Whole of Diet Approaches to Mood and Mental Health: Exploring Dietary Patterns and Depression Using an Integrated Approach

Objective: This research aimed to expand evidence in the emerging field of Nutritional Psychiatry by answering questions: What is the overall state of the evidence between dietary patterns and the risk of depression? (ii) Is there an association between diet quality and depressive symptoms in Australian women over time? and (iii) What are individuals’ experiences with food and mood?

Methods: The association between dietary patterns and depression is a diverse body of literature consisting of epidemiological studies and several RCTs. An umbrella review exploring the state of this evidence, a longitudinal analysis of Australian women’s diet quality and depressive symptoms and focus groups exploring food and mood in Australians were conducted to understand the perceived and determined effects of dietary patterns and depression.

Results: The mixed-methods approach implied a relationship between dietary patterns and depressive symptoms. After adjusting for covariates, a small, significant effect was found between (i) healthy dietary patterns/higher diet quality and decreased depressive symptoms, and (ii) unhealthy dietary patterns/lower diet quality and increased symptoms. The importance of psychosocial and cultural factors such as social connectedness, food security, dietary choices, intuitive eating practices and bio-individuality were observed.

Conclusions: The findings of this research add support to the growing field of Nutritional Psychiatry for the relationship between dietary patterns and depression. A novel finding was that despite consuming a diet that is protective of depressive symptoms, plant-based dietary followers have higher rates of depression than the general population. Future research is needed to explore this unique relationship.