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.