Self-Management Behaviours and Health Literacy in Adults with Type 2 Diabetes Mellitus: A Scoping Review.

Background: Self-management of diabetes is significantly affected by health literacy; however, its role in affecting specific behaviours is not well understood. This scoping review synthesised the existing evidence on the mechanisms, mediators, and contextual factors through which health literacy influences self-management behaviours among adults with Type 2 Diabetes Mellitus (T2DM). Methods: The scoping review was conducted in accordance with the Joanna Briggs Institute (JBI) methodological framework and reported following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews (PRISMA-ScR). A systematic search was conducted in PubMed/MEDLINE, Scopus, Web of Science, and Google Scholar from inception to July 2026. Studies were eligible if they examined health literacy and diabetes self-management among adults with T2DM in any healthcare or community setting worldwide. Following screening, twenty-four studies were included. Data were charted and synthesised into themes based on Bandura's Social Cognitive Theory. Results: Findings were organised into two themes. Theme 1 identified cognitive, behavioural, psychological, and interpersonal mechanisms—including diabetes knowledge, self-efficacy, social support, and digital health literacy—through which health literacy influences self-management. Theme 2 identified individual, social, cultural, and healthcare-system factors—including age, gender, education, socioeconomic status, culture, and digital competence—that mediate or moderate this relationship. Self-efficacy was the most frequently reported mediator; however, health literacy alone was insufficient to improve outcomes, and digital interventions were effective only when patients possessed adequate digital literacy. Conclusion: The association among diabetes outcomes, self-management and health literacy is multifaceted. It calls for multifaceted, culturally responsive and digitally inclusive interventions that simultaneously build health literacy and self-efficacy to improve sustainable self-management of adults with T2DM. Longitudinal and intervention studies are needed to establish causal relationships.