean protein (the entrée), only 58 percent chose a fruit and 59 percent chose a vegetable. And among those who put the various types of food on their trays, only 75 percent took even a single bite of the protein, while only 24 percent ate a bite of their vegetables.”

Johns Hopkins researcher Susan Gross said the results expose the flawed logic in the government’s current approach in attempting to force students to eat healthy.

“We have been thinking that if young children choose healthy food, they will eat it,” she said. “But our research shows that is not necessarily so.”

That’s the same conclusion University of Vermont researchers came to when they used digital photos to analyze school lunch trays at two northeast elementary schools on 21 visits before and after the federal school food restrictions were implemented.

Researchers discovered “that while children placed more fruits and vegetables on their trays – as required by the USDA mandates put in place in 2012 – they consumed fewer of them,” CBS News reports.

“The amount of food wasted increased by 56 percent, the researchers found.”

Nationally, experts believe the latest federal food regulations equate to a $1 billion increase in school food waste.