Oxidative Stress in Children and Adolescents: Insights Into Human Biology.

Oxidative stress (OS) is a key biological challenge and selective pressure for organisms with aerobic metabolism. The result of the imbalance between reactive oxygen species production and antioxidant defense, OS can damage proteins, lipids, and nucleic acids and plays an important role in driving variation in biological aging and health. Among humans, OS research has focused overwhelmingly on adults, with demonstrated connections between OS, inflammation, and metabolic and neurodegenerative conditions. Relatively little attention has been given to OS during childhood and adolescence. This lack of early life OS research exists despite clear implications for informing human life history evolution, subadult development, and lifelong health. Here, we review current knowledge on OS during human subadulthood. Our objectives are threefold: (1) To highlight common methods for measuring OS among children and adolescents and to establish typical measurement values; (2) To summarize the evidence linking demographic and ecological factors to variation in subadult OS; (3) To identify avenues for future OS research in human biology. Our review underscores an expanding methodological toolkit for assessing OS among children and adolescents. Subadult OS is considerably elevated compared to OS among adults, a pattern eliciting unknown consequences and likely related to increased early life metabolic demands (e.g., unique human brain development). Factors such as diet, physical activity, infectious disease, and structural neglect also appear to drive subadult OS. Current limitations for research on subadult OS are evident. Future work should emphasize evolutionary, biocultural, and energetic life course perspectives to advance this promising area of human biology.