Association Between Physical Activity and Breakfast Skipping Among Saudi Adolescents: A Multi-City Analysis of the 2019 Global School-Based Student Health Survey

Background: Physical activity and breakfast consumption are commonly clustered adolescent health behaviors, but Saudi evidence on their association is limited to a single city, and whether this relationship varies by sex or age remains untested. Objective: We aimed to examine the association between physical activity frequency and breakfast skipping among Saudi adolescents and determine whether it differs by sex and age. Methods: This cross-sectional study used 2019 Global School-based Student Health Survey (GSHS) data from adolescents in five Saudi cities (Riyadh, Jeddah, Dammam, Khamis Mushait, Tabuk; N = 5900). Cases with missing data on any analysis variable were excluded listwise (final N = 5431). Physical activity frequency and breakfast skipping were both assessed using self-reported GSHS questionnaire items. Logistic regression via generalized estimating equations (clustered on school) estimated adjusted odds ratios, adjusting for sex, age (years), grade, nationality, and city; moderation by sex and age was tested with interaction terms and a joint Wald test, and robustness was assessed with three sensitivity analyses. Results: The final analytic sample (N = 5431) had a mean age of 13.71 years (standard deviation (SD) 1.13) and was 54.6% female. Breakfast-skipping prevalence was 18.7%. Each additional physically active day was associated with 10% lower odds of breakfast skipping (adjusted odds ratio [AOR] = 0.90, 95% confidence interval [CI] 0.86–0.93, p < 0.001), a finding robust across all sensitivity analyses, including multiple imputation (OR = 0.89, 95% CI 0.87–0.92). Female sex, non-Saudi nationality, older age, and city of residence (higher odds in Jeddah and Dammam relative to Riyadh) were independently associated with greater odds of skipping. Neither sex nor age moderated the physical activity–breakfast association (joint Wald χ2(2) = 2.70, p = 0.259). Conclusions: Physical activity frequency was independently and robustly associated with lower breakfast skipping among Saudi adolescents, irrespective of sex or age, extending single-city evidence to a larger and more diverse population. School-based strategies that jointly promote physical activity and breakfast consumption may not require tailoring by sex or age, although this study did not evaluate intervention effectiveness, and this inference should be confirmed prospectively; city-level variation suggests monitoring and resource allocation may benefit from geographic disaggregation.