Dietary Inflammation and Mental Health

While the impact of diet on physical health outcomes is well established, the role of dietary and nutritional factors in the onset and outcomes of mental illness is yet to be fully understood. Nonetheless, there is an increasing evidence-base showing that poor diet is associated with adverse mental health outcomes, and that certain nutritional-based therapies may be beneficial in the treatment of mental illness. In this chapter, we firstly describe what is generally considered to constitute a healthy vs. unhealthy diet (and the role these have in physical health outcomes), before going on to discuss the epidemiological and experimental evidence around the impact of diet on mental illness. In particular, the chapter focuses on how ‘dietary inflammation’ could explain the link between adverse diets and poor mental health, along with if and how dietary improvement and nutritional supplements could potentially be used to improve outcomes. Within this, the chapter also explores the emergent evidence around the role of the ‘gut microbiome’ in the link between diet, inflammation, and mental health. The chapter closes with a discussion on the overall implications of the existing evidence for addressing dietary factors in clinical practice.