The relationship between physical activity and depression, anxiety, and stress in college students: a mediating effect of diet

Jiazhi Sheng¹Caizia Chen^2*Lamei Gong¹Jian Zhou¹

• ¹Laboratory of Sports and Health Promotion, School of Physical Education, Sichuan University of Arts and Science, Dazhou, 635000; China, DaZhou, China
• ²School of Physical Education, China West Normal University, Nanchong, Shanxi Province, China

Objective: Previous investigations have demonstrated that engaging in physical activity is a vital behavioral element in mitigating experiences of depression, anxiety, and stress. However, the specific mechanisms by which dietary practices and physical activity interact to affect these psychological conditions are not fully understood. Thus, this study aimed to comprehensively examine the relationships among physical activity, diet, and mental health outcomes, specifically depression, anxiety, and stress, among college students and to elucidate the pathways through which these factors interact. Method: This study analyzed 1076 college students (18.8 ± 0.8 years old) via the Adult Dietary Behavior Questionnaire (covering eight dimensions), the Physical Activity Scale, and the Depression-Anxiety-Stress Scale. Results: There were significant differences in dietary behavior and physical activity parameters between male and female college students, but no significant differences were observed in depression, anxiety, or stress. The dimensions of college students' diet were significantly correlated with anxiety, stress, and depression (p < 0.01). Higher levels of physical activity were negatively correlated with anxiety, stress, and depression symptoms in college-aged students (p < 0.01). Dietary behavior was significantly correlated with college students' physical activity. Through structural equation modeling analysis, our findings revealed that physical activity not only directly reduced depression, stress and anxiety among college students but also indirectly alleviated them by improving their dietary behaviors. The direct effects of physical activity on depression, anxiety and stress in college students were greater than the mediating effects of dietary behavior. Conclusion: Regular physical activity is key to reducing depression, anxiety, and stress in college students, with dietary behavior mediating this effect; thus, promoting exercise and 2 / 30 healthy eating in universities is recommended for better mental health. Future research should explore this relationship across different populations for valuable insights into mental health interventions.