Researchers analyzed data from 10,588 children and adolescents across 21 sites between 2016 and 2022. The participants were part of the Adolescent Brain Cognitive Development Study, funded by the National Institutes of Health. The research team included scientists from Children's Hospital of Philadelphia, the University of Pennsylvania, the University of California at Berkeley, and Columbia University.
At age 12, children who owned smartphones had 30 percent higher odds of depression, 40 percent higher odds of obesity, and 60 percent higher odds of insufficient sleep compared to those without smartphones. The study defined insufficient sleep as less than nine hours per day.
The data showed 64 percent of participants owned smartphones at age 12. The median age for receiving a first smartphone was 11 years. At age 14, smartphone ownership had reached 89 percent.
Researchers found that the age when children first received smartphones mattered. For each year younger a child was when receiving their first smartphone, the risk of obesity and insufficient sleep at age 12 increased by approximately 8 to 9 percent. This pattern held even for children as young as age 4.
The study included a separate analysis of 3,486 children who did not own smartphones at age 12. Among these children, 1,546 acquired smartphones within the following year while 1,940 did not. At age 13, those who had acquired smartphones had 57 percent higher odds of clinical-level mental health problems and 50 percent higher odds of insufficient sleep compared to those who remained without smartphones. These results accounted for baseline mental health and sleep measures at age 12.
The researchers controlled for multiple factors including age, sex, income, parental education, race, and ethnicity. They also adjusted for ownership of other devices such as tablets, pubertal development, and parental monitoring. Results remained consistent across several different analytical approaches.
Dr. Ran Barzilay, the study's lead author and a child and adolescent psychiatrist at Children's Hospital of Philadelphia, noted the research examined only whether owning a smartphone was associated with health outcomes. The study did not investigate what children were "doing on their smartphones".
The researchers accounted for children's use of other technological devices including tablets and iPads. These adjustments did not change the findings.
The study could not determine whether smartphones directly caused these health problems. Previous research has found that excessive smartphone use correlates with reduced in-person social interactions, less physical activity, and decreased sleep, all of which can affect adolescent health.
Barzilay stated the findings showed health impacts even when smartphone use was not considered problematic. He emphasized that smartphones can serve beneficial purposes by strengthening social connections and supporting learning. Some families consider smartphones necessary for their children's safety.
Children between ages 8 and 12 average slightly over five hours of screen time per day, according to data cited in the study.
The researchers called for additional studies to identify which specific aspects of smartphone ownership and use connect to negative health outcomes. They plan to examine younger children who received smartphones before age 10 to understand who faces the greatest vulnerability to harmful effects and who might benefit most from smartphone access.
The study authors recommended that parents, children, and pediatricians engage in careful discussions before children receive smartphones. Barzilay suggested parents can implement rules such as prohibiting phone use in bedrooms at night and ensuring children participate in activities that do not require phones. He advised parents to monitor phone content and prevent smartphones from disrupting sleep.
The researchers noted their findings should inform both family decisions about smartphone use and potential public policy aimed at protecting youth health. They emphasized that some children who do not own smartphones may face various adverse consequences and challenges, highlighting the need to support families navigating this decision.
Notes: This post was drafted with the assistance of AI tools and reviewed, edited, and published by humans. Image: DIW-Aigen.
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by Asim BN via Digital Information World
