Screen time and social media use are ubiquitous among adolescents (Nagata et al., 2021a), with a significant increase in use during the COVID-19 pandemic (Nagata et al., 2021b). For many adolescents, screen time and social media use are mechanisms of entertainment and social connection, which ultimately creates avenues for psychological, emotional, and social impacts (Chassiakos et al., 2016; Lissak, 2018). For example, research has shown that higher levels of screen time and social media use (i.e., hours) (Przybylski et al., 2020; Orben and Przybylski, 2019), correlate with depression, anxiety, physical inactivity, higher body mass index (BMI), poor body image, and eating disorders (Lissak, 2018; Nagata et al., 2021c; Nagata et al., 2021d; Harriger et al., 2022; Derenne and Beresin, 2018). The latter of which, poor body image and eating disorders, have recently gained significant media attention (Woo, 2021; Wells et al., 2021).

Indeed, recent research has underscored the relationship between screen time and social media use and poor body image, often via mechanisms of comparing appearances, among younger individuals, such as adolescents (Saiphoo and Vahedi, 2019; Fardouly and Vartanian, 2016). Additionally, social media algorithms may play an important role in body dissatisfaction, whereby users see more of the content that they engage with, either actively via following specific accounts or “liking” content, or passively via spending longer time on photos/videos. This creates a “rabbit hole” for users, which ultimately perpetuates unrealistic body ideals and further propels attempts to change one's body (Harriger et al., 2022). This may be particularly problematic for adolescents given the appearance-based changes that accompany puberty (Rapee et al., 2019), which may increase body dissatisfaction and attempts to change one's body. Furthermore, adolescent health and wellbeing are particularly influenced by social domains (Patton et al., 2016).

While much of the focus on the impacts of screen time and social media use have focused on efforts to lose weight, such as dieting (Derenne and Beresin, 2018; Fardouly and Vartanian, 2016; Padín et al., 2021), less is known about how these factors are associated with weight gain attempts, which is more common and understudied among boys (Solmi et al., 2020). The relationships between screen time and social media use and efforts to alter one's body, either weight loss or weight gain attempts, are likely driven by similar mechanisms. Specifically, viewing culturally ideal body types, one that is thin, toned, and curvy for girls (Kelley et al., 2010) and muscular and lean for boys (Murray et al., 2017), can lead to the internalization of such ideals and increase body dissatisfaction, thus catalyzing behavioral attempts to achieve such ideals (Tylka, 2021; Ata et al., 2015). This process may be particularly important given that both screen time, social media use (Nagata et al., 2021b), and eating disorders (Taquet et al., 2021; Linardon et al., 2022) have increased among adolescents during the COVID-19 pandemic. Additionally, much of the literature on the relationship between screen time and social media use and weight-change behaviors is focused on regional samples (Padín et al., 2021) from high-income, western, English-speaking countries, which neglects the global pervasiveness of screen time and social media use (World Health Organization, 2020). Furthermore, while body ideals have evolved over time, and there is some homogeneity in body ideals cross-culturally, many of the dominant ideals (i.e., thin and toned for girls and muscular and lean for boys) are more prevalent in high-income, English-speaking contexts (Nagata et al., 2020a; Swami, 2015; Reel et al., 2015).

To address the gaps in the literature, this study aimed to determine the association between hours of weekday screen time and social media use and weight-change behaviors, including weight loss and weight gain attempts, and dieting to lose weight, among an international sample of adolescents from Australia, Canada, Chile, Mexico, the United Kingdom, and the United States. These countries were selected given they represent four diverse, high-income, predominately English-speaking countries (Australia, Canada, United Kingdom, United States), as well as two middle-income, non-English-speaking countries (Chile, Mexico), which may elucidate international trends. Findings will provide important knowledge regarding the global connection between screen time and social media use on weight-change behaviors, with a specific advancement of knowledge by including participants in middle-income, non-English speaking countries (i.e., Mexico and Chile).