Limitations of current analytical reference methods to determine vitamins in foods: Challenges to support regulatory compliance and nutritional composition data

Foods are analysed for their vitamin content to support the verification of regulatory compliance or to generate food composition data. Many international reference methods for the analysis of vitamins in foods originate from the 1990s. Advances in nutrition science and analytical technology and the continuing evolution of statutory regulations necessitate the need of new or supplementary regulatory standards. We have evaluated recent developments in these areas and conclude that most current international reference methods are no longer fit-for-purpose to accurately determine vitamin content in foods and food supplements. We have made recommendations to consider new and/or updated reference methods and regulatory standards for the analysis of vitamins A, D, E, K, B₁, B₂, B_3, B₅, B₆, B₇, B₉, B₁₂, C and carotenoids in foods and food supplements. This area of nutrients may benefit from globally harmonised definitions specifying what compounds to include or exclude for analysis, and applicable bioactivity factors.