Eat your way to better mood? diet trial targets depression

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: 1. Hong Kong residents aged 18-65 years; 2. Able to read Chinese and type in Chinese or English; 3. Have a Patient Health Questionnaire-9 (PHQ-9) score of 10 or higher, indicating at least a moderate level of depressive symptoms; 4. Meet the Diagnostic and Statistical Manual of Mental Disorders (DSM) diagnostic criteria for current MDD according to the Mini International Neuropsychiatric Interview (MINI); 5. Have a Mediterranean Diet Index (KIDMED 2.0) score less than 3, indicating very-low-quality diet; 6. Possess an Internet-enabled iOS- or Android-operated mobile device; and 7. Willing to provide informed consent and comply with the trial protocol. Exclusion Criteria: 1. The presence of other current psychiatric disorders as assessed by the MINI (bipolar disorder, posttraumatic stress disorder, personality disorders, eating disorders, psychotic disorders, or substance abuse disorder); 2. Have a medical condition or neurocognitive disorder that may prevent dietary changes as recommended by physicians or dietitians; 3. Current serious suicidal risk (non-fleeting intent or plan) as assessed by a PHQ-9 Item 9 score \>2 (referral information to professional mental health services will be provided); 4. Involvement in dietary changes (self-initiated/supervised by professionals) in the past 2 weeks; 5. Involvement in any psychological treatment specifically for depression in the past 6 months; 6. A change in medication within 2 weeks prior to the baseline assessment/during the study; 7. Pregnancy and hospitalization; 8. Current participation in any other trial(s); and 9. Unwilling to change their diet if being allocated to the MediDiet group or food allergies or intolerances preventing diet adherence (specifically allergies to seafood, soy, nuts, yogurt, or dairy products).