Many school cafeterias adopt debit account payment systems as quick, convenient ways to keep lunch lines moving, but according to this study conducted by Cornell University’s Food and Brand Lab researchers, putting it on the debit account may impact the health of kids’ meals. Schools use debit systems without the option of paying with cash, students’ lunches contained fewer fruits and vegetables, more unhealthy items, and more calories overall.

Researchers David Just, PhD and Brian Wansink, PhD examined the lunch purchases of 2,314 students in grades 1 through 12 to see how payment methods impacted food choice. In schools that completely converted to debit systems—as opposed to those that gave students the option to pay with cash instead—fruit purchases were 13% lower, while vegetable purchases were 20% lower. Students at debit-only schools were also more likely to purchase less healthy food options, such as candy, dessert, and fried foods. In fact, the lunches of students at debit-only schools contained 63 more calories from these less healthy foods and 32 fewer calories from healthier options.

According to Just and Wansink, the degree of parental guidance at lunchtime may be partly responsible for this phenomenon. When parents give children a certain amount of cash for lunch each day, they can monitor their kids’ daily expenditure more closely, resulting in better lunch choices. Debit systems, however, eliminate the restrictions of a daily cash allowance, providing kids the opportunity to spend their lunch money as they please—with unhealthy consequences. A debit system which allows parents to set daily limits or food-specific restrictions may be an ideal compromise between convenience and guidance. Alternative methods—like the implementation of a “cash for cookies” rule— can nudge kids towards healthier foods by making them pause before impulse-purchasing less healthy options.

Link to Study