Reducing meat consumption and following plant-based diets: Current evidence and future directions to inform integrated transitions

Background: There is increasing consensus that transitioning towards reduced meat consumption and more plant-based diets is a key feature to address important health and sustainability challenges. However, relevant evidence that may inform these transitions remains fragmented with no overarching rationale or theoretical framework, which limits the ability to design and deliver coordinated efforts to address these challenges. Scope and approach: Eleven databases were systematically searched using sets of keywords referring meat curtailment, meat substitution and plant-based diets, as well as consumer choice, appraisal or behavior (2602 articles selected for title and abstract screening; 161 full-texts assessed for eligibility; 110 articles selected for extraction and coding). Barriers and enablers were identified and integrated into an overarching framework (i.e., COM-B system), which conceptualizes behavior as being influenced by three broad components: capability, opportunity and motivation. Key findings and conclusions: This review mapped potential barriers and enablers in terms of capability, opportunity, and motivation to reduce meat consumption and follow more plant-based diets. These included lack of information for consumers and difficulty to acquire new cooking skills (barrier, capability), changes in service provision in collective meal contexts (enabler, opportunity), and positive taste expectations for plant-based meals (enabler, motivation). Evidence on variables referring to the motivation domain is clearly increasing, but there is a striking need for studies that include capability and opportunity variables as well. The results of this review are relevant to a variety of fields and audiences interested in promoting sustainable living and health improvements through dietary choice.