The recent implementation of the General Data Protection Regulation (GDPR) establishes a set of formal requirements that reinforce personal data protection, namely, those concerning the collection, treatment, and dissemination of data on research participants. With the application of this new legal provision at the European level, new types of restrictions are emerging, whose nature and reach intensify the tension between demands for privacy and scientific freedom in research. In this article, we take as a reference an ongoing research taking place in Portugal, in the field of Sociology of Health, concerning the consumption of medicines by professionals exposed to high-performance pressure. Our main objective is to identify and analyse the implications of regulatory challenges faced in the research process and how the researchers managed and overcame them. We present a critical narrative that sheds light on the nature of the choices taken while also assessing the practical implications for the operationalisation of the research. We conclude by noting that, despite the benefits that may flow from the application of GDPR, the new requirements regarding the protection of personal data may override the ethical principles of scientific research and strengthen regulatory restrictions on conducting research. In the research concerned, the significant practical implications were indirect access to participants, a more time-consuming process in terms of participant adherence and a temporal discrepancy between the different stages of recruitment.