Much of the scientific literature on the effects of digital screen media use on child well-being focuses on the wide-ranging psychological, cognitive, and social effects. More recently, there has been growing evidence of the role of digital screen media use in physical health. This section on physical health includes five chapters exploring distinct dimensions of physical health, including physical activity, nutrition, food marketing, marketing of other health risk behaviors, sleep health, physical injuries, and ocular health. Each chapter describes the current state of the evidence, gaps and limitations in the literature, and directions for future research about the pervasive role of screens in the lives of children and the implications (potentially both positive and negative) for physical health. A consistent limitation across all the chapters includes challenges with measurement and assessing causality. Finally, each chapter concludes with recommendations aimed at mitigating the effects of digital screen media use on the range of physical health outcomes addressed.