Associations between diet, exercise, and mental health among college students in Guangdong, China: A cross-sectional and interventional study.

College students reported substantial stress and anxiety and exhibited depressive symptoms, with mean scores nearing and/or crossing mild thresholds.

• Data collected from a sample of N=683 college students using the Depression Anxiety Stress Scale-21 (DASS-21)
• Students reported substantial stress and anxiety alongside depressive symptoms
• Mean scores on stress, anxiety, and depression subscales neared and/or crossed mild threshold levels
• Cross-sectional study conducted in Guangdong, China

Dietary quality showed suboptimal physical and psychosocial correlates, with positive associations with cereals, condiments, and energy-dense foods, and negative associations with vegetables, fruits, dairy, and protein.

• Dietary quality assessed using the Diet Balance Index-16 (DBI-16)
• Positive associations found between dietary quality scores and cereals, condiments, and energy-dense foods
• Negative associations found between dietary quality scores and vegetables, fruits, dairy, and protein intake
• These patterns indicate dietary imbalances characterized by excess of certain food groups and deficiency of nutritionally dense foods

A majority of participants reported a low level of physical activity, with notable differences across genders and grade levels.

• Physical activity assessed using the Physical Activity Rating Scale-3 (PARS-3)
• A majority of the 683 cross-sectional participants were classified as having low physical activity levels
• Significant differences in physical activity levels were observed across genders
• Significant differences in physical activity levels were also observed across grade levels

Increases in physical activity were correlated with improved mental health, while more severe dietary imbalances were associated with worsened mental health.

• Correlation analyses were conducted among physical activity, dietary quality, and mental health measures
• Higher physical activity levels were positively associated with better mental health outcomes
• Greater dietary imbalance was associated with worse mental health outcomes including stress, anxiety, and depression
• Statistical methods employed included nonparametric group comparisons and correlation analyses

Participants in the control group exhibited greater improvements in stress, anxiety, depression, physical activity, and dietary balance compared to the intervention group.

• Intervention trial included 440 participants: 220 intervention participants and 220 control participants
• The control group showed greater improvements than the intervention group across all measured outcomes: stress, anxiety, depression, physical activity, and dietary balance
• All between-group differences reached statistical significance (all P < .05)
• Pre-post comparisons were used to assess changes within and between groups