Contextual adaptation and multi-level factors influence translation of dietary interventions for type 2 diabetesBarriers and helpers for managing type 2 diabetes diets

IntroductionDietary intervention is the core of type 2 diabetes mellitus (T2DM) management, yet substantial gaps exist between evidence-based dietary guidelines and real-world implementation in resource-limited settings including low- and middle-income countries (LMICs) and marginalized subgroups within high-income nations. Implementation science frameworks such as the updated Consolidated Framework for Implementation Research (CFIR 2.0) enable systematic analysis of multi-level barriers and facilitators of dietary strategies, but comprehensive cross-regional synthesis targeting resource-scarce populations remains scarce. This scoping review aims to map, categorize, and interpret factors shaping the translation of evidence-based T2DM dietary interventions across resource-limited contexts using the CFIR 2.0 framework.MethodsThis scoping review strictly followed PRISMA-ScR reporting standards. We systematically searched PubMed, Web of Science, CNKI and other Chinese/English databases from database inception to March 1, 2026 for quantitative, qualitative and mixed-method studies focused on the implementation, barriers, enablers or cultural adaptation of T2 dietary interventions in resource-limited populations. Two independent reviewers completed study screening, full-text eligibility assessment and CFIR deductive thematic coding; disagreements were resolved via group discussion. Co-occurrence network analysis visualized interconnections between implementation themes, and stratified comparative synthesis was performed to distinguish disparities between LMICs and disadvantaged subgroups in high-income countries.ResultsA total of 643 initial records were retrieved, and 113 eligible studies covering Asia, Africa, North America and other regions were finally included. Five core CFIR domains jointly determine implementation outcomes, with localized cultural adaptation serving as the overarching central theme: 1. Individual characteristics: Knowledge and skill deficits (85/113 studies) and biased health attitudes were dominant barriers; peer education and targeted belief reshaping acted as key facilitators. 2. Outer setting: Food deserts, mismatched sociocultural eating norms and insufficient public health policy investment hindered adherence, while community organizations, religious stakeholder collaboration and revitalized traditional food culture boosted intervention uptake. 3. Inner setting: Shortages of nutrition professionals and incomplete primary care structural systems formed institutional barriers; standardized diabetes clinics and multi-disciplinary cooperation delivered organizational support. 4. Intervention characteristics: Generic one-size-fits-all dietary tools lacked contextual adaptability, while low-carb protocols and stage-matched personalized nutrition plans possessed robust clinical evidence and high implementability after local co-design. 5. Implementation process: Lack of standardized training for frontline staff was a major barrier; layered offline group courses, low-tech paper tracking tools and voice-based mobile reminders facilitated long-term execution. Notable disparities existed across two resource-limited population groups: LMIC implementation obstacles mainly stemmed from nationwide systemic underinvestment, whereas marginalized ethnic subgroups in high-income countries faced barriers rooted in colonial erosion of traditional food systems and racial health inequities. Co-occurrence network analysis confirmed knowledge-skill gaps as the central bridging factor linking all five CFIR domains. Evidence gaps included insufficient long-term follow-up studies (only 12% of studies tracked participants over 2 years) and limited data from African and rural Asian primary care contexts.DiscussionSustained, effective translation of T2DM dietary interventions cannot rely on single-point improvements, but requires synergistic optimization across all five CFIR domains centered on localized cultural adaptation. LMICs and high-income vulnerable subgroups demand differentiated intervention strategies due to divergent structural root causes. Four actionable multi-level recommendations are proposed: strengthening national chronic disease policy and grassroots nutrition resource investment; systematic nutrition capacity training for primary care providers; developing context-customized, simplified visual dietary tools; and building integrated hospital-community-family long-term follow-up support systems. Limitations of this review include exclusive Chinese-English literature retrieval and absence of formal bias risk evaluation. Future research should conduct hybrid implementation-effect trials, develop scalable CFIR+RE-AIM combined toolkits and carry out long-term multi-center studies in understudied African and rural Asian regions.Systematic review registrationhttps://osf.io/j2zh9/.