Health literacy is widely regarded as an important empowerment tool with the potential to reduce health inequalities. This is because the groups most at risk of limited health literacy are also known to have the poorest health outcomes. For many vulnerable or disadvantaged people, a lack of financial and social resources – such as education, good quality work or strong social connections – as well as stress linked to ill health and limited resources, can reduce opportunities to develop the capabilities needed to be actively involved in decisions about health and the conditions that affect health (critical and interactive health literacy