Mediterranean-style Dietary Pattern (MDP), Mood and Anxiety

Inclusion Criteria: * Male and female, aged 18 or above * Is willing and able to comply with all study procedures, including changes in diets * Has access to and able to use the internet/computer/tablet device * Mild to moderate level of anxiety and/or depression symptoms, assessed by Generalised Anxiety disorder (GAD-7) score and Patient Health Questionnaire (PHQ-9), scores 5 to 14 on both questionnaires * A habitual MEDAS score of ≤ 7/14 * To be fluent in English Exclusion Criteria: * MEDAS score \>7 * Vegan/vegetarian * Allergies to one of the study components i.e. nuts, fish * On antidepressant or antianxiety medication where dosage is likely to change over the next 3 month * Factors precluding MRI scanning such as suffers from claustrophobia or has metal implants * Not fluent in English * Not agreement for the study team to contact the participants general practitioner about trial participation and screening results * Not prepared to make changes to the diet for 10 days (2 x 5 day periods)