Smartphone Use at Age 12 Linked to Increased Eating Disorder Symptoms

A new study published in JAMA Network Open suggests a concerning link between smartphone ownership at age 12 and a higher prevalence of eating disorder symptoms by age 14. The research, which analyzed data from the large-scale American ABCD study, involved 8,957 participants. It divided them into two groups: 6,225 children who owned a smartphone at age 12 (approximately 70% of the sample) and 2,732 who did not.

The study examined four types of symptoms at ages 12 and 14: binge eating, compensatory behaviors to prevent weight gain, fear of weight gain, and linking self-worth to body weight. While not diagnosing specific eating disorders, the researchers looked for symptoms that could indicate distress and risk. By age 14, nearly a quarter of those who had smartphones at 12 reported at least one symptom, compared to 15.5% of those without.

Even after accounting for various factors such as gender, household income, parental education, body mass index, pubertal development, depression, ADHD symptoms, parental supervision, and other digital device ownership, smartphone ownership at age 12 was associated with a 49% increased risk of reporting at least one symptom by age 14. Specifically, it was linked to a 67% higher risk of binge eating and a 50% higher risk of compensatory behaviors. The risk of linking self-worth to body weight was nearly doubled, though no significant link was found with fear of weight gain.

Researchers, including lead author Dr. Jason Nagata from the University of California, San Francisco, suggest that smartphones expose young people to a vast amount of content focused on appearance, often curated with filters and AI. Shira Tirosh, director of the Eating Disorders Clinic at Maccabi Healthcare Services in Be'er Sheva, highlighted that personal smartphones offer unsupervised access to this content, unlike shared family devices. This exposure occurs during a sensitive developmental period, potentially exacerbating body dissatisfaction and the risk of disordered eating, especially with algorithmic content delivery on platforms like TikTok.

In Israel, the issue is compounded as smartphones are often given to children much younger than 12, sometimes as early as kindergarten, for reasons of safety and communication. Tirosh notes that children at these young ages often lack the critical thinking skills to discern advertising or understand the impact of the content they consume. The study, being observational, cannot definitively prove causation, as other family or individual factors might be involved. However, the consistent correlation, even after statistical adjustments, warrants further investigation into the specific mechanisms, such as social media content, algorithms, sleep disruption, or unsupervised access.