Dr. Mitchell's research aims to explain variations in childhood growth patterns that are related to the causes and prevention of diseases in later life. This includes the study of behaviors and genes and their impact on body composition during development, with an emphasis on childhood sleep and physical activity behavior.
- He leads the Sleep and Growth Study that is designed to better understand how sleep patterns impact adolescent body composition, and to identify genetic and environmental determinants of sleep.
- He was the first to report that low frequency variation near the EN1 locus was associated with pediatric bone density.
- He led a gene-environment interaction study and observed that physical activity was associated with higher pediatric bone density, even among children genetically predisposed to bone fragility.