Diet as a therapeutic target in depression: A randomised controlled trial

INTERVENTION: After a screening visit, participants will be randomly allocated to either a dietary intervention group or a social support control condition. The intervention will consist of 3 weekly educational and counselling sessions, targeting diet, followed by 4 two‐weekly booster sessions. In each of the sessions, background information as well as strategies to address dietary change and adherence will be presented. At the commencement, each participant will be provided with a sample meal plan and selected ingredients: oil, margarine and, nuts (e.g. walnuts as high in n‐3 PUFA) for snacks (over the duration of the study). Examples of portions of fish and lean cuts of meat will also be provided. Sessions will be one on one, face to face and approximately 1 hour in length. CONDITION: Major Depression PRIMARY OUTCOME: The primary outcome measures will be change in symptoms of ; depression, measured by the Montgomery‐Asberg Depression Rating Scale (MADRS) SECONDARY OUTCOME: Alcohol (Food Frequency Questionnaire) Anxiety‐ Hospital Anxiety and Depression Scale (HADS) ; samples Blood glucose (fasting blood samples) Blood pressure‐ Sphygmomanometer C‐Reactive protein (venous fasting sample‐fasting) Cost efficacy (Assessment of Quality of Life (AQoL 8D) Depression severity ‐ Clinical Global Impression Scales (CGI) (Severity and Improvement) Diet (Food Frequency Questionnaire, Dietary Screening Tool and food diary) Haemoglobin A1C (fasting blood samples) High Density Lipoproteins (HDL), Low Density Lipoproteins (LDL), Cholesterol (venous fasting blood samples) IL‐6 (Interleukin 6) (Venous blood sample‐fasting) Medication for blood pressure (self report) Physical Activity (Active Australia) Plasma fatty acids and carotenoids (fasting blood samples) Quality of Life‐ Short Form (SF 36), the WHO well‐being index, Assessment of Quality of Life (AQoL 8D) Smoking (Food Frequency Questionnaire) TNF alpha (Venous blood sample‐fasting) triglycerides (fasting blood samples) Weight and waist INCLUSION CRITERIA: Aged 18 or over; have the capacity to consent to the study and to follow its instructions and procedures; fulfil the DSM‐IV‐TR diagnostic criteria for Major Depressive Disorder, Single Episode or Recurrent, as well as scoring 18 or over on the MADRS at the time of entry into the study. Antidepressant therapy is not an inclusion criterion; however, those on antidepressant therapy need to have been on the same treatment for at least two weeks prior to randomisation. Habitual diet quality will be assessed at screening using the validated Dietary Screening Tool (DST), and only those below the predetermined cutoff (less than 60= categorized as “at risk”) will be eligible for the study