Under the theoretical assumptions of individual bounded rationality and of behavioural psychology about human actions and agency, nudge has been promoted as an alternative to traditional regulatory tools, characterized by being inexpensive, choice-preserving, and bound to promote legitimate goals and citizens' welfare within through specific choice architectures. Applicable to several domains, health included, the nudging approach runs in connection with requests and needs arising from marketing strategies, with the aim of maximizing economic rationality and efficiency. However, as nudge was framed having in mind the notion of consumer, it fails to fully meet the values connected to the idea of citizenship. Most nudges strategies seem to imply a top-down vision - though soft paternalistic - where pre-defined and often black-boxed values pretend to define individual and collective directions. The representational and ethical issues surrounding nudge, the psychological mechanisms working behind it, and the correlated legal issues request a precise and accurate scrutiny, if we want nudging interventions to be legitimately and democratically framed within policy strategies and human agency not to be disregarded, but empowered by behaviourally-based actions.