Everyone's familiar with the old adage that "breakfast is the most important meal of the day." It's such a widespread platitude that many take it as a simple truism, even though there are some studies that may suggest otherwise. But here's a study that scores one for team breakfast: Public health experts at Cardiff University have established a firm link between the consumption and quality of your breakfast and how well you attain knowledge taught in school, reports MedicalXpress.

The study looked at 5,000 9- to 11-year-olds who attended more than 100 different primary schools. It observed the students' breakfast habits and followed up on their later academic accomplishments. It was found that kids who ate breakfast regularly also tended to perform the best in their studies.

There is one caveat, however. Kids who ate low-quality breakfast, such as sweets or fried food, performed no better than kids who regularly skipped breakfast entirely. In other words, it's not just that you eat breakfast that's important, it's also what you eat.

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Healthy eating, according to the study, was mostly measured by portions of fruit and vegetables consumed. How these eating habits carried over into the rest of the day also had a correlative effect on school performance. So while eating a healthy breakfast mattered, so did eating a healthy lunch and dinner. Eating healthy was the key.

"While breakfast consumption has been consistently associated with general health outcomes and acute measures of concentration and cognitive function, evidence regarding links to concrete educational outcomes has until now been unclear, said Hannah Littlecott, lead author on the study. "This study therefore offers the strongest evidence yet of links between aspects of what pupils eat and how well they do at school, which has significant implications for education and public health policy."

In other words, this study could have a direct impact on debates about whether students should be provided food as part of their educational experience. It may also inform what kinds of foods might be dictated for students to consume. Many school lunch programs in the U.S. have been criticized for providing students with junk food, like pizza or French fries, which not only caters to bad habits but also reinforces them. But others have objected to policies that force kids to eat things that they don't want to eat, too.

This new study shows, however, that issues concerning dietary choice and academic performance cannot be so easily separated.

"This further emphasizes the need for schools to focus on the health and education of their pupils as complementary, rather than as competing priorities," added Chris Bonell, professor at the University College London Institute of Education.