Thinking about hitting the drive through to feed the kids tonight? You might want to think again. Those chicken nuggets and burgers might just be hurting your kids' test scores.

According to a new study published in the journal Clinical Pediatrics, the more often your child eats fast food, the more likely he will be to have poor grades in school. For the study, researchers from Ohio State University compared the fast-food consumption and grades of thousands of students from fifth through eighth grades. The more burgers and fries the students ate, the worse they did on the tests.

Researchers looked at questionnaires from 11,470 kids who reported how often they ate fast food. They found that the kids who ate fast food four to six times per week scored 20 percent lower on tests than kids who said they never ate fast food. 

The study found a link, but not a cause. In other words, just because the kids who ate more fast food also had lower test scores does not mean that it was the fast food that caused the poorer grades. Still, even after the researchers controlled for factors such as socioeconomic status, family background, and daily exercise, the link between the two remained.

"There's a lot of evidence that fast-food consumption is linked to childhood obesity, but the problems don't end there,” lead author Katy Purtell, an assistant professor of human sciences at Ohio State University, told Medical News Today. “Relying too much on fast food could hurt how well children do in the classroom. We're not saying that parents should never feed their children fast food, but these results suggest fast-food consumption should be limited as much as possible."

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