Associations of Dietary Behaviors and Physical Activity with Anxiety and Depressive Symptoms among Chinese Adults Aged 18-60 Years: A Population-based Cross-sectional Study.

This population-based cross-sectional study aimed to examine the associations of unhealthy diet and insufficient physical activity (PA) with anxiety and depressive symptoms among Chinese adults aged 18-60 years. Data were derived from the 2022-2023 Psychology and Behavior Investigation of Chinese Residents (PBICR) Project, a large cross-sectional survey conducted in China. After exclusions, 14,358 adults were included in this study. Dietary risk factors were summed into a 0-5 score. PA was measured by the International Physical Activity Questionnaire (IPAQ-7, short form). Anxiety and depressive symptoms were defined as the Generalized Anxiety Disorder Scale (GAD-7) ≥ 10 and Patient Health Questionnaire-9 (PHQ-9) ≥ 10, respectively. Adjusted odds ratios (a ORs) and 95% confidence intervals ( CIs) were estimated using ordered logistic regression; dose-response was examined with restricted cubic splines. Overall, 1,879 participants (13.09%) self-reported anxiety and 3,084 (21.48%) self-reported depressive symptoms. A monotonic dose-response relationship was observed between the number of unhealthy dietary behaviors and both outcomes. Compared with participants reporting no unhealthy dietary behaviors, those reporting 1, 2, 3, 4, and 5 behaviors had progressively higher odds of anxiety ( aOR = 1.47, 2.03, 2.75, 4.59, and 8.37) and depression ( aOR = 1.53, 2.14, 2.84, 5.59, and 16.46). Physical activity level was not significantly associated with either anxiety or depressive symptoms after adjustment for covariates. The strong relationship between cumulative unhealthy dietary behaviors and mental health symptoms highlights the potential importance of dietary interventions for preventing anxiety and depression.