Early smartphone ownership linked to increased risk of eating disorder symptoms in adolescents

A recent study suggests that children who get smartphones by age 12 are more likely to exhibit symptoms linked to eating disorders, raising concerns about the timing of device use and its impact on mental health.

A new study in JAMA Network Open adds to concerns that early smartphone ownership may coincide with poorer eating-related outcomes in adolescence. Researchers reported that US children who already had a smartphone at age 12 were more likely to describe symptoms linked to eating disorders at that age and again two years later than peers without a phone of their own.

The cohort study followed 8,957 adolescents from multiple sites and asked parents whether their child owned a personal phone, what type of device it was and when it was first received. Young people then completed interviews covering binge eating, fear of weight gain, compensatory behaviours such as vomiting or excessive exercise, and the degree to which self-worth was tied to body weight. According to the study, about 69.5% of participants owned a smartphone at age 12.

At age 12, smartphone owners had higher rates of binge eating, greater likelihood of linking self-worth to weight and a higher overall prevalence of any eating-disorder symptom. By age 14, early owners were also more likely to report binge eating, inappropriate attempts to avoid weight gain, a stronger connection between self-worth and weight and any eating-disorder symptom. The researchers did not find a significant overall link between smartphone ownership and worry about weight gain, although girls who had smartphones reported more of those worries than boys at age 12.

The authors urged parents and caregivers to think carefully about when a child first gets a device and how much supervision comes with it. They wrote that families may benefit from guidance on age-appropriate limits and early access. The study, led by Jason M. Nagata of the University of California, San Francisco, was published online on September 25 and was funded by the National Institutes of Health. The authors reported no conflicts of interest.

The findings do not prove that smartphones cause eating-disorder symptoms. The researchers relied in part on self-reported symptoms, could not account for factors such as bullying or neurodevelopmental conditions and did not randomly assign phone ownership. Still, the results fit with earlier research suggesting that digital habits can shape body image and weight-related behaviour. Other studies in JAMA Network Open and JAMA Pediatrics have linked heavier smartphone or social media use with body dissatisfaction, unhealthy weight-loss attempts, weight concerns and dieting, while a separate JAMA study found very high daily screen time among US adolescents and associations with poorer health and school outcomes.