Mass media plays a central role in the continually changing public discourse on health and illness. In order to examine how shared knowledge is produced and transformed in mass media the ways mental health related issues were represented in the two major Swedish daily newspapers in 2009 were subjected to a qualitative analysis. Drawing on the theory of social representations the analysis focuses on how different perspectives are applied in the articles and how issues concerning mental health are represented. The results show that this discourse can be characterized as a dialogue with salient argumentative features: the perspectives of lay persons are supplemented by views of medical experts and others in what constitutes a field of contestation (Crossley 2006) where a number of conflicts are made explicit and central issues concerning both the nature of mental health/illness and authoritative knowledge are addressed. Representations of mental health and illness are characterised in terms of a tension between 'othering' and 'normalizing' representations. A tension between confidence/dependence and contestation/distrust is likewise found to characterise representations of expert knowledge. The results indicate an ambivalence regarding the authoritative role of expert knowledge concerning mental health as critique and expressions of distrust are juxtaposed with signs of confidence and dependence on professionals. The implications of the study applies to the relations between lay persons and 'psy-professionals' (Rose 1999) and the expectations that are placed on expert knowledge in a wide range of societal issues and in peoples’ everyday life.