Professor REVEALS How Your Diet Can Reduce STRESS & ANXIETY! | Felice Jacka

She describes a long-standing split in medicine between “mind” and “body,” and says newer evidence on immune function, brain plasticity, and the gut microbiota supports viewing mental health as tightly connected to physical systems influenced by diet.

She says large studies show poor diet is a major global driver of poor health outcomes, while mental and substance use disorders are a leading cause of disability; she argues the link between diet and mental health matters for both prevention and treatment.

She explains that observational (epidemiological) studies can show associations, but intervention trials are needed to test causality, while also noting nutrition trials are difficult because you can’t realistically blind diets or ethically assign “junk food” diets.

She describes the SMILES trial: people with major depressive disorder were randomized to social support or dietary support from a clinical dietitian for three months, with the diet group showing much higher remission than the social support group.

She highlights findings that participants could make meaningful dietary changes, that greater dietary change tracked with greater mood improvement, and that the recommended diet cost less than participants’ baseline diets; she also notes a similar trial in South Australia found comparable results and high cost-effectiveness.