Short school lunch periods might be enticing students to eat too fast, skip meals, or choose fast-food or vending machine munchies, state and district child nutrition experts say.

And that, they fear, can hurt kids' health — and their academics.

"If they feel they don't have enough time to eat, (students) don't participate in the lunch program. They race by a vending machine or leave campus or just don't eat. That's what we believe," said Warren Gaddis, assistant director of child nutrition for the State Office of Education. "I certainly think that when they stop by a vending machine and buy a Coke or a candy bar . . . they're not likely to be in much condition to pay attention in class."

A State Board of Education committee shares the concerns. Last week, it asked State Office of Education staffers to probe how much time schools give for the midday meal. Depending on what comes of it, the board could mandate the length of lunch periods.

Child nutrition is a hot topic nationwide.

One-fourth of all Utah kindergartners through eighth-graders are at an unhealthy weight and almost 12 percent weigh in as "obese," according to a Utah Department of Health study released last year.

Doctors are finding adult-onset diabetes and other grown-up ills, including high blood pressure and clogged arteries, in adolescents.

The Utah Legislature, which convenes later this month, is expected to debate a bill that would ban minimal-nutritional-value foods from being sold in elementary schools. The bill, sponsored by Rep. Pat Jones, D-Cottonwood Heights, was crafted with input from Primary Children's Medical Center, the Utah Medical Association, the Utah Nurses Association and Action for Healthy Kids.

Health organizations, including the American Dietetic Association, report that nutrition affects student learning.

Still, in the day of increased school accountability, class time is battling meal time, and winning, said Marilyn Clayton, director of nutrition services for Jordan School District.

"They want them to be in class longer," Clayton said. "A lot of the schools have 23 minutes from fourth to fifth period, and (students) have to go to their locker, then lunch, then back to the lockers" because backpacks aren't allowed in lunchrooms. "And (that's) not giving them enough time to eat."

Ten rural and urban high schools contacted by the Deseret Morning News have lunch periods ranging from 25 minutes at Piute High, to 40 minutes at Springville and Tooele high schools. Bear River and Ben Lomond high schools give students 30 minutes to eat. Riverton and Panguitch, 33 minutes; Cyprus, Delta and Layton, 35.