Nutritional Psychiatry: The Present State of the Evidence

Nutritional Psychiatry (NP) represents an innovative field at the intersection of nutrition and mental health, offering new insights into the prevention and treatment of psychiatric disorders through dietary modifications and nutrient supplementation. Amidst a global escalation in mental health issues and the limitations of traditional psychiatric medications, NP emerges as a vital complementary approach, focusing on diet quality as a modifiable risk factor for mental disorders. This chapter provides a comprehensive overview of NP, elucidating its theoretical foundations, the biological mechanisms linking diet to mental health (including inflammation, oxidative stress, neuroplasticity, and the gut–brain axis), and the current evidence base for dietary impacts on major psychiatric disorders such as depression, anxiety, schizophrenia, bipolar disorder, and ADHD. The ultimate goal is to pave the way for more effective, holistic, and personalized mental health care that addresses the dietary as well as psychological needs of individuals, underscoring the critical role of nutrition in mental well-being.