PurposeThe purpose of this research is to develop a dynamic conceptual framework depicting factors related to the adoption of a healthy diet, which will underpin the development of an agent-based model (ABM) to uncover the dynamic interplay between these factors.Design/methodology/approachThe conceptual framework was developed in three steps using available empirical data from a semi-structured in-depth interview qualitative study, comprehensive systematic literature searches, existing theories and models and expert opinions from across the world.FindingsThe conceptual framework explicitly presents intention as the key determinant of the tendency to adopt a healthy diet. Intention is determined by demographic, psychological and behavioural factors and individual dietary mindset factors and dynamically affected by social environment and the person's past behaviour. The relationship between intention and behaviour is dynamically moderated by perceived control factors (price and accessibility of healthy food and time).Originality/valueThe conceptual framework developed in this study is well supported by evidence and experts' opinions. This conceptual framework will be used to design the ABM of this study, and it can be used in future investigations on the tendency to adopt healthy diet and food choices.