Health literacy is a critical determinant of health, which can empower individuals and lead to engagement in collective health promotion action and is also a crucial component in the self-management of illness. The current study moves beyond a focus on functional health literacy and presents findings from a longitudinal qualitative (LQ) study consisting of three phases. This paper presents findings from the second phase of the study, which assessed the development of health literacy capacities of individuals attending a structured cardiovascular risk reduction programme in Ireland. The study objectives were to: explore perceptions of changes in interactions and information exchange within health consultations; identify the facilitators associated with changes in health literacy capacities; assess developments in engagement with broader contexts for health literacy capacities. A LQ study design was undertaken, which employed repeat interview methodology with 19 participants (aged 36–76 years) 12 weeks after beginning a structured cardiovascular risk reduction programme. Health literacy levels were assessed using the HLS-EU 47 item instrument in phase 1 (68% limited health literacy (HL), 32% adequate health literacy). A semi-structured interview guide, (informed by Sørensen’s conceptual model of health literacy), was used to explore the development of health literacy and to identify changes in knowledge, attitudes and experiences over time. Thematic analysis was used, informed by aspects of Saldaña’s framework for longitudinal qualitative data analysis. All participants reported having acquired increased understanding of issues relevant to their health and self-care. Participants described health literacy capacities that incorporate aspects of all levels of health literacy (functional, interactive and critical). Core themes were identified corresponding to changes in these levels: re-engagement with health information and increased understanding of risk and protective factors (changes in functional health literacy); changes in interactions with healthcare providers (HCP) (changes in interactive health literacy); enhanced psychological insights and understanding the broader determinants of health (changes in critical health literacy). Findings support the development of health literacy capacities across the functional, interactive and critical health literacy domains. Participants are capable of locating responsibility for health beyond the individual level and are making sense of knowledge within their own social contexts. Individuals, regardless of their initial health literacy levels, are capable of engaging with broader issues that can impact on their health and can be supported to develop these critical health literacy capacities.