Introduction: Given the rising popularity of TikTok among adolescents, this study examines the impact of social media usage time on psychological variables such as social media addiction, body perception, and functional body appreciation, also considering gender differences.


Objective: Analyze the relationship between social media usage time, social media addiction, TikTok addiction, and functional body appreciation in Mexican adolescents, and we also compare these variables between gender groups in order to identify differences in usage patterns and body experience.


Methods: A correlational and comparative design was applied to a sample of 130 students aged 12 to 15 years from Northern Mexico. Using validated psychometric instruments (TTAS, ARS-10, FAS, and Silhouette Test), the data was analyzed using Pearson correlations and Student's t-tests.


Results: The time of use was positively associated with general addiction (r = .303, p < .001) and negatively associated with functional body appreciation (r = -.277, p = .001). Furthermore, addiction to TikTok revealed a positive relationship with functional appreciation (r = .458, p < .001). Women presented higher levels of addiction, conflict, and relapse, while men reported higher functional body appreciation. Conclusion: The intensive use of social media is linked to risks in mental health and teenage self-image. Nevertheless, TikTok also may promote expression and appreciation towards the functional body. This highlights the need for gender-focused interventions and awareness of the role of algorithms in future research.