Adolescents who owned smartphones at age 12 were more likely to report several eating disorder symptoms, with some associations persisting two years later.
Study: Smartphone Ownership and Eating Disorder Symptoms in Early Adolescence. Image credit: RossHelen/Shutterstock.com
A recent JAMA Network Open study examined the association between smartphone ownership at age 12 and the prevalence of eating disorder (ED) symptoms in early adolescence.
Digital influences and adolescent eating behaviors
Eating disorders (EDs) affect millions of adolescents worldwide, but diagnosed conditions represent only part of the problem. In the US, an estimated 3.4% to 3.8% of female-identified adolescents and 1.2% to 1.5% of male-identified adolescents are affected by EDs, while more than one in five young people globally experience some form of disordered eating. These symptoms can interfere with daily life and may worsen over time.
At the same time, smartphones have become an almost unavoidable part of adolescence. Around 95% of US adolescents now have access to one, raising questions about how increasingly early access to digital environments could shape young people’s health. Previous research has linked smartphone ownership at age 12 with depression, obesity, and insufficient sleep, while greater exposure to social media, texting, and other screen-based activities has been associated with eating disorder symptoms.
The timing may be particularly important. Between the ages of 10 and 14, young people are navigating puberty while becoming more sensitive to peer approval and social comparison, even as their self-regulation continues to develop. Many also receive their first personal smartphone during these years, potentially giving them more private and frequent access to appearance-focused social media, idealized body images, and online communities that promote disordered eating.
Smartphone use can also influence eating behaviors in other ways. Nighttime use may disrupt sleep, which has been linked to changes in appetite regulation and emotional reactivity, while stressful digital experiences may encourage unhealthy coping behaviors. Personal smartphones can also provide unsupervised, individualized access to online content at an age when young people may be particularly susceptible to these influences.
Yet despite growing evidence linking early smartphone ownership with poorer mental health, sleep, and other health outcomes, its relationship with eating disorder symptoms has received relatively little attention.
Assessing the impact of early smartphone ownership on eating disorders
This cross-sectional and longitudinal analysis examined the association between early smartphone ownership and eating disorder symptoms among US adolescents using data from the ABCD Study, which included data collected from participants aged 10 to 17. The present analysis specifically focused on smartphone ownership at age 12 and ED symptoms at ages 12 and 14. Parent or caregiver reports from the ABCD Screen Time Survey (years 2 to 4) determined smartphone ownership status at age 12. Participants with missing ownership data were excluded.
Eating disorder symptoms at ages 12 and 14 were evaluated using the Kiddie Schedule for Affective Disorders and Schizophrenia, based on adolescent reports of binge eating, compensatory behaviors, weight gain concerns, and self-worth related to weight.
Covariates included sex, race, ethnicity, household income, parental education, study site, attention-deficit/hyperactivity and depressive symptoms, pubertal status, parental monitoring, body weight, and ownership of other digital devices. Interaction between sex and smartphone ownership was also examined. Generalized linear models with a Poisson distribution and log link assessed both cross-sectional associations at age 12 and longitudinal associations between smartphone ownership at age 12 and eating disorder symptoms at age 14. The longitudinal models additionally adjusted for ED symptoms at age 12.
Early smartphone ownership is linked to higher ED symptom risk in adolescents
This study analyzed 8,957 adolescents: 48% were female, 14% Black, 70% White, and 24% Hispanic. By age 12, nearly 70% owned a smartphone. These owners were more likely to be female, Black, or Hispanic; come from lower-income households; have parents with less education; be at a more advanced stage of puberty; and own other digital devices. Nonowners were more likely to own iPods, while tablet ownership did not differ significantly between the groups.
At age 12, binge eating was the most common ED symptom (8.2%), while worry about weight gain was rare (1.8%). Among smartphone owners, 9.2% reported binge eating at age 12, and by age 14, almost a quarter (24.2%) had at least one ED symptom.
Smartphone owners consistently showed higher rates of all ED symptoms than nonowners at both ages, although not all associations remained statistically significant in adjusted analyses. Those excluded from the study were more likely to be from racial minority groups and lower socioeconomic backgrounds.
In adjusted analyses, the association between smartphone ownership and worry about weight gain differed by sex, with a significant cross-sectional association among girls but not boys. In cross-sectional analyses, owning a smartphone at age 12 was associated with higher rates of binge eating (prevalence ratio 1.61), tying self-worth to weight (prevalence ratio 2.21), and any ED symptom (prevalence ratio 1.36).
Longitudinal analysis revealed that smartphone ownership at age 12 was associated with a greater risk of binge eating (risk ratio 1.67), inappropriate compensatory behaviors (risk ratio 1.50), tying self-worth to weight (risk ratio 2.03), and any ED symptom (risk ratio 1.49) by age 14. These findings suggest that smartphone ownership during early adolescence may be a potentially modifiable correlate of ED risk, although the study cannot establish that smartphone ownership causes these symptoms.
Conclusions
The current study found that smartphone ownership at age 12 was associated with a higher likelihood of reporting several eating disorder symptoms at age 14. The findings emphasize the need for increased awareness among parents, educators, and healthcare professionals regarding the potential mental health impacts of early smartphone use. The authors suggest that parents and caregivers may benefit from guidance on smartphone ownership, including age-appropriate limits and supervision of early device access, while further evidence is needed to inform broader recommendations.
The current study has several limitations, including reliance on self-reported symptoms, which may introduce reporting bias, and an observational design that precludes establishing causality. Unmeasured confounding factors, such as psychosocial influences or differences in device-use patterns, may also affect the results. Reverse causation cannot be ruled out, and the exclusion of participants with missing data may introduce sampling bias and limit the generalizability of the findings to some racial, ethnic, and lower socioeconomic groups. ED symptoms were also measured as yes-or-no outcomes, limiting the ability to capture differences in symptom severity.
Future research should clarify the mechanisms underlying the association between smartphone ownership and eating disorder symptoms, including the potential roles of social media exposure, sleep disruption, and body image-related processes. Larger studies should also examine whether transitions in smartphone ownership are associated with subsequent changes in ED symptoms, particularly among adolescents who newly acquire smartphones.