Smartphone Ownership in Young Adolescence Drives Physical and Emotional Health Risks

In a large national cohort of early adolescents, smartphone ownership at age 12 was associated with higher odds of depression, obesity, and insufficient sleep, according to a study published December 1 in Pediatrics. The analysis, based on 10,588 participants in the Adolescent Brain Cognitive Development (ABCD) Study, also found that acquiring a smartphone at a younger age was linked to obesity and insufficient sleep.

Researchers, led by Randy P Auerbach, PhD, Irving Phillips professor of child psychiatry in the department of psychiatry at Columbnia University, Vagelos College of Physicians and Surgeons, reported that at age 12, smartphone ownership (n = 6,739) vs not owning a smartphone (n = 3,849) was associated with a 30% increased risk for depression (odds ratio [OR] 1.31; 95% CI, 1.05–1.63), a 40% greater risk of obesity (OR 1.40; 95% CI, 1.20–1.63), and a more than 60% increased risk of getting insufficient sleep (OR 1.62; 95% CI, 1.46–1.79). Younger age at getting a smartphone increased certain health risks. For each earlier year of acquisition, the odds of obesity (OR 1.09; 95% CI, 1.02–1.16) and insufficient sleep (OR 1.08; 95% CI, 1.02–1.12) were higher.

The research team evaluated the associations using mixed-effects logistic regression models that were adjusted for demographic and socioeconomic factors, ownership of other digital devices, pubertal development, and parental monitoring. Caregivers reported both ownership status and age of first smartphone acquisition.

Auerbach and colleagues emphasized the persistently growing concerns about the potential health implications of early smartphone use. Their hypothesis was that smartphone ownership, particularly at younger ages, would be associated with worse mental and physical health outcomes during a developmental period already characterized by increased vulnerability to psychiatric disorders and sleep disturbances.

Findings at Age 13

In a secondary analysis, the investigators evaluated outcomes at age 13 among 3,486 youth who did not own a smartphone at age 12. They found that acquisition of a smartphone between ages 12 and 13 (n = 1,546) increased the odds of clinical-level psychopathology by nearly 60% (OR 1.57; 95% CI, 1.12–2.20) and insufficient sleep by 50% (OR 1.50; 95% CI, 1.26–1.77) vs not acquiring a device. These models controlled for baseline mental health and sleep. Results were consistent across sensitivity analyses.

The authors concluded that smartphone ownership was associated with depression, obesity, and insufficient sleep in early adolescence. They wrote, “We highlight the need for further research to better understand the adverse effects of smartphone ownership during the transition from childhood to adolescence, a developmental period that is already high-risk for psychiatric disorders and sleep problems.” They added that the findings may help inform caregivers and contribute to discussions around public policies intended to protect youth.