Currently, school lunches are generally designed according to the guidelines put out by the USDA National School Lunch Program (NSLP). More than half of US children participate daily, which translates to approximately 28 million lunches distributed per day. The nutritional guidelines for the NSLP lunches are based on "Dietary Recommendations for Americans" composed by the Institute of Medicine. Its requirements are that a school lunch includes one third of the RDA of calories, vitamins A and C, calcium and iron, and protein. Additionally, the lunch should contain no more than 30% of the total calories from fat, and no more than 10% from saturated fat. The guidelines provide unclear recommendations on fruit, vegetable, whole grain, and sodium content. In general, the guidelines leave room for interpretation and do not always lead to the creation of healthy meals. For example, in several schools pizza counts as a vegetable due to its tomato sauce.