While many office workers were taking their coffee breaks, 14-year-old Michelle Pagan was having lunch.

Not that she was ready for her peanut butter sandwich and bag of pretzels at 10:20 a.m.

"Am I hungry? Not really," Pagan said during her lunch period at Great Valley High School in suburban Philadelphia. She might save the pretzels for later and won't have "another whole meal, just snacks."

Students in Salt Lake high schools will be on a similar lunch schedules by the end of this spring, after the fire marshal ordered split lunch periods due to overcrowded corridors.

"We just had too many kids out in the cafeteria and commons area," said Diana Albiston, field nutrition supervisor over secondary schools in Salt Lake District. "When you have 2,500 kids in school and they're all out on one lunch period it can be kind of dangerous."

East High went to the split schedule in January, and Highland and West will follow soon this spring.

The Salt Lake high schools join three high schools in Davis and a majority of secondary schools in Jordan school district that have two lunch schedules — some are even split into three.

But researchers at Penn State University fear that early lunches and single-food sales may contribute to bad eating habits.

In a survey of schools, they found that those with lunch periods starting at 10:30 a.m. or earlier have higher a la carte sales than those that have later lunches. The biggest sellers typically include pizza, burgers, cookies and pastries.

There are some healthy choices, like salads, too. But the problem is that many children are having to make do until dinner, said Claudia Probart, a nutrition professor at Penn State.

"When this kind of lunch isn't normal eating behavior, kids develop certain survival strategies through the rest of the day," Probart said.

Many students say they feel like they're grazing.

Albiston, however, said there are indications some students are actually eating better. Since East implemented the split schedule the number of students participating in school lunch has increased.

"We have gone from feeding around 500 to somewhere around 700 at East since we switched schedules," Albiston said. "Before, a lot of them would go off campus and get food that would probably not be as healthy . . . so some are eating healthier."

But East High principal Robyn Roberts said the students are learning to adjust — some bring snacks, some will eat directly after school. It's the social aspect that has students in Salt Lake City complaining.