Allergy is one of the most common immune disorders in children, affecting up to 20% of children in industrialized countries. Dietary factors are thought to be a main factor contributing to the onset of allergies. Professor Maria Makrides focuses on long-chain polyunsaturated fatty acids (LCPUFAs). Why might these fatty acids be related to allergies? Makrides shows that the balance of n-3 versus n-6 LCPUFAs in the diet can cause biochemical changes that tip the immune system for or against inflammation. Can prenatal LCPUFA supplements alleviate the incidence of allergic disorders in childhood?Results from the DOMInO study showed some benefits, but these were not statistically significant. Makrides then describes a systematic review of 7 randomized controlled trials in nearly 2400 children. The findings from this review echo the DOMInO results, with heterogeneous data that suggest the benefits of LCPUFAs without showing statistical significance. Makrides concludes by outlining a series of points that need to be defined before we can begin to translate these findings into clinical practice.