An Integrated Conceptual Framework for the Sustainable Adoption of the Mediterranean Diet: The Mediating Role of Plant-Based Foods

Sustainable dietary transitions are increasingly recognised as essential for addressing the interconnected challenges of public health, environmental degradation and food system sustainability. Although the Mediterranean Diet (MD) is widely acknowledged as a healthy and sustainable dietary model, adherence has progressively declined across diverse populations. This study develops an integrated conceptual framework to explain the sustainable adoption of the Mediterranean Diet, with particular emphasis on the conceptual mediating role of plant-based foods. A structured conceptual narrative review was conducted using interdisciplinary evidence from nutrition science, sustainability research, behavioural sciences and food policy. The proposed framework integrates individual capacities, socio-cultural contexts, structural environments and ecological awareness within a systems-oriented perspective. The findings suggest that dietary behaviour is shaped by dynamic and context-dependent interactions influenced by feedback mechanisms, life-course transitions and structural constraints. Within this framework, plant-based foods function as integrative leverage points linking health, environmental and cultural dimensions. The study highlights the limitations of individual-centred approaches and emphasises the importance of coordinated multi-level strategies to support sustainable dietary transitions. Overall, the framework provides a theoretically grounded basis for future research, policy development and integrated interventions aimed at promoting resilient and sustainable food systems.