Understanding of the role of dietary fats and fatty acids in human health is constantly evolving. Our department has a longstanding interest in the effects of manipulating dietary fat composition on cardiometabolic disease risk factors. Our investigations have included the postprandial effects of algal and fish sources of long chain omega-3 fatty acid and characterising PUFA-derived lipid mediator profiles in vegans and omnivores. Many of our studies have explored the role of saturated fatty acids and differences in fat structure on postprandial changes in metabolism and vascular function. Another research focus is on the role of omega-3 fatty acids in brain development and mental health. Ongoing work is determining the effects of omega-3 fatty acid deficiency and supplementation on neurodevelopmental outcomes in rat models, and associations of omega-3 fatty acid intake and status with paediatric and perinatal depression in human observational studies.