From harmful nutrients to ultra-processed foods: exploring shifts in ‘foods to limit’ terminology used in national food-based dietary guidelines

Abstract Objective: The choice of terms used to describe ‘foods to limit’ (FTL) in food-based dietary guidelines (FBDG) can impact public understanding, policy translation and research applicability. The choice of terms in FBDG has been influenced by available science, values, beliefs and historical events. This study aimed to analyse the terms used and definitions given to FTL in FBDG around the world, including changes over time and regional differences. Design: A review of terms used to describe FTL and their definitions in all current and past FBDG for adults was conducted, using a search strategy informed by the FAO FBDG website. Data from 148 guidelines (96 countries) were extracted into a pre-defined table and terms were organised by the categories ‘nutrient-based’, ‘food examples’ or ‘processing-related’. Setting: National FBDG from all world regions. Participants: None. Results: Nutrient-based terms (e.g. high-fat foods) were the most frequently used type of term in both current and past dietary guidelines (91 %, 85 %, respectively). However, food examples (e.g. cakes) and processing-related terms (e.g. ultra-processed foods) have increased in use over the past 20 years and are now often used in conjunction with nutrient-based terms. Regional differences were only observed for processing-related terms. Conclusion: Diverse, and often poorly defined, terms are used to describe FTL in FBDG. Policymakers should ensure that FTL terms have clear definitions and can be integrated with other disciplines and understood by consumers. This may facilitate the inclusion of the most contemporary and potentially impactful terminology in nutrition research and policies.