Bad news, but probably no surprise to parents, when it comes to young children and vegetables: A government study showed fifth-graders became less willing to try vegetables and fruits when more were offered as free school snacks.

Older kids in the same study upped the amount of fruit they ate, but there was no change in their vegetable consumption.

The study results are somewhat disappointing for champions of getting more fresh produce into school lunchrooms.

They show that simply offering children fruits and vegetables isn’t enough, said Howell Wechsler, director of adolescent and school health with the U.S. Centers for Disease Control and Prevention. The CDC sponsored the research.

The study is one of the first to measure the success of the Fresh Fruit and Vegetable Program, a federal initiative providing grants to schools to help them buy more produce and improve the eating habits of U.S. children.

“This is very consistent with other studies, where we have seen that programs in schools have been able to increase fruit consumption,” but have not improved vegetable consumption, said Wechsler.

Kids love sweets, and junk food is plentiful in schools, according to past surveys.

The fifth-graders’ results were a little surprising, said a spokeswoman for U.S. Sen. Tom Harkin, the Iowa Democrat who authored the bill creating the program.

“He’s visited a lot of schools that participate in the program in Iowa, and anecdotally, he received positive feedback from kids and teachers alike,” said Maureen Knightly, of Harkin’s office.

“It’s the nature of science that we learn a little bit at a time,” she said, and the senator looks forward to more research.

The program, funded by the U.S. Department of Agriculture, started as a pilot in four states in the 2002-03 school year. In 2004, Congress made it permanent and expanded it to more states, including Mississippi.

The CDC study focused on five Mississippi schools in 2004-05 that served fresh produce as snacks. Among the most common offerings were apples, tangerines, pears, carrots, celery and sugar snap peas.

In both fall and spring, researchers surveyed 725 students in grades 5, 8 and 10. They didn’t ask the fifth-graders what they actually ate, because “history has shown that you can’t trust them” at that age to be accurate, Wechsler explained.

Instead, the researchers asked the kids, on a scale of 1 to 5, about their willingness to try new produce. The fifth-graders’ score for willingness to try new fruits dropped from 4.06 to 3.89 during the school year, and from 3.42 to 3.22 for new vegetables.

Eighth- and 10th-graders were asked the same questions, and also were asked what they ate. Their preference for eating fruit rose, and their consumption of fruit jumped from 1 serving a day to 1.6.

Their consumption of vegetables, however, held steady at about 2.8 servings a day. The government recommends five servings of fruits and vegetables daily, and the older students in the study came close to getting that.

The results are not surprising, said Alice Ammerman, a nutrition professor at the University of North Carolina School of Public Health.

“Anybody who has kids has seen what seems to be sort of a ‘shut-down period’” between infancy and middle school, she said, referring to a lack of interest in new foods.

Studies show that vegetables are a particularly hard sell, and anecdotes suggest many don’t really develop a taste for healthy foods until college age, experts said.

A key to getting kids to eat vegetables is creative presentation such as ‘ants on a log,’ using peanut butter and raisins to fill celery stalks, Ammerman said. Involving children in gardening and food preparation also seems to raise their interest, she said.

Wechsler said the study shows that providing kids fruits and vegetables for snacks is only partly successful and companion efforts are also needed. “This intervention shows great promise, but on its own is not enough to turn the corner,” he said.