Problematic Internet use (PIU) is an increasingly prevalent public health concern among Chinese rural adolescents, yet little is known about its underlying socioeconomic determinants. Food insecurity (FI), another ongoing pressing issue in rural Chinese areas, refers to the uncertainty or inability to access nutritionally adequate food in socially acceptable ways, including emotional distress and physical discomfort. However, research examining the intersection of FI and PIU remains scarce. FI is likely to contribute to adolescents' PIU by exacerbating emotional distress. According to the compensatory Internet use theory, adolescents may turn to the Internet as a maladaptive coping strategy to escape FI-related stress. Moreover, empirical research is needed to explore the potential mechanisms within their association among rural Chinese adolescents, where structural and cultural factors may shape this relationship in unique ways. The present study investigated how FI was associated with PIU in rural Chinese adolescents, focusing on social support as a moderator and self-esteem as a mediator among 1654 students (55.44 % girls; M = 16.54 years) from under-resourced rural areas in China. To ensure robustness, we controlled for age, sex, socioeconomic status (SES), and body mass index (BMI). Correlation analyses showed that FI was positively associated with PIU, and social support was negatively associated with PIU. Moderation analyses showed that the association between FI and PIU was heightened in adolescents who reported receiving higher school support (β = 0.09, p = 0.025), family support (β = 0.10, p = 0.005), or peer support (β = 0.08, p = 0.020). Mediation analyses showed that the strengthened associations between FI and PIU due to more school support (B = 0.15) and more peer support (B = 0.07) might lower adolescents' self-esteem, which, in turn, predicted higher PIU, but not family support. The findings illuminate the multifaceted roles of social support and self-esteem in the association between FI and PIU, offering implications for future practice interventions. From a policy perspective, our study can guide resource allocation and intervention efforts in rural communities. age
