Students who eat a federally funded school lunch are likelier to be overweight than those who don't, but those who also get a federally funded school breakfast are at lower risk. Those conclusions come from a study of 13,500 schoolchildren titled "School Nutrition Programs and the Incidence of Childhood Obesity," published in the summer issue of The Journal of Human Resources (subscription required).
The authors speculate that cost constraints and the use of surplus commodities make developing healthy and inviting school lunch dishes difficult, which may drive children to add on less healthful a la carte alternatives that districts have a financial incentive to sell. School breakfasts don't have the same effect because they more often consist of healthful components.
