Public health officials have long viewed improving kids' eating habits as one way to help nip the obesity epidemic in the bud. Nearly two-thirds of U.S. adults are overweight or obese, contributing to skyrocketing rates of diabetes and other diseases, according to the Centers for Disease Control. The problem is often rooted in childhood: About one in five American kids is overweight, roughly double the ratio of 30 years ago, according to The Obesity Society.
To curb unhealthy eating and childhood obesity, the government spends about $8 billion per year on the National School Lunch Program. Last year, it served meals daily to more than 30 million students, or about half the U.S. school-aged population. For many kids, especially in low-income families, these are the main meals of the day, and may help set consumption patterns for life.
Yet fewer than 20 percent of schools serve lunches that follow the government's Dietary Guidelines for Americans. Schools are required to provide one-third of the recommended dietary allowances of Vitamin C and other nutrients, and ensure that no more than 30 percent of a student's calories come from fat, and 10 percent from saturated fat. Twice as many schools met the saturated fat limit in 2004–2005 as during the late 1990s. But after that doubling, only one-third of schools achieved the standard.
"An awful lot of the foods served are low in nutrients and high in fat and calories. That's generally not a good thing," said Anne Gordon of Mathematica Policy Research, which conducts the School Nutrition Dietary Assessment, the government's main study of school meals.
Minnesota applied economics graduate student Barbara Wagner, a former Senate aide who now works for Montana's state government, set out to explain why the system doesn't work as intended. Conventional wisdom in the field has held that nutritious meals cost more than unhealthy ones (there is some evidence for that), and that students prefer to eat junk food instead of healthy meals.
"The answer given by a lot of policy groups is that in order to solve the problem of school foods, we should just give them more money," Wagner said. "That didn't make sense to me."
Advised by professors Benjamin Senauer and C. Ford Runge, Wagner examined data from 330 Minnesota public school districts, searching for relationships between factors such as lunchroom labor costs, student income levels and the nutritional value of meals. The results were published in the Winter 2007 issue of the Review of Agricultural Economics.
Wagner found that more nutritious meals — for example, those with less fat content — don't lead to decreased lunchroom sales. The analysis also shows that healthier lunches aren't necessarily more expensive. When school lunchrooms cook nutritious cuisine from scratch, they may pay higher salaries and training costs, but can make up savings by purchasing fresh foods instead of processed goods.
Although school meal administrators often hear complaints from students and parents when they swap out hamburgers for healthy meals, another University of Minnesota study, published in the December Journal of Consumer Affairs, showed that over the course of months, students will eat healthily if given the option.
Then-master's student Corbett Grainger, now a Ph.D. candidate at University of California-Santa Barbara, analyzed the two-year transition of a school district from cafeterias full of pizza and cheeseburgers toward service of freshly made salads, sandwiches and whole-grain organic cookies. Many unhealthy food choices were still available, but students at the schools, in the middle-class suburbs of Minneapolis, often opted for more nutritious items.
Wagner suggests a half-dozen policy ideas to take advantage of these conclusions, including one-time government subsidies to create the infrastructure and trained labor force to inexpensively cook nutritious school lunches. Such a system works in St. Paul, where thousands of students eat free or reduced-price meals, and workers at the school food service's central production facility bake whole-grain bread or make meat sauce from scratch.
Some school food directors question whether this could work nationwide without sacrificing nutrition or increasing the amount of money districts spend on cooking.
"People talk about whole grains and fresh fruits and vegetables, and we support that, but that costs money," said Katie Wilson, president-elect of the School Nutrition Association and nutrition director for a Wisconsin school district. "I don't know how they can say it doesn't cost any more to cook from scratch."
At Hopkins, prices did increase by about 50 cents per meal to serve healthier food. Yet Wagner's data shows little relationship between the meals' nutritious content and long-term, average costs of preparation within a district.
One Wagner proposal that many school food administrators support is an effort to control indirect costs, or fees paid by the food service back to the district. The cafeterias are supposed to be run like nonprofit businesses within the school: Any revenues above government subsidies are to be pumped back into the food operation. But districts charge their food services for costs such as lighting or rent, and at times, several food service directors said, school boards under financial pressure may increase those fees by unjustified amounts. Wagner's study shows that meals are less healthy when food service operations incur higher indirect costs, partly because they absorb funds that might upgrade kitchens.
"In these cash-strapped environments, you can understand why the districts would want to get more money. But the effect is that it's injurious to the nutritional quality of the food," Minnesota's Runge said.
Wagner suggests several other options for the U.S. Department of Agriculture, which operates the national lunch program, including a ban on indirect costs for school food services that don't meet nutrition guidelines. That might encourage school boards to invest in infrastructure to cook healthier food, hoping to yield greater revenue in the long run.
In general, Wagner argues, the USDA offers few carrots or sticks to push schools toward serving healthy food. Under the terms of the national program, schools that don't meet nutrition standards must develop a corrective action plan with their state, which has authority to take away subsidies. But states rarely cut funding, because it's perceived to be even more detrimental to the health of students. Although a 2004 law mandated that school districts create wellness policies, including on nutrition, there is little oversight to make sure written policies are implemented.
Thousands of American public schools are in dire financial straits, and nutrition may be far from the top of their priority list. Yet even small changes might have a big impact. Ann Cooper, director of nutrition services for the Berkeley (Calif.) Unified School District, said a limit on fried foods or high-fructose corn syrup could decrease unhealthy eating, without increasing costs.
Wagner's paper, the first to examine meal prices and buying patterns at hundreds of schools, shows the problem may not be as insurmountable as previously thought. "These are clear findings suggesting we could be doing a lot better," Runge said.