PROJECT SUMMARY The quality of children’s diet has deteriorated tremendously over the last decades in the U.S. and other developed countries, with increased intake of unhealthy foods and decreased consumption of healthy foods. The effects of children’s diet on obesity and chronic disease have been well-studied, but recent evidence suggests that children’s diet also affects their behavioral, emotional, and academic functioning. However, little is known about the neural substrates that may underlie these effects. Studies with animal models convincingly demonstrate that ‘Western’ diet – high in saturated fat and added sugars – has a profound negative effects on cognition and behavior through impairments in frontal, limbic, and hippocampal areas of the brain. However, few studies have examined connections between diet and the brain in humans. The relationships between diet, behavior, and academic outcomes are particularly relevant in early adolescence when diet quality typically deteriorates; behavioral, emotional, and academic problems increase; and the brain undergoes rapid development and reorganization that make it more vulnerable to environmental influences. Because virtually nothing is known about the impact of diet on the adolescent brain, this R21 application aims to examine associations between adolescents’ diet and white matter microstructure, neurochemistry, and brain function on tasks related to 1) sustained attention, 2) learning and memory, and 3) emotional and behavioral regulation. We leverage longitudinal, multi-source data collected through the ongoing Adolescent Diet Study, which conducts a full week of daily 24-hour diet recalls and lunch observations on 288 middle school students annually in 6th, 7th, and 8th grade. This R21 project would add a single neuroimaging session, IQ screen, and nutrition biomarkers for a random subset of 80 participants after the 8th grade assessment. Integrated data from both studies will allow us to determine the relationships of intake of saturated fats and added sugars with key aspects of the adolescent brain that underlie behavioral, emotional, and academic functioning – white matter microstructure, neurochemistry, and brain function on tasks of attention, verbal memory, and emotional and behavioral regulation. Better understanding of the connections between diet and the adolescent brain will facilitate more effective public health messaging and nutrition-focused interventions to enhance healthy brain development and improve emotional, behavioral, and academic outcomes of youth.

PROJECT NARRATIVE Dietary factors have been implicated in adolescents’ behavioral, emotional, and academic functioning, but the underlying neural mechanisms are not well understood. This project will examine associations between adolescents’ diet and neural structure and chemistry, as well as brain function during tasks focused on attention, verbal memory, and emotional and behavioral regulation. The findings will inform intervention programs and policies to optimize healthy adolescent brain development.