Technical Guidelines for the Evaluation of Scientific Evidence of Health and Function Claims for Food and Food Ingredients: A Federation of Asian Nutrition Societies (FANS) Consensus

Background: Health and function claims are central to advancing nutrition science and regulatory practice, particularly across Asia, where the harmonization of nutrition labeling standards faces unique and complex challenges. Fragmented national regulatory frameworks, combined with the region’s diverse range of food ingredients and traditional herbal products, have created substantial inconsistencies in scientific evaluation practices and cross-border trade. Objective: To establish a harmonized, evidence-based technical framework for evaluating the scientific evidence underpinning health and function claims for foods and food ingredients. Methods: The Task Force on Health & Function Claims of the Federation of Asian Nutrition Societies (FANS) developed this guideline through a structured process of expert consultation, iterative peer review, and formal consensus building. The framework comprises six core components: (1) core principles; (2) standardized procedures for evidence evaluation; (3) criteria for assessing literature quality; (4) criteria for grading evidence strength; (5) requirements for evidence report preparation and (6) evidence-based recommendations. Results: This guideline defines standardized terminology for health and function claims, establishes core principles for evidence-based nutrition practice, specifies the requirement of qualified evaluator, details comprehensive and replicable literature evaluation procedures, and adopts a four-tiered evidence strength grading system (Grades A–D). It prescribes transparent, verifiable pathways for claim substantiation and periodic re-evaluation to uphold scientific rigor and ensure consumer protection. Conclusions: This guideline aligns with prevailing international standards while being specifically adapted to the Asian regional context. It provides a unified technical framework for the evaluation of health and function claims in Asia. It is designed to facilitate regulatory convergence across the region, safeguard consumer interests, and foster responsible innovation in the functional food sector, while laying a robust foundation for collaborative regional nutritional research and regulatory alignment.