Relationships between Dietary Intake and Cognitive Function in Healthy Korean Children and Adolescents

BACKGROUND: It has long been theorized that a relatively robust dietary intake impacts cognitive function. The aim of the study was to explore dietary intake and cognitive function in healthy Korean children and adolescents. METHODS: Three hundred and seventeen healthy children with no previous diagnosis of neurologic or psychiatric disorders were evaluated (167 girls and 150 boys with a mean age of 11.8 ± 3.3 years). Analysis indicators including food frequency questionnaires (FFQs) consisting of 76 items and neurocognitive tests including symbol digit modalities (SDMT), verbal memory, visual memory, shift attention, reasoning, and digit span (forward and backward) tests were observed and recorded. RESULTS: The standard deviation in reaction time was significantly shorter in girls than in boys (p < 0.05). Verbal memory and SDMT percentile results were significantly higher in girls than in boys (p < 0.05). Vitamin C and potassium intake showed positive correlation with SDMT results (p < 0.05). Vitamin B1 intake showed positive correlation with the results of digit span forward tasks and SDMT (p < 0.01). Vitamin B6 intake showed positive correlation with the results of digit span forward tasks (p < 0.01). The consumption of noodles showed negative correlation with verbal memory, SDMT, shift attention, and reasoning test results (p < 0.05). The consumption of fast food showed negative correlation with SDMT and reasoning test results (p < 0.05). The consumption of Coca-Cola showed negative correlation with the results of verbal memory tests (p < 0.05). The consumption of mushrooms showed positive correlation with visual memory and reasoning test results (p < 0.05). The consumption of nuts showed positive correlation with SDMT results (p < 0.01). Omission errors were negatively correlated with the intake of protein, vitamin B1, vitamin B2, niacin, and vitamin B6 (p < 0.05), as well as with vitamin D and zinc intake (p < 0.01). Reaction time showed positive correlation with caffeine intake (p < 0.05). Omission errors were positively correlated with the consumption of rice and ramyeon (p < 0.01). Reaction time showed positive correlation with the consumption of snacks (p < 0.05). Standard deviations in reaction times showed positive correlation with the consumption of rice (p < 0.01), snacks, and chocolate (p < 0.05). Omission errors were negatively correlated with the consumption of rice with mixed grains (p < 0.01) and eggs (p < 0.05). CONCLUSION: The relationship between dietary intake and cognitive function is generally better observed in girls than in boys. The consumption of healthy foods is correlated with good cognitive function. These results suggest that diet is closely related to cognitive function, even in healthy children and adolescents.