In order to study human society, social scientists draw upon a variety of information, including measurements of societal or individual phenomena – data. It is an enduring challenge to capture appropriate data to help understand complex societal issues. Many researchers are, therefore, keen to explore the potential of new sources of data. Collection of data – your data, our data – has become ever-present in today’s digitally connected landscape, so it is important to balance the potential benefit to our understanding against legitimate concerns regarding data use. ‘Big Data’ has been both heralded as a panacea and demonised as unethical. This talk presents part of a collaborative project, the ESRC Strategic Network for Obesity, in which we summarised ways that new forms of data had been used creatively in academic obesity literature. Data from sources as varied as transport cameras to fitness trackers, from retail sales to social media, have already been used to investigate diet or physical activity. These data offered unique opportunities in scope, population access, objectivity and immediacy. At the same time, there are critical questions regarding the appropriateness of ‘repurposing’ data for obesity research: issues of data access and ownership, data quality and representativeness of the population.