An increase in fruits and vegetables offered by Minnesota high school lunch programs could be, well, fruitless if school districts don't also cut down on unhealthy snacks available to students.

Minnesota is one of 11 states where high schools offer high rates of both healthy and unhealthy snacks and a la carte lunch items, according to a new report. That can set up a conflict.

"It is very important to have fruit and vegetable offerings, but it's also pretty important to not be having those items competing with the less healthy stuff," said Erik Olson, director of food programs for the Pew Charitable Trusts, which released the report Thursday with the Robert Wood Johnson Foundation.

Minnesota ranked sixth best nationally for healthy snacks -- with 39.9 percent of high schools offering fresh fruit -- but fourth worst in a measure of schools serving cookies, cakes and similar baked goods. Nearly half of Minnesota high schools sell these sweets as snacks, according to the report, which is based on 2010 federal data.

The report stopped short, however, of recommending bans on unhealthy snacks as a strategy for reducing the rate of childhood obesity. In Minnesota, that rate has tripled over the past 20 years; 12 percent of ninth-grade boys were obese in 2010, according to the state Department of Health.

The report comes as schools across Minnesota are also modifying lunch menus to conform with new federal nutrition guidelines that require more fruits and vegetables but fewer calories and carbohydrates.

Chips or sweets are still OK if the calories and portion sizes are cut to age-appropriate levels, Olson said. "If you want to move to, say, baked chips, and if you can meet some calorie limits and sodium limits, that would be an option," Olson said. "We're not saying ban everything except for fruits and vegetables."

When students no longer have unhealthy snacks at their disposal, they often switch to traditional school lunches, Olson said. Schools often gain maximum financial benefits from those lunches, either from federal subsidies or the fact that they don't have to split the profits with snack vendors. This contradicts the fears of many school leaders that their districts will lose money if they drop popular snacks, he said.

The Minneapolis school district phased out a la carte snacks in its high schools five years ago. The district was losing money because staffing costs exceeded profits from the low-cost snacks that students could afford, explained Bertrand Weber, the district's nutritional services director.

Now the district is exploring a return of snacks -- but this time items such as pitas and hummus and yogurt parfaits, he said.

"We can strike, maybe, a good balance. I don't think we need to offer chocolate chip cookies and chips on a regular basis."

The Pew report shows that progress on school nutrition has ebbed. The rate of schools selling chocolate candy in Minnesota dropped from 76.5 percent in 2002 to 35 percent in 2008, but then increased to 39.1 percent in 2010.

Olson couldn't say whether the recession caused the trend, which happened nationally as well.

Minnesota's efforts to improve school nutrition were boosted in 2008 with $47 million in statewide health improvement grants that were issued in 2010 and 2011.

Portions of the money funded healthy snack options and farm-to-school meal programs in schools. At Staples-Motley High School, for example, students taking agricultural classes grew vegetables that were then used in school meals.

State budget cuts resulted in a reduction in grants, though, to only $11.3 million for 2012 and 2013.

Jeremy Olson • 612-673-7744