The one nutrient that science says can help your child perform better in school

It's been found to boost cognitive ability and test scores.

It turns out there is one more reason to get your kids to eat more vegetables. In addition to being part of a healthy diet, they can also help them out in the classroom this school year.

According to two new studies from the Center for Nutrition, Learning and Memory at the University of Illinois, the nutrient lutein—found in many fruits and veggies—can positively affect your child's test scores and grades.

Kids can get their lutein fix by eating certain foods, says Matthew Kuchan, Ph.D., an author on both studies. While the plant pigment is mostly known for protecting eyes from vision loss, the nutrient has been found to benefit brain health.

The first study published in the journal Nutritional Neuroscience found that 8- and 9-year-old children with higher levels of lutein in their bodies achieved higher test scores–especially in math and writing. The other study published in the International Journal of Psychophysiology showed that children had increased cognitive ability and were able to complete tasks more efficiently.

According to Dr. Kuchan, the best way to increase your child's lutein levels is to incorporate leafy greens, like spinach and kale, and "colorful" fruits and vegetables like broccoli, zucchini, corn and carrots. Even egg yolks contain high amounts of the nutrient. "All are great sources of lutein and can be easily transformed into kid-friendly recipes—for at home or at school," says Dr. Kuchan.

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There isn't an exact recommendation for how much lutein-containing foods children should be eating, but Dr. Kuchan says parents should be following the United States Department of Agriculture guidelines for fruit and vegetable servings.

In addition to lutein, research has shown that vitamin E also improves brain health. "Naturally found in parts of the brain that are linked to memory, vision and language development, natural vitamin E is a powerful antioxidant that has been shown to work as a complement to lutein," explains Dr. Kuchan. Accoring to the Harvard University School of Public Health, you can find vitamin E in foods like almonds and sunflower seeds.

So don't hesitate to dish out extra servings of fruits and vegetables at the dinner table. They might pay off in more ways than one.