A recent social media trend of photographing gross-looking cafeteria meals with the hashtag #thanksmichelleobama highlights growing pains from new changes to school lunch menus nationwide.

Recent rule changes aimed at making school meals healthier may have had unintended consequences. Many kids say they find the new, healthier meals unappetizing, and many adults are beginning to question whether the overhaul was effective.

The U.S. Department of Agriculture (USDA) oversees the National School Lunch Program (NSLP). In 2012, first lady Michelle Obama helped craft new USDA guidelines that require lunches to contain more fruits, vegetables, and whole grains. The changes limit salt, sugar, fat, and calories in school meals as well.

Obama has gotten much of the flack for the program’s shortcomings, since she launched it as part of her “Let’s Move!” campaign to fight childhood obesity. Schools are obligated to comply if they want to receive federal funding through the NSLP.

Get the Details About the New Healthy School Lunch Rules Here »

Between the 2010-11 and 2012-13 school years, the number of students enrolled in the NSLP fell by 3.7 percent, or about 1.2 million children.

“Some of the new regulations are too much, too fast, and are driving students away from healthy school meals,” said Diane Pratt-Heavner, a spokeswoman for the nonprofit School Nutrition Association.

She cited a recent survey that found nearly a quarter of schools reported their meal programs operated at a net loss for six months or more. Those losses have to be made up by the district at the expense of education funds, Pratt-Heavner said.

The USDA estimated that local schools would have to absorb more than $3 billion in increased food and labor costs under the new standards. These increased costs will equal about 10 cents for each reimbursable school lunch and about 27 cents for each reimbursable breakfast in 2015. Congress has only approved 6 additional cents for lunch to meet these new standards and has passed no additional funds for breakfast.

With healthier options on the menu, students must select either a fruit or vegetable, but that doesn’t mean they have to eat them. In fact, students can decline two out of five of the lunch options offered on a given day.

A study in the journal Public Health Nutrition that looked at plate waste in 2010 found that 45 percent of elementary and 34 percent of middle school students selected a vegetable. However, of more than 500 elementary school trays studied, the students wasted more than a third of all grain, fruit, and vegetable items. Among 364 middle school students, kids left nearly 50 percent of fresh fruit, 37 percent of canned fruit, and one-third of vegetables on their trays.

Another plate waste study from 2014 observed more than 300 students. It found that most students had about 10 percent waste in every category: entree, fruits, veggies, and milk. Veggies were the most often wasted at 29 percent, and only 20 percent of kids selected vegetables in the first place. Entrees were tossed the least often — just 12 percent were thrown out.

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The goal of the new rules is to get kids eating healthier foods. Are they?

A 2013 study in the American Journal of Preventive Medicine looked at four schools in an urban, low-income school district in the fall of 2011 and 2012 — before and after the USDA rules went into effect.

Harvard School of Public Health researchers found that entree and vegetable consumption increased by about 16 percent each in 2012, compared to a year earlier. Fruit consumption stayed the same, though the number of children choosing a fruit increased from 53 percent in 2011 to 76 percent in 2012.

That doesn’t mean there was no food waste — children threw out 60 to 75 percent of the veggies they selected, and 40 percent of fruit went into the trash too. However, they didn’t waste more than normal when forced to choose a fruit or veggie.

“Students often need time to acclimate to new foods,” explained Juliana Cohen, a research fellow at the Harvard School of Public Health who conducted the study. “Rather than weakening the standards, we should focus our attention on ways that we can support school food service employees, such as providing them with more healthy commodity foods and new recipes or training opportunities that focus on these foods, so that schools can provide students with both cost-effective and good tasting meals.”

Another study published this year shows that about 16 percent of lunch trays at two schools did not contain a fruit or vegetable before the USDA rule changes. After they went into effect, however, that number went down to just 2.6 percent of trays — so perhaps selection is going up.

Many of these studies offer conflicting results: Some say kids are taking the healthier options and eating them; others say they may select them, but that doesn’t stop kids from tossing them out.

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A report presented this month at the American Public Health Association’s annual meeting by Susan Gross, Ph.D., a research associate at Johns Hopkins University’s Bloomberg School of Public Health, found that kids aren’t too keen on the USDA’s changes.

Of 274 children in kindergarten, first, and second grades in 10 New York City schools, 59 percent grabbed a veggie, but just 54 percent ate a single bite of it. Just 24 percent ate more than half of their veggies. Of the 58 percent of kids that chose a fruit, 76 percent of them did eat at least some of it.

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

The cafeteria setting could be part of the problem, Gross said. Her team found that children were more likely to finish their food if a teacher ate in the cafeteria with them and if they had a longer lunch period. They also showed that more kids ate their veggies and whole grains, specifically, when the cafeteria was less noisy.

“It may be the overwhelming atmosphere of a cafeteria that may impact how much they eat, as opposed to the food itself,” Gross said.

The scientists also noticed that young children were more likely to eat healthy food when it was cut into smaller pieces. A 6-year-old may not eat as much as an older child, and a younger child might not take a whole apple because they can’t cut it themselves. On the flip side, if apple slices are put out, children may be more likely to take them — that is, if they haven’t browned yet.

“It’s really hard to produce things mass,” Gross admitted. Some school districts have a central kitchen and then transport prepared meals out to schools, so food may be much less appealing by the time it reaches the children. “It’s not an easy process for them to keep things appetizing,” she added. Shifting to on-site preparation may be a way to get kids to select and eat healthier options, and could cut down on waste.

Some school districts do well at providing fresh choices and making sure they’re palatable. It’s harder for others, and that’s not something that officials — or even food service workers — can control, Gross said.

There is one spot of good news: If kids feel like they’re included in the process of choosing school meals, they are more likely to get on board with healthy nutrition. Gross said her experience in a cafeteria where kids were able to give input on healthy meals was that the food didn’t just get taken, it got eaten too.