A new study published in JAMA Pediatrics on May 18, 2026, reveals that 52.1% of American teens aged 15 are losing critical sleep because of late‑night phone use. Researchers from the University of California and Mount Sinai School of Medicine, led by Dr. Jason Nagata, tracked 657 adolescents using an app that monitored their phone activity.
Sleep disruption: Teens averaged 50 minutes of phone use between 10 PM and 6 AM on school nights.
Brain development: Missing the recommended 8–10 hours of sleep hinders both brain and body growth.
Academic impact: Poor sleep is linked to weaker learning and lower school performance.
Social media use: Platforms like TikTok, Instagram, YouTube, and Netflix dominate late‑night activity.
Researchers urge families to set clear house rules: Establish cut‑off times for phone use. Keep phones out of bedrooms at night and encourage healthier routines that prioritize rest.
Sleep is not just rest , it’s the foundation for cognitive growth, emotional regulation, and physical health. Disrupted sleep during adolescence can have long‑term consequences, from academic struggles to developmental delays.