Social Media Use, Body Shape Concern, and Self-Esteem Among Saudi Student Nurses: A Cross-Sectional Descriptive Study

Introduction: This cross-sectional study examined associations between Social Media Use (SMU), Body Shape Concern (BSC), and Self-Esteem (SE) among Saudi student nurses. We assessed demographic differences in these variables and tested whether SE moderated the SMU–BSC relationship. Methods: We conducted a cross-sectional correlational study with 324 student nurses recruited through convenience sampling at King Khalid University. Data were collected via Google Form between January and February 2025 using the SMU Questionnaire, BSQ-8A, and Rosenberg Self-Esteem Scale. Results: Higher SMU and greater BSC were each associated with lower self-esteem (ρ = −0.334 and −0.492, p < 0.001, shared variance = 11.2% and 24.2%). SMU and BSC were positively correlated (ρ = 0.393, p < 0.001). Female students reported marginally higher SMU and BSC than males, but effect sizes were negligible (Cohen’s d = 0.07 and 0.02). Second-year students scored highest across all three variables, with small effect sizes (η2 = 0.02–0.03). SE did not moderate the SMU–BSC relationship (interaction term: p = 0.113), though both SMU and SE independently predicted BSC. Conclusions: Among Saudi student nurses, higher social media use and greater body shape concern were associated with lower self-esteem. Female and second-year students showed marginally higher scores, though effects were small. Contrary to the vulnerability-stress hypothesis, self-esteem did not moderate the social media–body concern relationship. Interventions may need to combine media literacy with self-esteem enhancement rather than relying on self-esteem approaches alone.