Postbiotics: what are they?

Abstract Although several internationally recognised scientific groups and non-governmental organisations have attempted to define ‘postbiotics,’ there remains no consensus. Leading experts have highlighted persistent problems of terminological inconsistency, lack of standardisation, and unclear boundaries between related concepts. What is needed is a comprehensive analysis that integrates existing definitions with considerations of manufacturing processes, mechanisms of action, and clinical applications. Ultimately, progress requires harmonisation of terminology to ensure comparability across studies and to provide a solid foundation for both academic and industry development.