Haidt explores the significant negative impacts of a phone-based childhood. He identifies four primary harms: social deprivation, sleep deprivation, attention fragmentation, and addiction.

Social Deprivation

Smartphones have drastically reduced face-to-face interactions among adolescents. Before smartphones, children played together and engaged in real-world social activities, essential for developing social skills. The introduction of smartphones has led to a sharp decline in time spent with friends, as teens now interact primarily through social media and online platforms. This shift has resulted in increased feelings of loneliness and isolation. Haidt emphasizes that physical presence and direct interactions are crucial for mental health, and the lack of these interactions contributes to higher rates of depression and anxiety.

Sleep Deprivation

The second harm Haidt addresses is sleep deprivation. The natural sleep patterns of adolescents shift during puberty, requiring them to sleep later and longer. However, the constant presence of smartphones and the temptation to stay connected disrupts their sleep. Studies show a significant increase in sleep problems since the widespread adoption of smartphones. Insufficient sleep affects cognitive function, memory, reaction times, and overall mental health, leading to poorer academic performance and increased risk of accidents and illnesses. Haidt underscores that sleep is vital for brain development, particularly during adolescence.