In a letter to Agriculture Secretary Tom Vilsack earlier in May, 40 Republicans and Democrats in Congress questioned his department’s proposal to reduce the amount of potatoes in school meals to about two servings a week, saying they can be a tasty, healthy way to provide potassium, fiber and other nutrients at a low cost.

“It’s a great vegetable and I don’t know why we are picking on the potato,” said Rep. Jean Schmidt (R-Ohio) who signed the letter. “I think this is very much an overreach.”

It’s a refrain some in Congress are using more frequently to describe the Obama administration’s efforts to get kids to eat healthier foods—the government shouldn’t be telling kids what to eat. Should it be up to USDA to decide that potatoes can’t be eaten responsibly?

Since the guidelines apply to federally subsidized meals, schools are generally fine with broad federal guidelines on nutrition—how many servings a week children are allowed of grains or vegetables, for example. But many schools have balked at attempts to tell them exactly what foods they can’t serve.

“I feel that guidance is helpful, but that micromanagement is not,” says Doug Davis, food service director for Burlington, Vt., schools. “Having standards is important, but limiting foods by category is really challenging.”

Davis says he has worked hard over the past few years to source more foods locally and forgo processed foods. The potato grows well in his part of Vermont—so well that children in his school district are growing their own to eat off the lunch line. His lunchroom features all sorts of healthy potato dishes, including a baked potato bar.

Health advocates say schools need to help strike a balance in what kids eat and that is exactly why potatoes should be restricted. Because children eat so many potatoes already, schools should focus on providing more variety.

“Kids are not eating enough vegetables and when they do eat vegetables they are eating potatoes way too often,” says Margo Wootan, director of nutrition policy at the advocacy group Center for Science in the Public Interest, which pushed for the standards. “Too much of anything, even a good food, isn’t healthy because people need to eat a variety of foods.”

The Institute of Medicine and other experts advised the U.S. Department of Agriculture that parents already do a great job of serving potatoes to their kids at home so they don’t need to eat as many potatoes at school, and the USDA issued improved nutritional guidelines in January about the variety of vegetables children currently eat, such as carrots, tomatoes and leafy greens.