Empowering the Citizen in the Main Pillars of Health by Using IoT Meritxell G´ omez-Mart´ ınez, Silvia Orte, Laura Ros-Freixedes, Kian Seif, and Eloisa Vargiu (B ) Eurecat, Centre Tecn`ologic, eHealth Unit, Barcelona, Spain {meritxell.gomez-martinez,silvia.orte, laura.ros-freixedes,kian.seif,eloisa.vargiu}@eurecat.org Abstract. To live longer, healthier, and more active, people at any age have to follow simple and clear suggestions that cover the 3 main pillars of health: physical activity, nutrition, and sleeping. Unfortunately, due to the intrinsic (e.g., daily-life habits) and extrinsic (e.g., environmental change) factors, people are far to have a healthy life and, thus, there is an increase of chronic diseases, mental disorders, and premature death. Approaches to increase citizen empowerment vary from self-management programs to those for promoting citizen (especially patients) involvement in treatment shared decision-making, to those to facilitating also the clinician-patient cooperation, when required. This paper presents the approach followed in CarpeDiem, an IoT-based system focused on self- management as a way to engage and empower citizens in order to improve their quality of life, to allow a better follow-up by clinicians in case of patients or elderly people, and to improve training in case of sportsmen. Keywords: Healthy habits · Citizen empowerment · Physical activity · Nutrition · Sleeping activity · Activity monitoring · Recommender system 1 Introduction Digital tools represent a valuable potential resource for healthcare systems, especially when addressing populations with a high prevalence of risk factor clustering. However, although technological innovations may provide monitoring instruments which can improve person-centred care, they are often ineffective or underutilised due to barriers associated with implementation. These include issues such as the incompatibility of the technology to the local context, limited interoperability, poor system performance, increased cost, lack of financial incen- tives, inadequacy of legislation and policies, poor organisation of work, health M.G´omez-Mart´ ınez, S. Orte, L. Ros-Freixedes, K. Seif—Contributed equally to the work. c  ICST Institute for Computer Sciences, Social Informatics and Telecommunications Engineering 2021 Published by Springer Nature Switzerland AG 2021. All Rights Reserved P. Perego et al. (Eds.): ICWH 2020, LNICST 376, pp. 37–53, 2021. https://doi.org/10.1007/978-3-030-76066-3_4