The 2019 Nutrition Society Spring Conference, which convened in Dundee, focused on the challenges presented by inter-individual differences in the responses to nutrition and in conducting nutritional research. The programme brought together national and international experts to discuss the collective evidence on inter-individual nutritional responses and impacts on health. Speakers and delegates from across the UK, Europe and the USA debated new methods of conducting research in nutrition and discussed the development of appropriate dietary interventions to maintain health and prevent disease in diverse populations. Symposium 1 focused on the effects of ethnicity on nutrient availability and type 2 diabetes and cardio-metabolic disease. Symposium 2 explored sex differences in nutrient availability and health and metabolism. The final symposium examined genetic and phenotypic variation, nutrition and health. The meeting ended with a panel discussion about how we take research to recommendations and concluded with a need to consider inter-individual differences in planning, conducting and analysing nutritional research.